Gastrointestinal implications in COVID-19.

Believed to have originated from a local Huanan Seafood Wholesale Market in Wuhan, Hubei Province in China, the COVID-19 has had an unprecedented and catastrophic impact on humanity, with the WHO declaring it a global pandemic. Although the first case of COVID-19 was reported in December 2019, the primary source and intermediate host have not been confirmed, but human-to-human transmission has been universally accepted. The main mode of transmission of the virus is through respiratory droplets along with prominent respiratory system involvement. However, fecal-oral transmission due to the shedding of the virus in the gastrointestinal (GI) tract may continue for up to 10 weeks after respiratory clearance and is fast becoming important. SARS-CoV-2 shows a high affinity to ACE2 receptors, making sites of high ACE2 receptor expression, such as lungs, GI tract, brain, kidneys, heart, liver and immune system, a prime target for infection. Through this literature review, we aim to summarize the current knowledge of immunological pathways that contribute to the disease with a focus specifically on the GI tract involvement. We direct attention to the pathophysiological mechanism of involvement of the GI tract leading to symptomatic manifestations, track GI organ-specific viral loads to compare and contrast with other organ systems. We briefly detail specific treatment strategies from a GI disease standpoint and mention special considerations when there is involvement of the GI tract. © American Federation for Medical Research 2020. No commercial re-use. See rights and permissions. Published by BMJ.