Severe Ulcerative Colitis as a Complication of Mild COVID-19 Infection in a Vaccinated Patient.

Prior studies have proposed a direct correlation between the severity of coronavirus disease 2019 (COVID-19) and the severity of ulcerative colitis (UC). This is explained by an autoimmune response from molecular mimicry or via angiotensin-converting enzyme 2 receptor. However, we present a novel case of an inverse correlation between asymptomatic COVID-19 causing severe UC. An 84-year-old male with prior infectious colitis and asymptomatic COVID-19 presented with septic shock secondary to presumed infectious colitis. Blood workup suggested inflammatory bowel disease, which was confirmed to be UC via flexible sigmoidoscopy and pathology. He was managed successfully with oral mesalamine and high-dose intravenous steroids, which were later transitioned to an oral taper. This case reflects that the intensity of the impact of COVID-19 on the gastrointestinal system can be as variable as the immune system reaction in an already labile environment such as in the elderly and malnourished patients. Therefore, in view of a lack of reports establishing a relationship between these two entities, we aim to report a case and propose an association between mild or asymptomatic COVID-19 and severe UC.