COVID-19: Focus on the lungs but do not forget the gastrointestinal tract

Abstract

The coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 was declared in the last weeks as global pandemic. Currently affecting more than 5 000 000 indi-viduals worldwide, COVID-19 is most commonly associated with symptoms caused by the acute respiratory distress syndrome (ARDS). As the number of infected indi-viduals increases, we are learning that not only lungs, but also other organs can be affected by the virus. The gastrointestinal symptoms, for example diarrhoea, vomit-ing, nausea or abdominal pain, are frequent in patients with COVID-19. Moreover, alimentary tract symptoms may precede the respiratory presentation of SARS-CoV-2 infection. This can lead to delayed diagnosis and inappropriate management of in-fected patients. In addition, SARS-CoV-2 nucleic acid can be detected in faeces of infected patients and rectal swabs are even reported to remain positive for a longer period of time than nasopharyngeal swabs. Here, we aim to provide an update on the gastrointestinal involvement of COVID-19 presenting the symptoms that can be encountered in infected patients. We address the role of angiotensin-converting en-zyme 2 (ACE2), as a functional receptor for SARS-CoV-2, which also was found in the gastrointestinal tract. Finally, we briefly discuss faecal shedding of SARS-CoV-2 and its potential role in the pathogenesis of the disease.