Gut mucosa and COVID-19

Abstract:

SARS CoV-2 which causes COVID-19 enters the organism using ACE2 receptors and TMPRSS2. The receptors are found on the cells of the respiratory and gastrointestinal system, causing gastrointestinal symptoms in up to 53% of patients. The most common gastrointestinal symptoms are: loss of appetite, diarrhea, nausea, vomiting and abdominal pain. Gastrointestinal symptoms, especially the abdominal pain, indicate a worse clinical outcome with a higher possibility of acute respiratory distress syndrome (ARDS) development. There are two theories on how the virus enters the gastrointestinal system: the oral-fecal route, and through the vascular system. The oral-fecal route has not been confirmed since the virus has only been found in the gastrointestinal tissue and not in the stool. Detection of RNA virus in the stool dose not mean the spread of the infectious virus and causing the disease. Prolonged excretion of RNA virus in stool has been recorded in 70.3% of the patients in comparison to samples from the respiratory tract. SARS CoV-2 influences the microbiom by disrupting the normal bio-diversity with increase in opportunistic bacteria and reduction of comensal bacteria. One part of COVID-19 symptoms, like diarrhea, are explained by disturbed function of ACE2 receptor and consequent dysregulation of intestinal ion transporters and the penetration of the virus into the submucosa

Key words:
gastrointestinal mucosa; microbiota; SARS CoV-2