Intracellular Reverse Transcription of Pfizer BioNTech COVID-19 mRNA Vaccine BNT162b2 In Vitro in Human Liver Cell Line

Authors:  Markus Aldén 1,Francisko Olofsson Falla 1,Daowei Yang 1,Mohammad Barghouth 1,Cheng Luan 1,Magnus Rasmussen 2 andYang De Marinis 1,*1Department of Clinical Sciences, Lund University, 20502 Malmö, Sweden2Infection Medicine, Department of Clinical Sciences, Lund University, 22362 Lund, Sweden

Abstract

Preclinical studies of COVID-19 mRNA vaccine BNT162b2, developed by Pfizer and BioNTech, showed reversible hepatic effects in animals that received the BNT162b2 injection. Furthermore, a recent study showed that SARS-CoV-2 RNA can be reverse-transcribed and integrated into the genome of human cells. In this study, we investigated the effect of BNT162b2 on the human liver cell line Huh7 in vitro. Huh7 cells were exposed to BNT162b2, and quantitative PCR was performed on RNA extracted from the cells. We detected high levels of BNT162b2 in Huh7 cells and changes in gene expression of long interspersed nuclear element-1 (LINE-1), which is an endogenous reverse transcriptase. Immunohistochemistry using antibody binding to LINE-1 open reading frame-1 RNA-binding protein (ORFp1) on Huh7 cells treated with BNT162b2 indicated increased nucleus distribution of LINE-1. PCR on genomic DNA of Huh7 cells exposed to BNT162b2 amplified the DNA sequence unique to BNT162b2. Our results indicate a fast up-take of BNT162b2 into human liver cell line Huh7, leading to changes in LINE-1 expression and distribution. We also show that BNT162b2 mRNA is reverse transcribed intracellularly into DNA in as fast as 6 h upon BNT162b2 exposure.

1. Introduction

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was announced by the World Health Organization (WHO) as a global pandemic on 11 March 2020, and it emerged as a devasting health crisis. As of February 2022, COVID-19 has led to over 430 million reported infection cases and 5.9 million deaths worldwide [1]. Effective and safe vaccines are urgently needed to reduce the morbidity and mortality rates associated with COVID-19.Several vaccines for COVID-19 have been developed, with particular focus on mRNA vaccines (by Pfizer-BioNTech and Moderna), replication-defective recombinant adenoviral vector vaccines (by Janssen-Johnson and Johnson, Astra-Zeneca, Sputnik-V, and CanSino), and inactivated vaccines (by Sinopharm, Bharat Biotech and Sinovac). The mRNA vaccine has the advantages of being flexible and efficient in immunogen design and manufacturing, and currently, numerous vaccine candidates are in various stages of development and application. Specifically, COVID-19 mRNA vaccine BNT162b2 developed by Pfizer and BioNTech has been evaluated in successful clinical trials [2,3,4] and administered in national COVID-19 vaccination campaigns in different regions around the world [5,6,7,8].BNT162b2 is a lipid nanoparticle (LNP)–encapsulated, nucleoside-modified RNA vaccine (modRNA) and encodes the full-length of SARS-CoV-2 spike (S) protein, modified by two proline mutations to ensure antigenically optimal pre-fusion conformation, which mimics the intact virus to elicit virus-neutralizing antibodies [3]. Consistent with randomized clinical trials, BNT162b2 showed high efficiency in a wide range of COVID-19-related outcomes in a real-world setting [5]. Nevertheless, many challenges remain, including monitoring for long-term safety and efficacy of the vaccine. This warrants further evaluation and investigations. The safety profile of BNT162b2 is currently only available from short-term clinical studies. Less common adverse effects of BNT162b2 have been reported, including pericarditis, arrhythmia, deep-vein thrombosis, pulmonary embolism, myocardial infarction, intracranial hemorrhage, and thrombocytopenia [4,9,10,11,12,13,14,15,16,17,18,19,20]. There are also studies that report adverse effects observed in other types of vaccines [21,22,23,24]. To better understand mechanisms underlying vaccine-related adverse effects, clinical investigations as well as cellular and molecular analyses are needed.A recent study showed that SARS-CoV-2 RNAs can be reverse-transcribed and integrated into the genome of human cells [25]. This gives rise to the question of if this may also occur with BNT162b2, which encodes partial SARS-CoV-2 RNA. In pharmacokinetics data provided by Pfizer to European Medicines Agency (EMA), BNT162b2 biodistribution was studied in mice and rats by intra-muscular injection with radiolabeled LNP and luciferase modRNA. Radioactivity was detected in most tissues from the first time point (0.25 h), and results showed that the injection site and the liver were the major sites of distribution, with maximum concentrations observed at 8–48 h post-dose [26]. Furthermore, in animals that received the BNT162b2 injection, reversible hepatic effects were observed, including enlarged liver, vacuolation, increased gamma glutamyl transferase (γGT) levels, and increased levels of aspartate transaminase (AST) and alkaline phosphatase (ALP) [26]. Transient hepatic effects induced by LNP delivery systems have been reported previously [27,28,29,30], nevertheless, it has also been shown that the empty LNP without modRNA alone does not introduce any significant liver injury [27]. Therefore, in this study, we aim to examine the effect of BNT162b2 on a human liver cell line in vitro and investigate if BNT162b2 can be reverse transcribed into DNA through endogenous mechanisms.

2. Materials and Methods

2.1. Cell Culture

Huh7 cells (JCRB Cell Bank, Osaka, Japan) were cultured in 37 °C at 5% CO2 with DMEM medium (HyClone, HYCLSH30243.01) supplemented with 10% (v/v) fetal bovine serum (Sigma-Aldrich, F7524-500ML, Burlington, MA, USA) and 1% (v/v) Penicillin-Streptomycin (HyClone, SV30010, Logan, UT, USA). For BNT162b2 treatment, Huh7 cells were seeded with a density of 200,000 cells/well in 24-well plates. BNT162b2 mRNA vaccine (Pfizer BioNTech, New York, NY, USA) was diluted with sterile 0.9% sodium chloride injection, USP into a final concentration of 100 μg/mL as described in the manufacturer’s guideline [31]. BNT162b2 suspension was then added in cell culture media to reach final concentrations of 0.5, 1.0, or 2.0 μg/mL. Huh7 cells were incubated with or without BNT162b2 for 6, 24, and 48 h. Cells were washed thoroughly with PBS and harvested by trypsinization and stored in −80 °C until further use.

2.2. REAL-TIME RT-QPCR

RNA from the cells was extracted with RNeasy Plus Mini Kit (Qiagen, 74134, Hilden, Germany) following the manufacturer’s protocol. RT-PCR was performed using RevertAid First Strand cDNA Synthesis kit (Thermo Fisher Scientific, K1622, Waltham, MA, USA) following the manufacturers protocol. Real-time qPCR was performed using Maxima SYBR Green/ROX qPCR Master Mix (Thermo Fisher Scientific, K0222, Waltham, MA, USA) with primers for BNT162b2, LINE-1 and housekeeping genes ACTB and GAPDH (Table 1).Table 1. Primer sequences of RT-qPCR and PCR.

Table

2.3. Immunofluorescence Staining and Confocal Imaging

Huh7 cells were cultured in eight-chamber slides (LAB-TEK, 154534, Santa Cruz, CA, USA) with a density of 40,000 cells/well, with or without BNT162b2 (0.5, 1 or 2 µg/mL) for 6 h. Immunohistochemistry was performed using primary antibody anti-LINE-1 ORF1p mouse monoclonal antibody (Merck, 3574308, Kenilworth, NJ, USA), secondary antibody Cy3 Donkey anti-mouse (Jackson ImmunoResearch, West Grove, PA, USA), and Hoechst (Life technologies, 34850, Carlsbad, CA, USA), following the protocol from Thermo Fisher (Waltham, MA, USA). Two images per condition were taken using a Zeiss LSM 800 and a 63X oil immersion objective, and the staining intensity was quantified on the individual whole cell area and the nucleus area on 15 cells per image by ImageJ 1.53c. LINE-1 staining intensity for the cytosol was calculated by subtracting the intensity of the nucleus from that of the whole cell. All images of the cells were assigned a random number to prevent bias. To mark the nuclei (determined by the Hoechst staining) and the whole cells (determined by the borders of the LINE-1 fluorescence), the Freehand selection tool was used. These areas were then measured, and the mean intensity was used to compare the groups.

2.4. Genomic DNA Purification, PCR Amplification, Agarose Gel Purification, and Sanger Sequencing

Genomic DNA was extracted from cell pellets with PBND buffer (10 mM Tris-HCl pH 8.3, 50 mM KCl, 2.5 mM MgCl2, 0.45% NP-40, 0.45% Tween-20) according to protocol described previously [32]. To remove residual RNA from the DNA preparation, RNase (100 µg/mL, Qiagen, Hilden, Germany) was added to the DNA preparation and incubated at 37 °C for 3 h, followed by 5 min at 95 °C. PCR was then performed using primers targeting BNT162b2 (sequences are shown in Table 1), with the following program: 5 min at 95 °C, 35 cycles of 95 °C for 30 s, 58 °C for 30 s, and 72 °C for 1 min; finally, 72 °C for 5 min and 12 °C for 5 min. PCR products were run on 1.4% (w/v) agarose gel. Bands corresponding to the amplicons of the expected size (444 bps) were cut out and DNA was extracted using QIAquick PCR Purification Kit (Qiagen, 28104, Hilden, Germany), following the manufacturer’s instructions. The sequence of the DNA amplicon was verified by Sanger sequencing (Eurofins Genomics, Ebersberg, Germany).

Statistics

Statistical comparisons were performed using two-tailed Student’s t-test and ANOVA. Data are expressed as the mean ± SEM or ± SD. Differences with p < 0.05 are considered significant.

2.5. Ethical Statements

The Huh7 cell line was obtained from Japanese Collection of Research Bioresources (JCRB) Cell Bank.

3. Results

3.1. BNT162b2 Enters Human Liver Cell Line Huh7 Cells at High Efficiency

To determine if BNT162b2 enters human liver cells, we exposed human liver cell line Huh7 to BNT162b2. In a previous study on the uptake kinetics of LNP delivery in Huh7 cells, the maximum biological efficacy of LNP was observed between 4–7 h [33]. Therefore, in our study, Huh7 cells were cultured with or without increasing concentrations of BNT162b2 (0.5, 1.0 and 2.0 µg/mL) for 6, 24, and 48 h. RNA was extracted from cells and a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was performed using primers targeting the BNT162b2 sequence, as illustrated in Figure 1. The full sequence of BNT162b2 is publicly available [34] and contains a two-nucleotides cap; 5′- untranslated region (UTR) that incorporates the 5′ -UTR of a human α-globin gene; the full-length of SARS-CoV-2 S protein with two proline mutations; 3′-UTR that incorporates the human mitochondrial 12S rRNA (mtRNR1) segment and human AES/TLE5 gene segment with two C→U mutations; poly(A) tail. Detailed analysis of the S protein sequence in BNT162b2 revealed 124 sequences that are 100% identical to human genomic sequences and three sequences with only one nucleotide (nt) mismatch in 19–26 nts (Table S1, see Supplementary Materials). To detect BNT162b2 RNA level, we designed primers with forward primer located in SARS-CoV-2 S protein regions and reverse primer in 3′-UTR, which allows detection of PCR amplicon unique to BNT162b2 without unspecific binding of the primers to human genomic regions.

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Figure 1. PCR primer set used to detect mRNA level and reverse-transcription of BNT162b2. Illustration of BNT162b2 was adapted from previously described literature [34].RT-qPCR results showed that Huh7 cells treated with BNT162b2 had high levels of BNT162b2 mRNA relative to housekeeping genes at 6, 24, and 48 h (Figure 2, presented in logged 2−ΔΔCT due to exceptionally high levels). The three BNT162b2 concentrations led to similar intracellular BNT162b2 mRNA levels at the different time points, except that the significant difference between 1.0 and 2.0 µg/mL was observed at 48 h. BNT162b2 mRNA levels were significantly decreased at 24 h compared to 6 h, but increased again at 48 h.

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Figure 2. BNT162b2 mRNA levels in Huh7 cells treated with BNT162b2. Huh7 cells were treated without (Ctrl) or with 0.5 (V1), 1 (V2), and 2 µg/mL (V3) of BNT162b2 for 6 (green dots), 24 (orange dots), and 48 h (blue dots). RNA was purified and qPCR was performed using primers targeting BNT162b2. RNA levels of BNT162b2 are presented as logged 2−ΔΔCT values relative to house-keeping genes GAPDH and ACTB. Results are from five independent experiments (n = 5). Differences between respective groups were analyzed using two-tailed Student’s t-test. Data are expressed as the mean ± SEM. (* p < 0.05; ** p < 0.01; *** p < 0.001 vs. respective control at each time point, or as indicated).

3.2. Effect of BNT162b2 on Human Endogenous Reverse Transcriptase Long Interspersed Nuclear Element-1 (LINE-1)

Here we examined the effect of BNT162b2 on LINE-1 gene expression. RT-qPCR was performed on RNA purified from Huh7 cells treated with BNT162b2 (0, 0.5, 1.0, and 2.0 µg/mL) for 6, 24, and 48 h, using primers targeting LINE-1. Significantly increased LINE-1 expression compared to control was observed at 6 h by 2.0 µg/mL BNT162b2, while lower BNT162b2 concentrations decreased LINE-1 expression at all time points (Figure 3).

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Figure 3.LINE-1 mRNA levels in Huh7 cells treated with BNT162b2. Huh7 cells were treated without (Ctrl) or with 0.5 (V1), 1 (V2), and 2 µg/mL (V3) of BNT162b2 for 6 (green dots), 24 (red dots), and 48 h (blue dots). RNA was purified and qPCR was performed using primers targeting LINE-1. RNA levels of LINE-1 are presented as 2−ΔΔCT values relative to house-keeping genes GAPDH and ACTB. Results are from five independent experiments (n = 5). Differences between respective groups were analyzed using two-tailed Student’s t-test. Data are expressed as the mean ± SEM. (* p < 0.05; ** p < 0.01; *** p < 0.001 vs. respective control at each time point, or as indicated; † p < 0.05 vs. 6 h-Ctrl).Next, we studied the effect of BNT162b2 on LINE-1 protein level. The full-length LINE-1 consists of a 5′ untranslated region (UTR), two open reading frames (ORFs), ORF1 and ORF2, and a 3′UTR, of which ORF1 is an RNA binding protein with chaperone activity. The retrotransposition activity of LINE-1 has been demonstrated to involve ORF1 translocation to the nucleus [35]. Huh7 cells treated with or without BNT162b2 (0.5, 1.0 and 2.0 µg/mL) for 6 h were fixed and stained with antibodies binding to LINE-1 ORF1p, and DNA-specific probe Hoechst for visualization of cell nucleus (Figure 4a). Quantification of immunofluorescence staining intensity showed that BNT162b2 increased LINE-1 ORF1p protein levels in both the whole cell area and nucleus at all concentrations tested (Figure 4b–d).

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Figure 4. Immunohistochemistry of Huh7 cells treated with BNT162b2 on LINE-1 protein distribution. Huh7 cells were treated without (Ctrl) or with 0.5, 1, and 2 µg/mL of BNT162b2 for 6 h. Cells were fixed and stained with antibodies binding to LINE-1 ORF1p (red) and DNA-specific probe Hoechst for visualization of cell nucleus (blue). (a) Representative images of LINE-1 expression in Huh7 cells treated with or without BNT162b2. (bd) Quantification of LINE-1 protein in whole cell area (b), cytosol (c), and nucleus (d). All data were analyzed using One-Way ANOVA, and graphs were created using GraphPad Prism V 9.2. All data is presented as mean ± SD (** p < 0.01; *** p < 0.001; **** p < 0.0001 as indicated).

3.3. Detection of Reverse Transcribed BNT162b2 DNA in Huh7 Cells

A previous study has shown that entry of LINE-1 protein into the nucleus is associated with retrotransposition [35]. In the immunofluorescence staining experiment described above, increased levels of LINE-1 in the nucleus were observed already at the lowest concentration of BNT162b2 (0.5 µg/mL). To examine if BNT162b2 is reversely transcribed into DNA when LINE-1 is elevated, we purified genomic DNA from Huh7 cells treated with 0.5 µg/mL of BNT162b2 for 6, 24, and 48 h. Purified DNA was treated with RNase to remove RNA and subjected to PCR using primers targeting BNT162b2, as illustrated in Figure 1. Amplified DNA fragments were then visualized by electrophoresis and gel-purified (Figure 5). BNT162b2 DNA amplicons were detected in all three time points (6, 24, and 48 h). Sanger sequencing confirmed that the DNA amplicons were identical to the BNT162b2 sequence flanked by the primers (Table 2). To ensure that the DNA amplicons were derived from DNA but not BNT162b2 RNA, we also performed PCR on RNA purified from Huh7 cells treated with 0.5 µg/mL BNT162b2 for 6 h, with or without RNase treatment (Ctrl 5 and 6 in Figure 5), and no amplicon was detected in the RNA samples subjected to PCR.

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Figure 5. Detection of DNA amplicons of BNT162b2 in Huh7 cells treated with BNT162b2. Huh7 cells were treated without (Ctrl) or with 0.5 µg/mL of BNT162b2 for 6, 24, and 48 h. Genomic DNA was purified and digested with 100 µg/mL RNase. PCR was run on all samples with primers targeting BNT162b2, as shown in Figure 1 and Table 1. DNA amplicons (444 bps) were visualized on agarose gel. BNT: BNT162b2; L: DNA ladder; Ctrl1: cultured Huh7 cells; Ctrl2: Huh7 cells without BNT162b2 treatment collected at 6 h; Ctrl3: Huh7 cells without BNT162b2 treatment collected at 24 h; Ctrl4: Huh7 cells without BNT162b2 treatment collected at 48 h; Ctrl5: RNA from Huh7 cells treated with 0.5 µg/mL of BNT162b2 for 6 h; Ctrl6: RNA from Huh7 cells treated with 0.5 µg/mL of BNT162b2 for 6 h, digested with RNase.Table 2. Sanger sequencing result of the BNT162b2 amplicon.

Table

4. Discussion

In this study we present evidence that COVID-19 mRNA vaccine BNT162b2 is able to enter the human liver cell line Huh7 in vitro. BNT162b2 mRNA is reverse transcribed intracellularly into DNA as fast as 6 h after BNT162b2 exposure. A possible mechanism for reverse transcription is through endogenous reverse transcriptase LINE-1, and the nucleus protein distribution of LINE-1 is elevated by BNT162b2.Intracellular accumulation of LNP in hepatocytes has been demonstrated in vivo [36]. A preclinical study on BNT162b2 showed that BNT162b2 enters the human cell line HEK293T cells and leads to robust expression of BNT162b2 antigen [37]. Therefore, in this study, we first investigated the entry of BNT162b2 in the human liver cell line Huh7 cells. The choice of BNT162b2 concentrations used in this study warrants explanation. BNT162b2 is administered as a series of two doses three weeks apart, and each dose contains 30 µg of BNT162b2 in a volume of 0.3 mL, which makes the local concentration at the injection site at the highest 100 µg/mL [31]. A previous study on mRNA vaccines against H10N8 and H7N9 influenza viruses using a similar LNP delivery system showed that the mRNA vaccine can distribute rather nonspecifically to several organs such as liver, spleen, heart, kidney, lung, and brain, and the concentration in the liver is roughly 100 times lower than that of the intra-muscular injection site [38]. In the assessment report on BNT162b2 provided to EMA by Pfizer, the pharmacokinetic distribution studies in rats demonstrated that a relatively large proportion (up to 18%) of the total dose distributes to the liver [26]. We therefore chose to use 0.5, 1, and 2 μg/mL of vaccine in our experiments on the liver cells. However, the effect of a broader range of lower and higher concentrations of BNT162b2 should also be verified in future studies.In the current study, we employed a human liver cell line for in vitro investigation. It is worth investigating if the liver cells also present the vaccine-derived SARS-CoV-2 spike protein, which could potentially make the liver cells targets for previously primed spike protein reactive cytotoxic T cells. There has been case reports on individuals who developed autoimmune hepatitis [39] after BNT162b2 vaccination. To obtain better understanding of the potential effects of BNT162b2 on liver function, in vivo models are desired for future studies.In the BNT162b2 toxicity report, no genotoxicity nor carcinogenicity studies have been provided [26]. Our study shows that BNT162b2 can be reverse transcribed to DNA in liver cell line Huh7, and this may give rise to the concern if BNT162b2-derived DNA may be integrated into the host genome and affect the integrity of genomic DNA, which may potentially mediate genotoxic side effects. At this stage, we do not know if DNA reverse transcribed from BNT162b2 is integrated into the cell genome. Further studies are needed to demonstrate the effect of BNT162b2 on genomic integrity, including whole genome sequencing of cells exposed to BNT162b2, as well as tissues from human subjects who received BNT162b2 vaccination.Human autonomous retrotransposon LINE-1 is a cellular endogenous reverse transcriptase and the only remaining active transposon in humans, able to retrotranspose itself and other nonautonomous elements [40,41], and ~17% of the human genome are comprised of LINE-1 sequences [42]. The nonautonomous Alu elements, short, interspersed nucleotide elements (SINEs), variable-number-of-tandem-repeats (VNTR), as well as cellular mRNA-processed pseudogenes, are retrotransposed by the LINE-1 retrotransposition proteins working in trans [43,44]. A recent study showed that endogenous LINE-1 mediates reverse transcription and integration of SARS-CoV-2 sequences in the genomes of infected human cells [25]. Furthermore, expression of endogenous LINE-1 is often increased upon viral infection, including SARS-CoV-2 infection [45,46,47]. Previous studies showed that LINE-1 retrotransposition activity is regulated by RNA metabolism [48,49], DNA damage response [50], and autophagy [51]. Efficient retrotransposition of LINE-1 is often associated with cell cycle and nuclear envelope breakdown during mitosis [52,53], as well as exogenous retroviruses [54,55], which promotes entrance of LINE-1 into the nucleus. In our study, we observed increased LINE-1 ORF1p distribution as determined by immunohistochemistry in the nucleus by BNT162b2 at all concentrations tested (0.5, 1, and 2 μg/mL), while elevated LINE-1 gene expression was detected at the highest BNT162b2 concentration (2 μg/mL). It is worth noting that gene transcription is regulated by chromatin modifications, transcription factor regulation, and the rate of RNA degradation, while translational regulation of protein involves ribosome recruitment on the initiation codon, modulation of peptide elongation, termination of protein synthesis, or ribosome biogenesis. These two processes are controlled by different mechanisms, and therefore they may not always show the same change patterns in response to external challenges. The exact regulation of LINE-1 activity in response to BNT162b2 merits further study.The cell model that we used in this study is a carcinoma cell line, with active DNA replication which differs from non-dividing somatic cells. It has also been shown that Huh7 cells display significant different gene and protein expression including upregulated proteins involved in RNA metabolism [56]. However, cell proliferation is also active in several human tissues such as the bone marrow or basal layers of epithelia as well as during embryogenesis, and it is therefore necessary to examine the effect of BNT162b2 on genomic integrity under such conditions. Furthermore, effective retrotransposition of LINE-1 has also been reported in non-dividing and terminally differentiated cells, such as human neurons [57,58].The Pfizer EMA assessment report also showed that BNT162b2 distributes in the spleen (<1.1%), adrenal glands (<0.1%), as well as low and measurable radioactivity in the ovaries and testes (<0.1%) [26]. Furthermore, no data on placental transfer of BNT162b2 is available from Pfizer EMA assessment report. Our results showed that BNT162b2 mRNA readily enters Huh7 cells at a concentration (0.5 µg/mL) corresponding to 0.5% of the local injection site concentration, induce changes in LINE-1 gene and protein expression, and within 6 h, reverse transcription of BNT162b2 can be detected. It is therefore important to investigate further the effect of BNT162b2 on other cell types and tissues both in vitro and in vivo.

5. Conclusions

Our study is the first in vitro study on the effect of COVID-19 mRNA vaccine BNT162b2 on human liver cell line. We present evidence on fast entry of BNT162b2 into the cells and subsequent intracellular reverse transcription of BNT162b2 mRNA into DNA.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/cimb44030073/s1.

Author Contributions

M.A., F.O.F., D.Y., M.B. and C.L. performed in vitro experiments. M.A. and F.O.F. performed data analysis. M.R. and Y.D.M. contributed to the implementation of the research, designed, and supervised the study. Y.D.M. wrote the paper with input from all authors. All authors have read and agreed to the published version of the manuscript.

Funding

This study was supported by the Swedish Research Council, Strategic Research Area Exodiab, Dnr 2009-1039, the Swedish Government Fund for Clinical Research (ALF) and the foundation of Skåne University Hospital.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All data supporting the findings of this study are available within the article and supporting information.

Acknowledgments

The authors thank Sven Haidl, Maria Josephson, Enming Zhang, Jia-Yi Li, Caroline Haikal, and Pradeep Bompada for their support to this study.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. World Health Organization. Coronavirus (COVID-19) Dashboard. Available online: https://covid19.who.int/ (accessed on 22 February 2022).
  2. Mulligan, M.J.; Lyke, K.E.; Kitchin, N.; Absalon, J.; Gurtman, A.; Lockhart, S.; Neuzil, K.; Raabe, V.; Bailey, R.; Swanson, K.A.; et al. Phase I/II study of COVID-19 RNA vaccine BNT162b1 in adults. Nature 2020586, 589–593. [Google Scholar] [CrossRef] [PubMed]
  3. Walsh, E.E.; Frenck, R.W., Jr.; Falsey, A.R.; Kitchin, N.; Absalon, J.; Gurtman, A.; Lockhart, S.; Neuzil, K.; Mulligan, M.J.; Bailey, R.; et al. Safety and Immunogenicity of Two RNA-Based COVID-19 Vaccine Candidates. N. Engl. J. Med. 2020383, 2439–2450. [Google Scholar] [CrossRef] [PubMed]
  4. Polack, F.P.; Thomas, S.J.; Kitchin, N.; Absalon, J.; Gurtman, A.; Lockhart, S.; Perez, J.L.; Perez Marc, G.; Moreira, E.D.; Zerbini, C.; et al. Safety and Efficacy of the BNT162b2 mRNA COVID-19 Vaccine. N. Engl. J. Med. 2020383, 2603–2615. [Google Scholar] [CrossRef] [PubMed]
  5. Harris, R.J.; Hall, J.A.; Zaidi, A.; Andrews, N.J.; Dunbar, J.K.; Dabrera, G. Effect of Vaccination on Household Transmission of SARS-CoV-2 in England. N. Engl. J. Med. 2021385, 759–760. [Google Scholar] [CrossRef]
  6. Butt, A.A.; Omer, S.B.; Yan, P.; Shaikh, O.S.; Mayr, F.B. SARS-CoV-2 Vaccine Effectiveness in a High-Risk National Population in a Real-World Setting. Ann. Intern. Med. 2021174, 1404–1408. [Google Scholar] [CrossRef]
  7. Dagan, N.; Barda, N.; Kepten, E.; Miron, O.; Perchik, S.; Katz, M.A.; Hernan, M.A.; Lipsitch, M.; Reis, B.; Balicer, R.D. BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Mass Vaccination Setting. N. Engl. J. Med. 2021384, 1412–1423. [Google Scholar] [CrossRef]
  8. Rossman, H.; Shilo, S.; Meir, T.; Gorfine, M.; Shalit, U.; Segal, E. COVID-19 dynamics after a national immunization program in Israel. Nat. Med. 202127, 1055–1061. [Google Scholar] [CrossRef]
  9. Fan, B.E.; Shen, J.Y.; Lim, X.R.; Tu, T.M.; Chang, C.C.R.; Khin, H.S.W.; Koh, J.S.; Rao, J.P.; Lau, S.L.; Tan, G.B.; et al. Cerebral venous thrombosis post BNT162b2 mRNA SARS-CoV-2 vaccination: A black swan event. Am. J. Hematol. 202196, E357–E361. [Google Scholar] [CrossRef]
  10. Larson, K.F.; Ammirati, E.; Adler, E.D.; Cooper, L.T., Jr.; Hong, K.N.; Saponara, G.; Couri, D.; Cereda, A.; Procopio, A.; Cavalotti, C.; et al. Myocarditis After BNT162b2 and mRNA-1273 Vaccination. Circulation 2021144, 506–508. [Google Scholar] [CrossRef]
  11. Menni, C.; Klaser, K.; May, A.; Polidori, L.; Capdevila, J.; Louca, P.; Sudre, C.H.; Nguyen, L.H.; Drew, D.A.; Merino, J.; et al. Vaccine side-effects and SARS-CoV-2 infection after vaccination in users of the COVID Symptom Study app in the UK: A prospective observational study. Lancet Infect. Dis. 202121, 939–949. [Google Scholar] [CrossRef]
  12. Hansen, T.; Titze, U.; Kulamadayil-Heidenreich, N.S.A.; Glombitza, S.; Tebbe, J.J.; Rocken, C.; Schulz, B.; Weise, M.; Wilkens, L. First case of postmortem study in a patient vaccinated against SARS-CoV-2. Int. J. Infect. Dis. 2021107, 172–175. [Google Scholar] [CrossRef] [PubMed]
  13. Kadali, R.A.K.; Janagama, R.; Peruru, S.; Malayala, S.V. Side effects of BNT162b2 mRNA COVID-19 vaccine: A randomized, cross-sectional study with detailed self-reported symptoms from healthcare workers. Int. J. Infect. Dis. 2021106, 376–381. [Google Scholar] [CrossRef] [PubMed]
  14. Parkash, O.; Sharko, A.; Farooqi, A.; Ying, G.W.; Sura, P. Acute Pancreatitis: A Possible Side Effect of COVID-19 Vaccine. Cureus 202113, e14741. [Google Scholar] [CrossRef] [PubMed]
  15. Mazzatenta, C.; Piccolo, V.; Pace, G.; Romano, I.; Argenziano, G.; Bassi, A. Purpuric lesions on the eyelids developed after BNT162b2 mRNA COVID-19 vaccine: Another piece of SARS-CoV-2 skin puzzle? J. Eur. Acad. Dermatol. Venereol. 202135, e543–e545. [Google Scholar] [CrossRef]
  16. Lee, E.J.; Cines, D.B.; Gernsheimer, T.; Kessler, C.; Michel, M.; Tarantino, M.D.; Semple, J.W.; Arnold, D.M.; Godeau, B.; Lambert, M.P.; et al. Thrombocytopenia following Pfizer and Moderna SARS-CoV-2 vaccination. Am. J. Hematol. 202196, 534–537. [Google Scholar] [CrossRef]
  17. Ishay, Y.; Kenig, A.; Tsemach-Toren, T.; Amer, R.; Rubin, L.; Hershkovitz, Y.; Kharouf, F. Autoimmune phenomena following SARS-CoV-2 vaccination. Int. Immunopharmacol. 202199, 107970. [Google Scholar] [CrossRef]
  18. Das, B.B.; Kohli, U.; Ramachandran, P.; Nguyen, H.H.; Greil, G.; Hussain, T.; Tandon, A.; Kane, C.; Avula, S.; Duru, C.; et al. Myopericarditis following mRNA COVID-19 Vaccination in Adolescents 12 through 18 Years of Age. J. Pediatr. 2021238, 26–32.e1. [Google Scholar] [CrossRef]
  19. McLaurin-Jiang, S.; Garner, C.D.; Krutsch, K.; Hale, T.W. Maternal and Child Symptoms Following COVID-19 Vaccination Among Breastfeeding Mothers. Breastfeed. Med. 202116, 702–709. [Google Scholar] [CrossRef]
  20. Barda, N.; Dagan, N.; Ben-Shlomo, Y.; Kepten, E.; Waxman, J.; Ohana, R.; Hernan, M.A.; Lipsitch, M.; Kohane, I.; Netzer, D.; et al. Safety of the BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Setting. N. Engl. J. Med. 2021385, 1078–1090. [Google Scholar] [CrossRef]
  21. Baden, L.R.; El Sahly, H.M.; Essink, B.; Kotloff, K.; Frey, S.; Novak, R.; Diemert, D.; Spector, S.A.; Rouphael, N.; Creech, C.B.; et al. Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. N. Engl. J. Med. 2021384, 403–416. [Google Scholar] [CrossRef]
  22. Sadoff, J.; Gray, G.; Vandebosch, A.; Cardenas, V.; Shukarev, G.; Grinsztejn, B.; Goepfert, P.A.; Truyers, C.; Fennema, H.; Spiessens, B.; et al. Safety and Efficacy of Single-Dose Ad26.COV2.S Vaccine against Covid-19. N. Engl. J. Med. 2021384, 2187–2201. [Google Scholar] [CrossRef] [PubMed]
  23. Eichinger, S.; Warkentin, T.E.; Greinacher, A. Thrombotic Thrombocytopenia after ChAdOx1 nCoV-19 Vaccination. Reply. N. Engl. J. Med. 2021385, e11. [Google Scholar] [CrossRef] [PubMed]
  24. Doroftei, B.; Ciobica, A.; Ilie, O.D.; Maftei, R.; Ilea, C. Mini-Review Discussing the Reliability and Efficiency of COVID-19 Vaccines. Diagnostics 202111, 579. [Google Scholar] [CrossRef]
  25. Zhang, L.; Richards, A.; Barrasa, M.I.; Hughes, S.H.; Young, R.A.; Jaenisch, R. Reverse-transcribed SARS-CoV-2 RNA can integrate into the genome of cultured human cells and can be expressed in patient-derived tissues. Proc. Natl. Acad. Sci. USA 2021118, e2105968118. [Google Scholar] [CrossRef] [PubMed]
  26. Available online: https://www.ema.europa.eu/en/documents/assessment-report/comirnaty-epar-public-assessment-report_en.pdf (accessed on 24 February 2022).
  27. Tanaka, H.; Takata, N.; Sakurai, Y.; Yoshida, T.; Inoue, T.; Tamagawa, S.; Nakai, Y.; Tange, K.; Yoshioka, H.; Maeki, M.; et al. Delivery of Oligonucleotides Using a Self-Degradable Lipid-Like Material. Pharmaceutics 202113, 544. [Google Scholar] [CrossRef]
  28. Sedic, M.; Senn, J.J.; Lynn, A.; Laska, M.; Smith, M.; Platz, S.J.; Bolen, J.; Hoge, S.; Bulychev, A.; Jacquinet, E.; et al. Safety Evaluation of Lipid Nanoparticle-Formulated Modified mRNA in the Sprague-Dawley Rat and Cynomolgus Monkey. Vet. Pathol. 201855, 341–354. [Google Scholar] [CrossRef]
  29. Sato, Y.; Matsui, H.; Yamamoto, N.; Sato, R.; Munakata, T.; Kohara, M.; Harashima, H. Highly specific delivery of siRNA to hepatocytes circumvents endothelial cell-mediated lipid nanoparticle-associated toxicity leading to the safe and efficacious decrease in the hepatitis B virus. J. Control. Release 2017266, 216–225. [Google Scholar] [CrossRef]
  30. Heidel, J.D.; Yu, Z.; Liu, J.Y.; Rele, S.M.; Liang, Y.; Zeidan, R.K.; Kornbrust, D.J.; Davis, M.E. Administration in non-human primates of escalating intravenous doses of targeted nanoparticles containing ribonucleotide reductase subunit M2 siRNA. Proc. Natl. Acad. Sci. USA 2007104, 5715–5721. [Google Scholar] [CrossRef]
  31. Available online: https://www.cvdvaccine-us.com/ (accessed on 24 February 2022).
  32. Available online: http://bridgeslab.sph.umich.edu/protocols/index.php/Preparation_of_Tail_Samples_(for_Genotyping) (accessed on 24 February 2022).
  33. Gallud, A.; Munson, M.J.; Liu, K.; Idstrom, A.; Barriga, H.M.; Tabaei, S.; Aliakbarinodehi, N.; Ojansivu, M.; Lubart, Q.; Doutch, J.J.; et al. Time evolution of PEG-shedding and serum protein coronation determines the cell uptake kinetics and delivery of lipid nanoparticle. bioRxiv 2021. [Google Scholar] [CrossRef]
  34. World Health Organization Messenger RNA Encoding the Full-Length SARS-CoV-2 Spike Glycoprotein. 2020. Available online: https://web.archive.org/web/20210105162941/https://mednet-communities.net/inn/db/media/docs/11889.doc (accessed on 24 February 2022).
  35. Mita, P.; Wudzinska, A.; Sun, X.; Andrade, J.; Nayak, S.; Kahler, D.J.; Badri, S.; LaCava, J.; Ueberheide, B.; Yun, C.Y.; et al. LINE-1 protein localization and functional dynamics during the cell cycle. Elife 20187, e30058. [Google Scholar] [CrossRef]
  36. Sato, Y.; Kinami, Y.; Hashiba, K.; Harashima, H. Different kinetics for the hepatic uptake of lipid nanoparticles between the apolipoprotein E/low density lipoprotein receptor and the N-acetyl-d-galactosamine/asialoglycoprotein receptor pathway. J. Control. Release 2020322, 217–226. [Google Scholar] [CrossRef]
  37. Vogel, A.B.; Kanevsky, I.; Che, Y.; Swanson, K.A.; Muik, A.; Vormehr, M.; Kranz, L.M.; Walzer, K.C.; Hein, S.; Guler, A.; et al. BNT162b vaccines protect rhesus macaques from SARS-CoV-2. Nature 2021592, 283–289. [Google Scholar] [CrossRef] [PubMed]
  38. Bahl, K.; Senn, J.J.; Yuzhakov, O.; Bulychev, A.; Brito, L.A.; Hassett, K.J.; Laska, M.E.; Smith, M.; Almarsson, O.; Thompson, J.; et al. Preclinical and Clinical Demonstration of Immunogenicity by mRNA Vaccines against H10N8 and H7N9 Influenza Viruses. Mol. Ther. 201725, 1316–1327. [Google Scholar] [CrossRef] [PubMed]
  39. Bril, F.; Al Diffalha, S.; Dean, M.; Fettig, D.M. Autoimmune hepatitis developing after coronavirus disease 2019 (COVID-19) vaccine: Causality or casualty? J. Hepatol. 202175, 222–224. [Google Scholar] [CrossRef]
  40. Kazazian, H.H., Jr.; Moran, J.V. Mobile DNA in Health and Disease. N. Engl. J. Med. 2017377, 361–370. [Google Scholar] [CrossRef] [PubMed]
  41. Coffin, J.M.; Fan, H. The Discovery of Reverse Transcriptase. Annu. Rev. Virol. 20163, 29–51. [Google Scholar] [CrossRef]
  42. Lander, E.S.; Linton, L.M.; Birren, B.; Nusbaum, C.; Zody, M.C.; Baldwin, J.; Devon, K.; Dewar, K.; Doyle, M.; FitzHugh, W.; et al. Initial sequencing and analysis of the human genome. Nature 2001409, 860–921. [Google Scholar] [CrossRef]
  43. Ostertag, E.M.; Goodier, J.L.; Zhang, Y.; Kazazian, H.H., Jr. SVA elements are nonautonomous retrotransposons that cause disease in humans. Am. J. Hum. Genet. 200373, 1444–1451. [Google Scholar] [CrossRef]
  44. Hancks, D.C.; Kazazian, H.H., Jr. Active human retrotransposons: Variation and disease. Curr. Opin. Genet. Dev. 201222, 191–203. [Google Scholar] [CrossRef]
  45. Jones, R.B.; Song, H.; Xu, Y.; Garrison, K.E.; Buzdin, A.A.; Anwar, N.; Hunter, D.V.; Mujib, S.; Mihajlovic, V.; Martin, E.; et al. LINE-1 retrotransposable element DNA accumulates in HIV-1-infected cells. J. Virol. 201387, 13307–13320. [Google Scholar] [CrossRef]
  46. Macchietto, M.G.; Langlois, R.A.; Shen, S.S. Virus-induced transposable element expression up-regulation in human and mouse host cells. Life Sci. Alliance 20203, e201900536. [Google Scholar] [CrossRef] [PubMed]
  47. Yin, Y.; Liu, X.Z.; He, X.; Zhou, L.Q. Exogenous Coronavirus Interacts With Endogenous Retrotransposon in Human Cells. Front. Cell Infect. Microbiol. 202111, 609160. [Google Scholar] [CrossRef] [PubMed]
  48. Belancio, V.P.; Roy-Engel, A.M.; Deininger, P. The impact of multiple splice sites in human L1 elements. Gene 2008411, 38–45. [Google Scholar] [CrossRef] [PubMed]
  49. Dai, L.; Taylor, M.S.; O’Donnell, K.A.; Boeke, J.D. Poly(A) binding protein C1 is essential for efficient L1 retrotransposition and affects L1 RNP formation. Mol. Cell Biol. 201232, 4323–4336. [Google Scholar] [CrossRef]
  50. Servant, G.; Streva, V.A.; Derbes, R.S.; Wijetunge, M.I.; Neeland, M.; White, T.B.; Belancio, V.P.; Roy-Engel, A.M.; Deininger, P.L. The Nucleotide Excision Repair Pathway Limits L1 Retrotransposition. Genetics 2017205, 139–153. [Google Scholar] [CrossRef]
  51. Guo, H.; Chitiprolu, M.; Gagnon, D.; Meng, L.; Perez-Iratxeta, C.; Lagace, D.; Gibbings, D. Autophagy supports genomic stability by degrading retrotransposon RNA. Nat. Commun. 20145, 5276. [Google Scholar] [CrossRef]
  52. Xie, Y.; Mates, L.; Ivics, Z.; Izsvak, Z.; Martin, S.L.; An, W. Cell division promotes efficient retrotransposition in a stable L1 reporter cell line. Mob. DNA 20134, 10. [Google Scholar] [CrossRef]
  53. Shi, X.; Seluanov, A.; Gorbunova, V. Cell divisions are required for L1 retrotransposition. Mol. Cell Biol. 200727, 1264–1270. [Google Scholar] [CrossRef]
  54. Goff, S.P. Host factors exploited by retroviruses. Nat. Rev. Microbiol 20075, 253–263. [Google Scholar] [CrossRef]
  55. Suzuki, Y.; Craigie, R. The road to chromatin—Nuclear entry of retroviruses. Nat. Rev. Microbiol. 20075, 187–196. [Google Scholar] [CrossRef]
  56. Shi, J.; Wang, X.; Lyu, L.; Jiang, H.; Zhu, H.J. Comparison of protein expression between human livers and the hepatic cell lines HepG2, Hep3B, and Huh7 using SWATH and MRM-HR proteomics: Focusing on drug-metabolizing enzymes. Drug Metab. Pharmacokinet. 201833, 133–140. [Google Scholar] [CrossRef] [PubMed]
  57. Kubo, S.; Seleme, M.C.; Soifer, H.S.; Perez, J.L.; Moran, J.V.; Kazazian, H.H., Jr.; Kasahara, N. L1 retrotransposition in nondividing and primary human somatic cells. Proc. Natl. Acad. Sci. USA 2006103, 8036–8041. [Google Scholar] [CrossRef] [PubMed]
  58. Macia, A.; Widmann, T.J.; Heras, S.R.; Ayllon, V.; Sanchez, L.; Benkaddour-Boumzaouad, M.; Munoz-Lopez, M.; Rubio, A.; Amador-Cubero, S.; Blanco-Jimenez, E.; et al. Engineered LINE-1 retrotransposition in nondividing human neurons. Genome Res. 201727, 335–348. [Google Scholar] [CrossRef] [PubMed]

Gastrointestinal perforation secondary to COVID-19

Authors: Case reports and literature review Reem J. Al Argan, MBBS, SB-Med, SF-Endo, FACE, ECNU,Safi G. Alqatari, MBBS, MRCPI, MMedSc, CFP (Rheum), Abir H. Al Said, MBBS, SB-Med, CFP (Pulmo.), Raed M. Alsulaiman, MBBS, SB-Med, Abdulsalam Noor, MBBS, SB-Med, ArBIM, SF-Nephro, Lameyaa A. Al Sheekh, MD, SB-med, and Feda’a H. Al Beladi, MD

Introduction:

Corona virus disease-2019 (COVID-19) presents primarily with respiratory symptoms. However, extra respiratory manifestations are being frequently recognized including gastrointestinal involvement. The most common gastrointestinal symptoms are nausea, vomiting, diarrhea and abdominal pain. Gastrointestinal perforation in association with COVID-19 is rarely reported in the literature.

Patient concerns and diagnosis:

In this series, we are reporting 3 cases with different presentations of gastrointestinal perforation in the setting of COVID-19. Two patients were admitted with critical COVID-19 pneumonia, both required intensive care, intubation and mechanical ventilation. The first one was an elderly gentleman who had difficult weaning from mechanical ventilation and required tracheostomy. During his stay in intensive care unit, he developed Candidemia without clear source. After transfer to the ward, he developed lower gastrointestinal bleeding and found by imaging to have sealed perforated cecal mass with radiological signs of peritonitis. The second one was an obese young gentleman who was found incidentally to have air under diaphragm. Computed tomography showed severe pneumoperitoneum with cecal and gastric wall perforation. The third case was an elderly gentleman who presented with severe COVID-19 pneumonia along with symptoms and signs of acute abdomen who was confirmed by imaging to have sigmoid diverticulitis with perforation and abscess collection.

Interventions:

The first 2 cases were treated conservatively. The third one was treated surgically.

Outcome:

Our cases had a variable hospital course but fortunately all were discharged in a good clinical condition.

Conclusion:

Our aim from this series is to highlight this fatal complication to clinicians in order to enrich our understanding of this pandemic and as a result improve patients’ outcome.

Keywords: acute abdomen, acute diverticulitis, cecal mass, corona virus disease-2019, gastrointestinal perforation. 

Introduction

Corona virus disease-2019 (COVID-19) had been declared pandemic in March 2020.[1] It presents most commonly with fever in more than 80% of cases followed by respiratory symptoms which could progress to adult respiratory distress syndrome in critical cases.[2] However, extra respiratory manifestations are being frequently recognized in association with COVID-19.[3] The gastrointestinal (GI) manifestations have been reported in descriptive studies from China.[2] The most frequently reported GI symptoms are nausea, vomiting, diarrhoea, and abdominal pain.[2,4,5] However, it is rarely reported for COVID-19 to present with GI perforation. To the date of writing this report, there have been only 13 reported of GI perforation in association with COVID-19.

In this series, we are reporting 3 cases who developed GI perforation in association with COVID-19. The first 2 cases developed this fatal complication after presenting with critical COVID-19 pneumonia which required intensive care unit (ICU) admission and mechanical ventilation. The third case presented with severe COVID-19 pneumonia and was diagnosed to have GI perforation at the time of presentation. The first 2 cases were managed conservatively, and the third case was managed surgically. All of the 3 cases recovered and were discharged in good condition. We are reporting this series in order to highlight this rare but fatal complication of COVID-19. This will enhance awareness of clinicians to such complication where early diagnosis and management is crucial in order to improve the patients’ outcome.

2. Case reports

2.1. The patients provided informed consent for publication of their cases

2.1.1. First case

A 70-year old male patient known to have type 2 diabetes mellitus (T2DM), presented to our emergency department (ED) on 1st of June 2020 complaining of 3-day history of dry cough and fever. On examination: Vital signs were remarkable for tachypnea with respiratory rate (RR): 28/min and desaturation with oxygen saturation (O2 sat):81% on room air (RA) but maintained >94% on 15 litres of oxygen via a non-rebreather mask. Nasopharyngeal swab tested positive for SARS-CoV-2 polymerase chain reaction (PCR). Chest X-ray (CXR) showed bilateral lower lung fields air apace opacities (Fig. ​(Fig.1A)1A) consistent with COVID-19 pneumonia. Laboratory investigations were remarkable for high Lactate dehydrogenase (LDH), inflammatory markers, D-dimer and markedly elevated Ferritin (Table ​(Table1).1). He was started on Methylprednisolone 40 mg IV BID, Hydroxychloroquine, Ceftriaxone, Azithromycin, Oseltamivir, and Enoxaparin. After 5 days of hospital admission, he deteriorated and could not maintain saturation on non-rebreather mask, so he was shifted to ICU, intubated and mechanically ventilated. Ceftriaxone was upgraded to Meropenem in addition to same previous therapy. COVID-19 therapy was stopped after completing 10 days, but he was continued on steroids. Figure 1

The chest X-ray (CXR) of the 3 cases at the time of presentation. (A): CXR of the 1st case showing bilateral lower lung fields air apace opacities. (B): CXR of the 2nd case showing bilateral scattered air space consolidative patches throughout the lung fields predominantly over peripheral and basal lungs. (C): CXR of the 3rd case showing bilateral middle and lower zones peripheral ground glass opacities.

Table 1

The laboratory investigations of the 3 cases on presentation.

TestFirst caseSecond caseThird caseNormal range
Complete Blood Count
 White Blood cells6.44.25.7(4.0–11.0) K/uI
 Hemoglobin15.112.113.4(11.6–14.5) g/dL
 Platelets147232283(140–450) K/uI
Renal Profile
 Blood urea nitrogen101411(8.4–21) mg/dL
 Creatinine0.920.820.82(0.6–1.3) mg/dL
Liver Profile
 Total Bilirubin0.50.51.0(0.2–1.2) mg/dL
 Direct Bilirubin0.30.20.3(0.1–0.5) mg/dL
 Alanine Transferase (ALT)265241(7–55) U/L
 Aspartate transferase (AST)425052(5–34) U/L
 Alkaline phosphatase (ALP)745574(40–150) U/L
 Gamma-glutamyl transpeptidase (GGTP)532139(12–64) U/L
 Lactate dehydrogenase (LDH)434442617(81–234) U/L
Inflammatory Markers
 Erythrocyte Sedimentation rate (ESR)63101490–10 mm/h
 C-Reactive Protein (CRP)7.9218.3210.780–5 mg/dL
Others
 Ferritin1114.72565.86654.87(21.81–274.66) ng/mL
 D-Dimer0.60.411.66<=0.5 ug/mL

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Multiple trials of weaning from mechanical ventilation failed. So, tracheostomy was carried out on 20th day of ICU admission and then he was successfully extubated. During his stay in ICU, urine analysis was persistently positive for urinary tract infection secondary to Candida Abican. So, he was started on Caspofungin. At that time, blood culture was negative. After 4 days of Caspofungin, urine analysis and culture became negative. On 32nd day of hospital admission, he was stable clinically, requiring 40% FiO2 through tracheostomy mask, so he was transferred to COVID-19 isolation ward. Meropenem was stopped after 20 days of treatment. Steroid was tapered after transfer to the ward till it was discontinued after 28 days of therapy.

After 14 days of treatment with Caspofungin, follow up C-reactive protein was persistently high. Thus, full septic workup was requested and revealed Candida Albican bacteremia. At that time, urine analysis and culture were negative, Caspofungin was continued for additional 14 days. However, Candidemia persisted, so he was shifted to Anidulafungin for another 14 days. Patient at that time did not have any GI symptoms or signs. For work up of Candidemia, echocardiogram could not be done due to the hospital policy of isolation rooms. Bed side ophthalmology examination was unremarkable.

On 44th day of hospital admission, he developed fresh bleeding per rectum. Hemodynamics were stable. The bleeding resulted in acute drop of 2 g/dL of hemoglobin over 24 hours. He denied abdominal pain, abdominal examination was negative for signs of peritonitis and per rectum examination was unremarkable. Therefore, computed tomography (CT) scan of the abdomen with contrast was carried out. It showed a well-defined mass within the posterior wall of the cecum measuring 3.1 × 3.2 cm associated with discontinuous enhancement and extra-luminal air foci suggestive of complicated perforated sealed cecal mass. This is in addition to radiological findings of peritonitis (Fig. ​(Fig.22A).Figure 2

The contrast enhanced computed tomography (CT) of the abdomen of the 3 cases. (A): CT scan abdomen of the 1st case (Coronal image) showing a well-defined rounded heterogeneous enhanced soft tissue mass lesion within the posterior wall of the cecum measuring (3.1 × 3.2 cm) in anteroposterior and transverse diameter associated with discontinuous enhancement of posterior cecum wall and extra-luminal air foci suggestive of complicated perforated sealed cecum mass. This is in addition to adjacent fat stranding with free fluid as well as enhancement of peritoneal reflection suggestive of peritonitis. (B &C): CT scan abdomen of the 2nd case (Axial & Coronal images). (2B): Axial image showing moderate to severe pneumoperitoneum with air seen more tracking along the ascending colon suggestive of a wall defect in the anterior aspect of the cecum. (2C): Coronal image showing a second defect in the stomach wall. (D): CT scan abdomen of the 3rd case (Coronal image) showing severe sigmoid diverticulosis with circumferential bowel wall thickening compatible with acute diverticulitis, small amount of free air compatible with bowel perforation likely arising from the sigmoid colon and a well-defined 3.3 × 1.5 cm abscess collection adjacent to the sigmoid colon.

In consideration of his stable clinical status, absent signs of peritonitis clinically and being a sealed perforation, he was managed conservatively. So, Meropenem was resumed and Clindamycin was started. 2 days later, bleeding stopped, and he stayed stable clinically without clinical signs of peritonitis. Feeding through nasogastric tube was introduced gradually as tolerated. Antibiotics were continued for a total of 8 days. Trial of weaning from oxygen was attempted gradually which he tolerated till he was maintained on RA. After closure of tracheostomy, on 70th day of hospital admission, the patient was discharged in a good condition with a plan of follow up of cecal mass progression. However, the patient did not follow up in outpatient clinics after discharge.

2.1.2. Second case

A 37-year old male patient, morbidly obese, negative past history, presented to our ED on 11th June 2020. He reported 3-day history of shortness of breath. Vital signs were remarkable for Temperature (Temp.): 38.5 C, pulse rate (PR): 111/min, RR: 30/min and O2 sat: 80% on RA. Laboratory investigations showed high LDH, inflammatory markers and Ferritin (Table ​(Table1).1). He had positive SARS-CoV-2 PCR and CXR showed bilateral air space consolidative patches scattered throughout the lung predominantly over peripheral and basal lungs (Fig. ​(Fig.1B).1B). He was admitted to COVID-19 isolation ward as a case of COVID-19 pneumonia and started on: Triple therapy in the form of: Interferon B1, Lopinavir/Ritonavir and Ribavirin, in addition to Hydroxychloroquine, Ceftriaxone, Azithromycin, Oseltamivir, Dexamethasone 6 mg IV OD and Enoxaparin.

On the 3rd day of admission, his condition deteriorated so, he was shifted to ICU and intubated because of respiratory failure. He was maintained on same treatment for COVID-19. On 2nd day postintubation, clinically he was vitally stable without active clinical GI signs but a routine follow-up CXR showed air under the diaphragm. Therefore, abdomen CT scan with contrast was carried out and showed moderate to severe pneumoperitoneum with air tracking along the ascending colon suggestive of wall defect at the cecum, in addition to another defect noted in the stomach wall (Fig. ​(Fig.2B2B & 2C). Ceftriaxone was upgraded to Piperacillin-Tazobactam and Caspofungin was added to cover for possibility of peritonitis. Again, the patient was managed conservatively, since he was asymptomatic. He remained vitally stable without signs of peritonitis. Enteral feeding was started gradually 3 days later and on the 10th day of hospital admission, he was extubated and shifted to COVID-19 isolation ward. COVID-19 therapy was continued for 12 days.

He tolerated feeding very well. Gradual weaning of oxygen supplementation was carried out till it was discontinued. After 14 days of antibiotics, a follow up CT scan of abdomen showed interval resolution of previously seen pneumoperitoneum. He was discharged on 30th day of hospitalization in a good condition.

2.1.3. Third case

A 74-year old male patient known case of T2DM presented to our ED on 17th July 2020. He gave 3-day history of dry cough, shortness of breath and generalized colicky abdominal pain. No other pulmonary or GI symptoms. He had negative past surgical history. Vital signs were remarkable for Temp: 38.4 C, PR: 105/min, RR: 22/min and O2 sat: 90% on RA, required 3 L/min O2 through nasal cannula. Chest examination was remarkable for reduced breath sound intensity bilaterally without added sounds. Abdomen was distended with generalized tenderness and guarding. Blood tests were remarkable for high LDH, inflammatory markers, Ferritin and D-dimer (Table ​(Table1).1). PCR for SARS-COV-2 was positive and CXR showed bilateral peripheral ground glass opacities at middle and lower lung lobes (Fig. ​(Fig.1C).1C). Due to the presence of abdominal pain along with signs of acute abdomen on examination, a CT scan of the abdomen was done. It showed severe sigmoid diverticulosis with radiological findings of acute diverticulitis, free air compatible with bowel perforation likely at the sigmoid colon with 3.3 cm adjacent abscess collection (Fig. ​(Fig.22D).

Therefore, the patient was started on Piperacillin-Tazobactam, Metronidazole in addition to COVID-19 therapy. He underwent emergency exploratory laparotomy. Intra-operatively, pus and fecal peritonitis along with perforation of 0.5 cm at the distal sigmoid colon were found. So, a Hartmann’s procedure was performed. Pathology result of resected sigmoid colon revealed diverticular disease with surrounding fibrosis, moderate mucosal inflammation with mixed acute and chronic inflammatory cells, negative for malignancy.

He had smooth postoperative course. Enteral feeding was started on 3rd day postoperation and he improved clinically. After a total of 10 days of hospitalization, supplemental oxygen and antibiotics were discontinued. He was discharged on 11th day of hospitalization in a good condition.

3. Discussion

The GI manifestations are the most frequently reported extra-pulmonary manifestations of COVID-19[2] with a prevalence of 10% to 50%.[4,5] The most commonly reported GI symptoms are nausea, vomiting, diarrhoea and abdominal pain.[2,4,5] However, there have been case reports of COVID-19 cases presenting with other GI manifestations. Those include acute surgical abdomen,[6] lower GI bleeding[7] and nonbiliary pancreatitis.[8] In fact, the GI manifestations could be the presenting symptoms of COVID-19 as was reported in a case report by Siegel et al where the patient presented with abdominal pain and upon abdominal imaging, the patient was found to have pulmonary manifestations of COVID-19 in the CT scan of the lung bases.[9]

GI perforation is a surgical emergency, carries a significant mortality rate that could reach up to 90% due to peritonitis especially if complicated by multiple organ failure.[10] It can be caused by many reasons. Those include foreign body perforation, extrinsic bowel obstruction like in cases of GI tumors, intrinsic bowel obstruction like in cases of diverticulitis/appendicitis, loss of GI wall integrity such as peptic ulcer and inflammatory bowel disease in addition to GI ischemia and infections.[11] Several infections have been reported to result in GI perforation like Clostridium difficile, Mycobacterium tuberculosis, Cytomegalovirus and others.[1214] COVID-19 have been rarely reported to result in GI perforation. Till the date of writing this report only 13 cases[1523] have been reported in the literature (Table ​(Table2).2). In addition, Meini et al reported a case of pneumatosis intestinalis in association with COVID-19 but without perforation.[25]

Table 2

Summary of the previously published cases of gastrointestinal perforation in association with COVID-19.

First Author [Reference]Age/ SexCo-morbid ConditionsPresenting symptomsSeverity of COVID-19 pneumoniaCOVID-19 TherapySymptoms prompted investigations for GI perforationSite of PerforationTiming of Perforation post admissionManagement of PerforationOutcome
1Gonzalvez Guardiola et al [15]66 Y/ MMetabolic syndromeNot mentionedCriticalMethylprednisoloneTocilizumab Hydroxychloroquine AzithromycinLopinavir/RitonavirAbdominal painIncreased WBC and CRP.CecumNot mentionedRight colectomyNot mentioned
2De Nardi et al [16]53 Y/MHypertension Supra-ventricular tachycardiaFeverCoughDyspneaCriticalAnakinra Lopinavir/Ritonavir Hydroxychloroquine + AntibioticsAbdominal pain Abdominal distentionSigns of PeritonitisCecum11th day of admissionRight colectomy & ileo-transverse anastomosisDischarged Home
3Kangas-Dick et al [17]74 Y/MNegativeFeverDyspneaDry coughCriticalHydroxychloroquine +AntibioticsIncreased Oxygen requirementMarkedly distended abdomenNot specified (CT scan: Not done)5th day of admissionConservativeDied
4Galvez et al [18]59 Y/MStatus post laparoscopic Roux-en-Y gastric bypass surgeryFeverDry coughMyalgiaHeadacheDyspneaModerateMethylprednisolone + COVID-19 protocol (Not specified)Acute abdominal painWorsening dyspneaGastro-jejunal anastomosis5th day of admissionLaparoscopy& Graham Patch RepairDischarged Home
5Poggiali et al [19]54 Y/ F§HypertensionFeverDry coughGERD symptomsSevereCOVID-19 therapy (Not specified) +AntibioticsAcute chest pain Painful abdomenDiaphragm StomachAt presentationSurgical RepairNot mentioned
6Corrêa Neto et al [20]80 Y/FHypertensionCoronary artery diseaseDry coughFeverDyspneaCriticalCOVID-19 therapy(Not specified) +AntibioticsDiffuse abdominal pain & stiffnessSigmoidAt PresentationLaparotomy with recto-sigmoidectomy & terminal colostomyDied
7Rojo et al [21]54 Y/FHypertensionObesityDyslipidemiaEpilepsyCough,MyalgiaCostal painCriticalHydroxychloroquine Lopinavir/Ritonavir MethylprednisoloneTocilizumabFeverHemodynamic instabilityAnemiaCecum15th day of admissionLaparotomy with right colectomy and ileostomyDied
8Kühn et al [22]59 Y/MNot mentionedFeverNauseaAbdominal pain Fatigue, HeadacheNot specifiedNot mentionedAbdominal painJejunal diverticulumAt presentationOpen small bowel segmental resection & anastomosisDischarged Home
9Seeliger et al [23]31Y/MNot mentionedDyspneaSevereNot mentionedNot mentionedLeft colonAt presentationLeft HemicolectomyDischarged Home
1082 Y/FDyspnea, DiarrhoeaCriticalSigmoidAt presentationOpen drainage of peritonitisDied
1171 Y/FFeverSevereGangrenous appendixAt presentationLaparoscopic appendectomyDischarged Home
1280Y/MNot mentionedSevereSigmoiditisAt presentationHartmann procedureDischarged Home
1377 Y/MDyspneaCriticalDuodenal ulcer23rd day of admissionOpen duodenal exclusion, omega gastro-enteric anastomosisDied
14This Report70Y/MT2DMFeverCoughCriticalMethylprednisolone HydroxychloroquineOseltamivir Enoxaparin+AntibioticsBleeding per rectumHemoglobin DropCecal mass44th day of admissionConservativeDischarged Home
1537Y/MMorbid obesityDyspneaCriticalInterferon B1Lopinavir/RitonavirRibavirinHydroxychloroquineOseltamivirDexamethasone+AntibioticsAir under diaphragm was found incidentally in a follow up CXRCecum4th day of admissionConservativeDischarged Home
1674Y/MT2DMCoughDyspnea Abdominal pain.SevereLopinavir/RitonavirRibavirinMethylprednisolone+AntibioticsAbdominal painSigns of peritonitisSigmoid diverticulosis/diverticulitisAt presentationExploratory laparotomy with Hartmann’s procedureDischarged Home

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Severity of COVID-19 pneumonia is based on classification of severity by Ministry of Health-Saudi Arabia.[24]†Y = Year.M = Male.§F = Female.

Most of the previously reported cases presented initially with respiratory symptoms, 4 cases had also GI symptoms at presentation in the form of abdominal pain, stiffness, nausea and diarrhoea[19,20,22,23] [Table ​[Table2].2]. Eleven out of the 13 cases had severe-critical pneumonia that required either high flow oxygen, intubation or mechanical ventilation which is similar to our first 2 cases. This may indicate that GI perforation is more common in severe and critically ill COVID-19 cases. The most common symptoms which prompted investigations for bowel perforation were abdominal pain and distention [Table ​[Table2].2]. Other indications were signs of peritonitis,[16] worsening hemodynamics[17,18,21] and rising inflammatory markers.[15]

Only one of our cases had abdominal pain and tenderness at presentation. Another developed anemia due to active lower GI bleeding which is similar to the case published by Rojo et al[21] where the patient developed anemia and found to have hemoperitoneum with pericecal hematoma. This is probably explained by the site of perforation since both had cecal perforation. Our other case was diagnosed incidentally after demonstration of air under diaphragm in routine CXR. GI perforation was diagnosed from first day up to 23rd day of presentation with COVID-19 [Table ​[Table2].2]. Our patients had similar variable timing of GI perforation in relation to presentation with COVID-19. It ranged from the first day of diagnosis up to 40 days after presentation with COVID-19 pneumonia. This may tell us that GI perforation could happen at any time during the course of the infection. Our report demonstrates different presentation of GI perforation with COVID-19 since in 2 of the 3 cases, the infection predisposed to having perforation of an underlying GI lesions (cecal mass and diverticulosis). Only Kuhn et al reported similar presentation where the patient had perforation of jejunal diverticulum.[22] This may tell us that having COVID-19 predispose patients with underlying GI lesions to perforation. In addition, in our first case, we think that the source of Candidemia was most probably the bowel since it was persistent even after clearance of Candida Albican from the urine, but it was overlooked due to the absence of GI symptoms at the time of developing the Candidemia. In a study of 62 cases with peritonitis secondary to gastric perforation, Candida species was isolated in 23 cases in peritoneal fluid culture.[26] Therefore, in presence of Candidemia especially in absence of clear source, evaluation of the bowel as a potential source should always be kept in mind.

The effect of SARS-COV-2 virus on the GI system can be explained by different mechanisms. First, the virus uses the same access to enter respiratory and GI tract epithelium which are Angiotensin converting enzyme 2 receptors giving the virus the chance to replicate inside GI cells.[27] In addition, faecal-oral transmission has also been postulated, due to the presence of viral RNA in stool samples.[28] Perforation could result from altered colonic motility due to neuronal damage by the virus[29] in addition to local ischemia resulting from hypercoagulable state caused by the virus especially in critically ill patients.[30] Corrêa Neto et al reported finding ischemia of the entire GI tract during exploratory laparotomy for sigmoid perforation with COVID-19.[20] In addition, Rojo et al reported presence of microthrombi and wall necrosis in the pathology examination of his COVID-19 case with bowel perforation.[21] Other possible implicating factors are the use of Tocilizumab and high dose steroids.[21,31] Both are indicated in severe and critically ill COVID-19 cases. Steroids were used in all of our 3 cases since it is indicated in severe COVID-19 pneumonia according Saudi Arabian Ministry of health guidelines[24] but none of our patients received Tocilizumab. Some of these mechanisms could explain the higher risk of GI perforation in severe and critically ill COVID-19 patients.

The diagnosis of GI perforation is based mainly on radiological findings on CT scan. The most specific findings are segmental bowel wall thickening, focal bowel wall defect, or bubbles of extraluminal gas concentrated in close proximity to the bowel wall.[32] Treatment of GI perforation is mainly surgical in order to improve survival.[33] This is in line with the previously published cases where all were managed surgically except the one reported by Kangas-Dick et al due to the patient’s critical condition, so he was managed conservatively but unfortunately, he died.[17] However, in selected cases where there are no active signs of peritonitis, abdominal sepsis or having sealed perforation, conservative treatment is an acceptable management strategy.[34,35] This was the case in 2 of our cases who were managed conservatively. Fortunately, they did very well and had good outcome.

4. Conclusion

GI manifestations are common in patients with COVID-19. However, GI perforation is rarely reported in the literature. Severe and critically ill COVID-19 patients seem to be at a higher risk of this complication. It has a variable presentation in patients with COVID-19 ranging from incidental finding discovered only radiographically to acute abdomen. The presence of underlying GI lesion predisposes patients with COVID-19 to perforation. High index of suspicion is required in order to manage those patients further and thus, improve their outcome.

Author contributions

Conceptualization: Reem J. Al Argan, Safi G. Alqatari

Data curation: Reem J. Al Argan, Abdulsalam Noor, Lameyaa A. Al Sheekh

Writing – original draft: Reem J. Al Argan, Lameyaa A. Al Sheekh, Feda’a H. Al Beladi

Writing – review & editing: Reem J. Al Argan, Safi G. Alqatari, Abir H. Al Said, Raed M. AlsulaimanGo to:

Footnotes

Abbreviations: COVID-19 = corona virus disease-2019, CT = computed tomography, CXR = chest X-ray, ED = emergency department, GI = gastrointestinal, ICU = intensive care unit, LDH = lactate dehydrogenase, O2 sat = oxygen saturation, PCR = polymerase chain reaction, PR = Pulse rate, RA = room air, RR = respiratory rate, Temp = Temperature, T2DM = Type 2 diabetes mellitus.

How to cite this article: Al Argan RJ, Alqatari SG, Al Said AH, Alsulaiman RM, Noor A, Al Sheekh LA, Al Beladi FH. Gastrointestinal perforation secondary to COVID-19: Case reports and literature review. Medicine. 2021;100:19(e25771).

The authors have no funding and conflicts of interests to disclose.

Data sharing not applicable to this article as no datasets were generated or analyzed during the current study.

References

[1] https://www.who.int/news-room/detail/27-04-2020-who-timeline—covid-19 (Accessed September 23rd 2020). [Google Scholar][2] Guan WJ, Ni ZY, Hu Y, et al. . Clinical characteristics of coronavirus disease 2019 in China. N Eng J Med 2020;382:1708–20. [PMC free article] [PubMed] [Google Scholar][3] Lai CC, Ko WC, Lee PI, et al. . Extra-respiratory manifestations of COVID-19. Int J Anti microb Agents 2020;56:106024. [PMC free article] [PubMed] [Google Scholar][4] Pan L, Mu M, Yang P, et al. . Clinical characteristics of COVID-19 patients with digestive symptoms in Hubei, China: a descriptive, cross-sectional, multicenter study. Am J Gastroenterol 2020;115:766–73. [PMC free article] [PubMed] [Google Scholar][5] Rokkas T. Gastrointestinal involvement in COVID-19: a systematic review and meta-analysis. Ann Gastroenterol 2020;33:355–65. [PMC free article] [PubMed] [Google Scholar][6] Ashcroft J, Hudson VE, Davies RJ. COVID-19 gastrointestinal symptoms mimicking surgical presentations. Ann Med Surg (Lond) 2020;56:108–9. [PMC free article] [PubMed] [Google Scholar][7] Guotao L, Xingpeng Z, Zhihui D, et al. . SARS-CoV-2 infection presenting with hematochezia. Med Mal Infect 2020;50:293–6. [PMC free article] [PubMed] [Google Scholar][8] Hadi A, Werge M, Kristiansen KT, et al. . Coronavirus disease-19 (COVID-19) associated with severe acute pancreatitis: case report on three family members. Pancreatology 2020;20:665–7. [PMC free article] [PubMed] [Google Scholar][9] Siegel A, Chang PJ, Jarou ZJ, et al. . Lung base findings of coronavirus disease (COVID-19) on abdominal CT in patients with predominant gastrointestinal symptoms. AJR Am J Roentgenol 2020;215:1–3. [PubMed] [Google Scholar][10] Koperna T, Schulz F. Prognosis and treatment of peritonitis. Do we need new scoring systems? Arch Surg 1996;131:180–6. [PubMed] [Google Scholar][11] Langell JT, Mulvihill SJ. Gastrointestinal perforation and the acute abdomen. Med Clin North Am 2008;92:599–ix. [PubMed] [Google Scholar][12] Hayetian FD, Read TE, Brozovich M, et al. . Ileal perforation secondary to Clostridium difficult enteritis. Arch S 2006;141:97–9. [PubMed] [Google Scholar][13] Aguayo W, Gálvez P, Acosta P, et al. . Intestinal perforation due to intestinal and colonic tuberculosis in a patient with HIV, a nearly lethal complication due to lack of adequate treatment and control in a limited resource country, a case report. Int J Surg Case Rep 2019;64:45–9. [PMC free article] [PubMed] [Google Scholar][14] Kato K, Cooper M. Small bowel perforation secondary to CMV-positive terminal ileitis postrenal transplant. BMJ Case Rep 2019;12:e231662. [PMC free article] [PubMed] [Google Scholar][15] Gonzálvez Guardiola P, Díez Ares JÁ, Peris Tomás N, et al. . Intestinal perforation in patient with COVID-19 infection treated with tocilizumab and corticosteroids. Report of a clinical case. Cir Esp 2020;99:156–7. [PMC free article] [PubMed] [Google Scholar][16] De Nardi P, Parolini DC, Ripa M, et al. . Bowel perforation in a Covid-19 patient: case report. Int J Colorectal Dis 2020;35:1797–800. [PMC free article] [PubMed] [Google Scholar][17] Kangas-Dick A, Prien C, Rojas K, et al. . Gastrointestinal perforation in a critically ill patient with COVID-19 pneumonia. SAGE Open Med Case Rep 2020;8: 2050313X20940570. [PMC free article] [PubMed] [Google Scholar][18] Galvez A, King K, El Chaar M, et al. . Perforated marginal ulcer in a COVID-19 patient. Laparoscopy in these trying times. Obes Surg 2020;30:1–4. [PMC free article] [PubMed] [Google Scholar][19] Poggiali E, Vercelli A, Demichele E, et al. . Diaphragmatic rupture and gastric perforation in a patient with COVID-19 pneumonia. Eur J Case Rep Intern Med 2020;7:001738. [PMC free article] [PubMed] [Google Scholar][20] Corrêa Neto IJF, Viana KF, Silva MBSD, et al. . Perforated acute abdomen in a patient with COVID-19: an atypical manifestation of the disease. J Coloproctol 2020;40:269–72. [Google Scholar][21] Rojo M, Cano-Valderrama O, Picazo S, et al. . Gastrointestinal perforation after treatment with tocilizumab: an unexpected consequence of COVID-19 pandemic. Am Surg 2020;86:565–6. [PubMed] [Google Scholar][22] Kühn F, Klein M, Laven H, et al. . Specific management of patients with acute abdomen during the COVID-19 pandemic: a surgical perspective from Germany. Visc Med 2020;36:1–4. [PMC free article] [PubMed] [Google Scholar][23] Seeliger B, Philouze G, Cherkaoui Z, et al. . Acute abdomen in patients with SARS-CoV-2 infection or co-infection. Langenbecks Arch Surg 2020;405:861–6. [PMC free article] [PubMed] [Google Scholar][24] https://www.moh.gov.sa/Ministry/MediaCenter/Publications/Documents/MOH-therapeutic-protocol-for-COVID-19.pdf(Accessed September 5th 2020). [Google Scholar][25] Meini S, Zini C, Passaleva MT, et al. . Pneumatosis intestinalis in COVID-19. BMJ Open Gastro 2020;7:e000434. [PMC free article] [PubMed] [Google Scholar][26] Lee SC, Fung CP, Chen HY, et al. . Candida peritonitis due to peptic ulcer perforation: incidence rate, risk factors, prognosis and susceptibility to fluconazole and amphotericin B. Diagn Microbiol Infect Dis 2002;44:23–7. [PubMed] [Google Scholar][27] Zhang H, Kang Z, Gong H, Xu D,Wang J, Zifu Li Z, et al. The Digestive System Is A Potential Route of 2019-Covid infection: Bioinformatics Analysis Based On Single-Cell Transcriptomes. bioRxiv,.01.30.927806. [Google Scholar][28] Cheung KS, Hung IFN, Chan PPY, et al. . Gastrointestinal manifestations of SARS-CoV-2 infection and virus load in fecal samples from a Hong Kong Cohort: systematic review and meta-analysis. Gastroenterology 2020;59:81–95. [PMC free article] [PubMed] [Google Scholar][29] Conde G, Quintana Pájaro LD, Quintero Marzola ID, et al. . Neurotropism of SARS- CoV 2: mechanisms and manifestations. J Neurol Sci 2020;412:116824. [PMC free article] [PubMed] [Google Scholar][30] Klok FA, Kruip MJHA, van der Meer NJM, et al. . Incidence of thrombotic complications in critically ill ICU patients with COVID-19. Thromb Res 2020;191:145–7. [PMC free article] [PubMed] [Google Scholar][31] Xie F, Yun H, Bernatsky S, et al. . Brief report: risk of gastrointestinal perforation among rheumatoid arthritis patients receiving tofacitinib, tocilizumab, or other biologic treatments. Arthritis Rheumatol 2016;68:2612–7. [PMC free article] [PubMed] [Google Scholar][32] Del Gaizo AJ, Lall C, Allen BC, et al. . From esophagus to rectum: a comprehensive review of alimentary tract perforations at computed tomography. Abdom Imaging 2014;39:802–23. [PubMed] [Google Scholar][33] Hecker A, Schneck E, Röhrig R, et al. . The impact of early surgical intervention in free intestinal perforation: a time-to-intervention pilot study. World J Emerg Surg 2015;10:54. [PMC free article] [PubMed] [Google Scholar][34] Castellví J, Pi F, Sueiras A, et al. . Colonoscopic perforation: useful parameters for early diagnosis and conservative treatment. Int J Colorectal Dis 2011;26:1183–90. [PubMed] [Google Scholar][35] Donovan AJ, Berne TV, Donovan JA. Perforated duodenal ulcer: an alternative therapeutic plan. Arch Surg 1998;133:1166–71. [PubMed] [Google Scholar]

‘We Made a Big Mistake’ — COVID Vaccine Spike Protein Travels From Injection Site, Can Cause Organ Damage

Authors:  Children’s Health Defense

COVID vaccine researchers had previously assumed mRNA COVID vaccines would behave like traditional vaccines. The vaccine’s spike protein — responsible for infection and its most severe symptoms — would remain mostly in the injection site at the shoulder muscle or local lymph nodes.

But new research obtained by a group of scientists contradicts that theory, a Canadian cancer vaccine researcher said last week.

“We made a big mistake. We didn’t realize it until now,” said Byram Bridle, a viral immunologist and associate professor at University of Guelph, Ontario. “We thought the spike protein was a great target antigen, we never knew the spike protein itself was a toxin and was a pathogenic protein. So by vaccinating people we are inadvertently inoculating them with a toxin.”

Bridle, who was awarded a $230,000 grant by the Canadian government last year for research on COVID vaccine development, said he and a group of international scientists filed a request for information from the Japanese regulatory agency to get access to Pfizer’s “biodistribution study.”

Biodistribution studies are used to determine where an injected compound travels in the body, and which tissues or organs it accumulates in.

“It’s the first time ever scientists have been privy to seeing where these messenger RNA [mRNA] vaccines go after vaccination,” Bridle said in an interview with Alex Pierson where he first disclosed the data. “Is it a safe assumption that it stays in the shoulder muscle? The short answer is: absolutely not. It’s very disconcerting.”

The Sars-CoV-2 has a spike protein on its surface. That spike protein is what allows it to infect our bodies, Bridle explained. “That is why we have been using the spike protein in our vaccines,” Bridle said. “The vaccines we’re using get the cells in our bodies to manufacture that protein. If we can mount an immune response against that protein, in theory we could prevent this virus from infecting the body. That is the theory behind the vaccine.”

“However, when studying the severe COVID-19, […] heart problems, lots of problems with the cardiovascular system, bleeding and clotting, are all associated with COVID-19,”  he added. “In doing that research, what has been discovered by the scientific community, the spike protein on its own is almost entirely responsible for the damage to the cardiovascular system, if it gets into circulation.”

When the purified spike protein is injected into the blood of research animals, they experience damage to the cardiovascular system and the protein can cross the blood-brain barrier and cause damage to the brain, Bridle explained.

The biodistribution study obtained by Bridle shows the COVID spike protein gets into the blood where it circulates for several days post-vaccination and then accumulates in organs and tissues including the spleen, bone marrow, the liver, adrenal glands and in “quite high concentrations” in the ovaries.

“We have known for a long time that the spike protein is a pathogenic protein, Bridle said. “It is a toxin. It can cause damage in our body if it gets into circulation.”

A large number of studies have shown the most severe effects of SARS-CoV-2, the virus that causes COVID, such as blood clotting and bleeding, are due to the effects of the spike protein of the virus itself.

A recent study in Clinical and Infectious Diseases led by researchers at Brigham and Women’s Hospital and the Harvard Medical School measured longitudinal plasma samples collected from 13 recipients of the Moderna vaccine 1 and 29 days after the first dose and 1-28 days after the second dose.

Out of these individuals, 11 had detectable levels of SARS-CoV-2 protein in blood plasma as early as one day after the first vaccine dose, including three who had detectable levels of spike protein. A “subunit” protein called S1, part of the spike protein, was also detected.

Spike protein was detected an average of 15 days after the first injection, and one patient had spike protein detectable on day 29 –– one day after a second vaccine dose –– which disappeared two days later.

The results showed S1 antigen production after the initial vaccination can be detected by day one and is present beyond the injection site and the associated regional lymph nodes.

Assuming an average adult blood volume of approximately 5 liters, this corresponds to peak levels of approximately 0.3 micrograms of circulating free antigen for a vaccine designed only to express membrane-anchored antigen.

In a study published in Nature Neuroscience, lab animals injected with purified spike protein into their bloodstream developed cardiovascular problems. The spike protein also crossed the blood-brain barrier and caused damage to the brain.

It was a grave mistake to believe the spike protein would not escape into the blood circulation, according to Bridle. “Now, we have clear-cut evidence that the vaccines that make the cells in our deltoid muscles manufacture this protein — that the vaccine itself, plus the protein — gets into blood circulation,” he said.

Bridle said the scientific community has discovered the spike protein, on its own, is almost entirely responsible for the damage to the cardiovascular system, if it gets into circulation.

Once in circulation, the spike protein can attach to specific ACE2 receptors that are on blood platelets and the cells that line blood vessels, Bridle said. “When that happens it can do one of two things. It can either cause platelets to clump, and that can lead to clotting — that’s exactly why we’ve been seeing clotting disorders associated with these vaccines. It can also lead to bleeding,” he added.

Both clotting and bleeding are associated with vaccine-induced thrombotic thrombocytopenia (VITT). Bridle also said the spike protein in circulation would explain recently reported heart problems in vaccinated teens.

Stephanie Seneff, senior research scientists at Massachusetts Institute of Technology, said it is now clear vaccine content is being delivered to the spleen and the glands, including the ovaries and the adrenal glands, and is being shed into the medium and then eventually reaches the bloodstream causing systemic damage.

“ACE2 receptors are common in the heart and brain,” she added. “And this is how the spike protein causes cardiovascular and cognitive problems.”

Dr. J. Patrick Whelan, a pediatric rheumatologist, warned the U.S. Food and Drug Administration (FDA) in December mRNA vaccines could cause microvascular injury to the brain, heart, liver and kidneys in ways not assessed in safety trials.

In a public submission, Whelan sought to alert the FDA to the potential for vaccines designed to create immunity to the SARS-CoV-2 spike protein to instead cause injuries.

Whelan was concerned the mRNA vaccine technology utilized by Pfizer and Moderna had “the potential to cause microvascular injury (inflammation and small blood clots called microthrombi) to the brain, heart, liver and kidneys in ways that were not assessed in the safety trials.”

Review of COVID-19, part 1: Abdominal manifestations in adults and multisystem inflammatory syndrome in children

Authors: Devaraju Kanmaniraja,a,⁎ Jessica Kurian,a Justin Holder,a Molly Somberg Gunther,a Victoria Chernyak,b Kevin Hsu,a Jimmy Lee,a Andrew Mcclelland,a Shira E. Slasky,a Jenna Le,a and Zina J. Riccia

Abstract

The coronavirus disease 2019 (COVID -19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world, resulting in severe morbidity, mortality and economic hardship, and altering the landscape of healthcare forever. Although primarily a pulmonary illness, it can affect multiple organ systems throughout the body, sometimes with devastating complications and long-term sequelae. As we move into the second year of this pandemic, a better understanding of the pathophysiology of the virus and the varied imaging findings of COVID-19 in the involved organs is crucial to better manage this complex multi-organ disease and to help improve overall survival. This manuscript provides a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19 with the exception of unique cardiothoracic features associated with multisystem inflammatory syndrome in children (MIS-C). In Part I, extra-thoracic manifestations of COVID-19 in the abdomen in adults and features of MIS-C will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

Keywords: Abdominal imaging, COVID-19, Multisystem inflammatory syndrome

1. Abdominal findings of COVID019 in adults

The coronavirus 2019 disease (COVID-19), which originated in Wuhan, China, has quickly become a global pandemic, bringing normal life to a standstill in almost all countries around the world. The severe acute respiratory syndrome coronavirus (SARS-CoV-2) is a novel virus preceded by two other recent coronavirus infections, the severe acute respiratory syndrome coronavirus (SARS-CoV-1) and the Middle Eastern respiratory syndrome coronavirus (MERS–CoV), but it has more far-reaching and devastating consequences. As of March 2021, the COVID-19 pandemic has resulted in over 29 million cases in the United States and over 121 million cases globally. As of April 2021, it is responsible for the deaths of over half a million people in the United States and more than 2 ½ million worldwide [1]. As the disease has evolved over the past year, so has our understanding of the virus, including its pathophysiology, clinical presentation and imaging manifestations. Although COVID-19 is predominately a pulmonary illness, it is now established to have widespread extra-pulmonary involvement affecting multiple organ systems. The SARS-CoV-2 has a highly virulent spike protein which binds efficiently to the angiotensin converting enzyme 2 (ACE2) receptors which are expressed in many organs, including the airways, lung parenchyma, several organs in the abdomen, particularly the kidneys and GI system, central nervous system and the smooth and skeletal muscles of the body [2]. The virus initially induces a specific adaptive immune response, and when this response is ineffective, it results in uncontrolled inflammation, which ultimately results in tissue injury [2].

This article provides a comprehensive review of the pathophysiology and imaging findings of the extra-thoracic manifestations of COVID-19 with the exception of unique cardiothoracic features associated with multisystem inflammatory syndrome in children (MIS-C). In Part I, extra-thoracic manifestations of COVID-19 in the abdomen in adults and the varying features of multisystem inflammatory syndrome in children will be reviewed, with imaging findings summarized in Table 1Table 2 . In Part II, manifestations of COVID-19 in the musculoskeletal system, the central nervous system and central and peripheral vascular systems will be reviewed.

Table 1

Summary of abdominal imaging findings in COVID-19 in adults.

OrganImaging findings
Liver• Hepatomegaly
• Increased or coarsened echogenicity on US
• Hypoattenuation on non-contrast or contrast enhanced CT
• Periportal edema and heterogeneous enhancement on CT
• Loss of signal on opposed-phase sequences on MRI
• Portal vein thrombus
Pancreas• Features of acute interstitial pancreatitis
Biliary Tree• Biliary ductal dilatation
Kidney• Increased or heterogeneous parenchymal echogenicity on US
• Loss of corticomedullary differentiation on US
• Preserved cortical thickness
• Perinephric fat stranding and thickening of Gerota’s fascia on CT
• Wedge shaped perfusion defects on CT or MRI
• Thrombus in the renal artery or vein
Gallbladder• Distension
• Mural edema
• Sludge
• Acalculous cholecystitis
Urinary Bladder• Bladder wall thickening
• Mural hyperenhancement
• Perivesicular stranding
Bowel• Mural thickening
• Ileus
• Fluid-filled colon
• Pneumatosis intestinalis
• Portal vein gas
• Pneumoperitoneum
• Acute mesenteric ischemia
• Vascular occlusion (superior mesenteric artery, superior mesenteric vein, or portal vein)
• Mesenteric fat stranding, ascites
• Active gastrointestinal bleeding (duodenal or gastric ulcer) on CTA
• Clostridium difficile colitis
• Ischemic colitis
Spleen• Wedge shaped perfusion defects on CT or MRI
• Thrombus in the splenic artery or vein

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Table 2

Summary of imaging findings in Multisystem Inflammatory Syndrome in Children.

RegionImaging findings
Cardiothoracic• Bilateral symmetric diffuse airspace opacities with lower lobe predominance on CXR
• Diffuse ground glass opacity, septal thickening, and mild hilar lymphadenopathy on CT
• Bilateral pleural effusions
• Cardiomegaly
• Pericardial effusion
• Myocarditis pattern on cardiac MRI
Abdominal• Mesenteric lymphadenopathy, most common in right lower quadrant
• Mesenteric edema
• Ascites
• Bowel wall thickening
• Ileus
• Hepatosplenomegaly
• Gallbladder wall thickening

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2. Abdominal findings of COVID-19 in adults

2.1. Hepatobiliary derangement

Varying derangements of the liver, biliary system, gallbladder, portal vein and pancreas may occur in COVID-19 with hepatic parenchymal injury and biliary stasis reported with highest frequency. The mechanism of involvement of these structures appears to be multifactorial. The most direct form of injury results from SARS CoV-2 entry into host cells by binding to ACE2 receptors detected in several locations in the hepatobiliary system, including biliary epithelial cells (cholangiocytes), gallbladder endothelial cells and both pancreatic islet cells and exocrine glands [[3][4][5][6]].

2.1.1. Hepatic injury

Direct SARS CoV-2 entry into cholangiocytes may cause liver damage by disrupting bile acid transportation or by triggering acid accumulation resulting in liver injury [7]. Systemic inflammation, hypoxia inducing hepatitis and adverse drug reactions may incite liver injury [8]. Several drugs commonly used to treat COVID-19 patients, including acetaminophen, lopinavir and ritonavir can be hepatotoxic [9]. One study excluding COVID-19 patients receiving hepatotoxic drugs, still found patients with liver injury. Therefore, liver damage in COVID-19 patients is likely not entirely drug-induced but may also be due to acute infection [8,9]. Furthermore, since patients with chronic liver disease such as cirrhosis, autoimmune liver disease and prior liver transplantation are more susceptible to COVID-19 infection [9], underlying conditions may also contribute to liver injury.

The most frequent hepatic derangement is abnormal liver function tests reported in 16–53% of patients [10,11] and including raised levels of alanine aminotransferase, aspartate aminotransferase, and γ-glutamyl transferase with mild elevation of bilirubin. The majority of cases are mild and self-limited, with severe liver damage rare [7]. Liver injury is most prevalent in the second week of COVID-19 infection, and has a higher incidence in those with gastrointestinal symptoms and more severe infection [9]. Based on a meta-analysis of hepatic autopsy findings of deceased COVID-19 patients in 7 countries, hepatic steatosis (55%), hepatic sinus congestion (35%) and vascular thrombosis (29%) were the most common [10]. In a retrospective study of abdominal imaging findings of 37 COVID-19 patients, 27% who underwent ultrasound had increased hepatic echogenicity considered to represent fatty liver with elevated liver enzymes being the most frequent indication for ultrasound [4]. It should be noted that since obesity is a major risk factor for severe COVID-19 infection, it might contribute to the frequency of steatosis identified on imaging. In another retrospective abdominal sonographic study of 30 ICU patients with COVID-19, the most common finding was hepatomegaly (56%), with most cases having increased hepatic echogenicity and elevated liver function tests [12]. In the only retrospective case-control study of 204 COVID-19 patients who underwent non-contrast chest CT scan, steatosis was found in 31.9% of cases and only 7.1% of controls [13]. Steatosis was based on a single ROI measurement in the right lobe with an attenuation value ≤ 40 HU. However, underlying risk factors for steatosis such as diabetes, obesity, hypertension and abnormal lipid profile, were not available to exclude preexisting conditions leading to steatosis. Finally, unlike in the spleen and kidney where infarcts are reported in COVID-19, hepatic infarction is not a distinct feature. This is likely due to the liver’s unique dual blood supply.

On imaging the liver may be enlarged. On ultrasound, the liver of patients with abnormal liver function tests may be coarsened and/or increased in echogenicity (Fig. 1Fig. 2 ). On CT scan, the liver may be hypoattenuated on non-contrast or contrast-enhanced exam due to steatosis (Fig. 3 ). Periportal edema and heterogeneity of hepatic enhancement may be seen on contrast-enhanced CT or MRI due to parenchymal inflammation. On MRI, loss of signal on opposed-phase sequences (Fig. 4 ) may be seen due to steatosis and periportal edema may be conspicuous on T2-weighted images or on contrast-enhanced images [7,8,14]. Periportal lymphadenopathy, typical of chronic liver disease, is not reported in COVID-19 [8]. In patients with severe COVID-19 infection, ancillary manifestations of hepatic inflammation and injury, such as parenchymal attenuation changes and abscesses may be seen (Fig. 5 ).

This Article Presents a Detailed Overview with Imaging. To View the Rest of This Analysis Click Here:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8223038/

Long covid: Damage to multiple organs presents in young, low risk patients

Authors: Gareth Iacobucci BMJ 2020; 371 doi: https://doi.org/10.1136/bmj.m4470 (Published 17 November 2020)Cite this as: BMJ 2020;371:m4470

Young, low risk patients with ongoing symptoms of covid-19 had signs of damage to multiple organs four months after initially being infected, a preprint study has suggested.1

Initial data from 201 patients suggest that almost 70% had impairments in one or more organs four months after their initial symptoms of SARS-CoV-2 infection.

The results emerged as the NHS announced plans to establish a network of more than 40 long covid specialist clinics across England this month to help patients with long term symptoms of infection.

The prospective Coverscan study examined the impact of long covid (persistent symptoms three months post infection) across multiple organs in low risk people who are relatively young and had no major underlying health problems. Assessment was done using results from magnetic resonance image scans, blood tests, and online questionnaires.

The research has not yet been peer reviewed and could not establish a causal link between organ impairment and infection. But the authors said the results had “implications not only for [the] burden of long covid but also public health approaches which have assumed low risk in young people with no comorbidities.”

The study enrolled participants at two UK sites in Oxford and London between April and August 2020. Two hundred and one individuals (mean age 44 (standard deviation 11.0) years) completed assessments after SARS-CoV-2 infection a median of 140 days after initial symptoms.

Participants were eligible if they tested positive for SARS-CoV-2 by random polymerase chain reaction swab (n=62), a positive antibody test (n=63), or had typical symptoms and were determined to have covid-19 by two independent clinicians (n=73).

The prevalence of pre-existing conditions was low (obesity: 20%, hypertension: 6%, diabetes: 2%, heart disease: 4%), and less than a fifth (18%) of individuals had been hospitalised with covid-19.

The most commonly reported ongoing symptoms—regardless of hospitalization status—were fatigue (98%), muscle ache (88%), shortness of breath (87%), and headache (83%). There was evidence of mild organ impairment in the heart (32% of patients), lungs (33%), kidneys (12%), liver (10%), pancreas (17%), and spleen (6%).

For More Information: https://www.bmj.com/content/371/bmj.m4470