Impact of COVID-19 on Patients with Inflammatory Bowel Disease.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in Wuhan, China, in late 2019. Responsible for the ongoing coronavirus disease 2019 (COVID-19) pandemic, SARS-CoV-2 is one of three structurally similar beta-coronaviruses that can cause a strong upregulation of cytokines referred to as cytokine release syndrome (CRS). Unresolved CRS leads to respiratory symptoms, including pneumonia, and in more severe cases, acute respiratory distress syndrome (ARDS). Although COVID-19 is widely known for these hallmark respiratory symptoms, it also impacts the gut, causing gastrointestinal (GI) tract inflammation and diarrhea. COVID-19's GI symptoms may be due to the high intestinal expression of angiotensin converting enzyme-2 receptors, which are for the binding of SARS-CoV-2 viral particles. Reports have shown that SARS-CoV-2 can be passed through fecal matter, with one study finding that 48.1% of COVID-19 patients expressed viral SARS-CoV-2 mRNA in their stool. Given that the GI tract is a target tissue affected by COVID-19, this causes concern for those with underlying GI pathologies, such as inflammatory bowel disease (IBD). Regrettably, there have been only limited studies on the impact of COVID-19 on gut health, and the impact of COVID-19 on intestinal inflammation among IBD patients remains unclear. In particular, questions regarding susceptibility to SARS-CoV-2 infection, clinical impact of COVID-19 on IBD, and the potential influence of age, sex, and immunosuppressant medications are still poorly understood. An improved understanding of these issues is needed to address the unique risks of COVID-19 among IBD patients, as well as the potential impact of SARS-CoV-2 on the host intestinal microbiota.