Critical appraisal of the mechanisms of gastrointestinal and hepatobiliary infection by COVID-19

Abstract

COVID-19 represents a novel infectious disease induced by SARS-CoV-2. It has to date affected 24,240,000 individuals and killed 2,735,805 people worldwide. The highly infectious virus attacks mainly the lung causing fever, cough and fatigue in symptomatic patients, but also pneumonia in severe cases. However, growing evidence highlights SARS-CoV-2-mediated extra-respiratory manifestations, namely gastrointestinal (GI) and hepatic complications. The detection of (i) the virus in the GI system (duodenum, colon, rectum, anal region and feces); (ii) the high expression of additional candidate co-receptors/auxiliary proteins to facilitate the virus entry; (iii) the abundant viral angiotensin-converting enzyme 2 receptor; (iv) the substantial expression of host transmembrane serine protease 2, necessary to induce virus-cell fusion; (v) the viral replication in the intestinal epithelial cells; and (vi) the primarily GI disorders in the absence of respiratory symptoms lead to increased awareness of the risk of disease transmission via the fecal-oral route. The objectives of this review are to provide a brief update of COVID-19 pathogenesis and prevalence, present a critical overview of its GI and liver complications that affect clinical COVID-19 outcomes, clarify associated mechanisms (notably microbiota-related), define whether gut/liver disorders occur more frequently among critically ill patients with COVID‐19, determine the impact of COVID-19 on pre-existing gut/liver complications and vice versa, and discuss the available strategies for prevention and treatment to improve prognosis of the patients.

Duodenal tropism of SARS-CoV-2 and clinical findings in critically ill COVID-19 patients

“…Furthermore, in situ hybridization of antisense s-SARS-CoV-2 and sense s-SARS-CoV-2 confirmed viral tropism and replication in the enterocytes of duodenal biopsies. To date, although there are data that could detect virus in small-bowel tissue, replication of SARS-CoV-2 has been demonstrated mainly in animal models [ 26 ]. Interestingly, SARS-CoV-2 RNA could not be detected in biopsies of the five patients with a mild duodenitis but only in patients with the severe progressive form.…”

“…Findings of plasma cells and lymphocytes in lamina propria of the duodenum underline microvascular small-bowel injuries, likely contributing to severe disease progression [ 26 ].…”

“…Five patients had signs of a minor duodenitis, whereas the remaining four patients (44%) presented with a severe edematous and erosive duodenitis (Fig. 1) 25 (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34) days after the diagnosis of SARS-CoV-2 infection had been made.…”

Adult Intussusception Secondary to COVID-19 Infection: A Case Report and Literature Review

“…Extra-respiratory manifestations, such as gastrointestinal (GI) symptoms are not uncommon among patients with COVID-19. 1 Intussusception is a rare cause of bowel obstruction in adults, accounting only for 1-5% of bowel obstruction adult cases. 2 While bowel obstruction has not been the mainstay of the GI COVID-19 manifestations, 25 pediatric cases, and three adult cases of intussusception have been reported so far.…”

COVID 19 y enfermedad hepática: un panorama que está siendo aclarado

“…Un 64 % de los pacientes pueden permanecer positivos para ARN en la materia fecal durante varias semanas por RT-PCR (reacción en cadena de la polimerasa con transcriptasa inversa), después de que las pruebas rinofaríngeas han sido negativas. Hallazgos histopatológicos evidencian inflamación endotelial de los vasos submucosos de la pared intestinal, con edema intersticial, infiltrado de linfocitos y células plasmáticas en la lámina propia del estómago, el duodeno y el recto de los pacientes con enfermedad severa (10) .…”