Inflammatory bowel disease and COVID-19: A review

The World Health Organization officially declared infection with severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), leading to coronavirus disease 2019 (COVID-19) as a Public Health Emergency of International Concern (PHEIC) on 30 January 2020 and then as a pandemic on March 11, 2020 with reports of infection from most of the countries of the world [1]. COVID-19 has severely disrupted prevention and treatment for noncommunicable diseases. Severe illness can occur in otherwise healthy individuals of any age, but it predominantly occurs in adults with advanced age or certain underlying medical comorbidities [2]. Since the beginning of the health emergency, particular attention has been paid to the management of patients with chronic Inflammatory Bowel Diseases (IBDs) because they frequently are treated with immunosuppressive drugs and therefore potentially are exposed to a greater infectious risk than the general population [3]. Rabin Hamal*; Rahul Pathak; Brindeswari Kafle Bhandari; Anurag Jha; Arun Gnawali; Dinesh Koirala; Mohan Bhusal; Sashi Sharma Department of Gastroenterology, Tribhuvan University Teaching Hospital, Kathmandu, Nepal. Risk of SARS-CoV-2 infection in IBD It is important for clinicians and patients to be aware if there is a heightened risk of COVID-19 infection in IBD and if it affects the outcomes. The GI tract may be susceptible to SARS-CoV-2 infection because of widely expressed angiotensin-converting enzyme 2 (ACE2) receptors in the intestine [4]. ACE2 is a receptor for SARS-CoV-2 virus, and digestive symptoms associated with SARS-CoV-2 infection may be caused by direct viral attack as well as tissue and organ damage due to the immune response [5]. Staining of tissue specimens from patients with COVID-19 demonstrated that the positive areas were mainly distributed in the cytoplasm of gastric and intestinal epithelial cells and the cilia of glandular epithelial cells [5]. ACE2 receptor appears to be differentially expressed in inflamed IBD mucosa with upregulation in the colon but downregulation in the small intestine [6,7]. SARS-CoV-2 receptor expression also appears to be impacted by IBD medications, with infliximab notably being associated with decreased ACE2 [8].