[Severe pseudomembranous colitis in patients with previous coronavirus infection]

To analyze treatment outcomes in patients with severe pseudomembranous colitis and previous coronavirus infection.

We retrospectively analyzed treatment outcomes, clinical, laboratory and histological data in convalescents of COVID-19 who admitted to the department of coloproctology for moderate-to-severe pseudomembranous colitis confirmed by endoscopic examination between 2020 and 2021.

There were 13 patients with moderate pseudomembranous colitis and 6 ones with severe pseudomembranous colitis. Mean period after recovery from coronavirus infection was 19 days. Endoscopy revealed whitish-yellow or gray raised plaques on colonic mucosa in all cases. Four patients with signs of peritonitis underwent emergency surgery. Three patients had perforation of caecum; one patient had perforation of sigmoid colon and widespread peritonitis. Two patients underwent urgent surgery for progressive toxic megacolon and ineffective therapy. Subtotal colectomy and ileostomy were performed in all cases. Histological examination revealed necrosis of not only superficial layer of colon mucosa typical for clostridial colitis, but also the entire thickness of mucosa, as well as submucosal and partially muscular layers in some cases. Mucosal crypt atrophy, fibrinoid effusion in muscular layer, diffuse polymorphonuclear cell infiltration and necrosis of muscular and submucosal nerve plexuses, as well as necrosis of vascular walls with deposition of hyaline-like structures characterize microcirculatory ischemic processes in the colon wall.

Severe pseudomembranous colitis associated with COVID-19 may not be associated with clostridial infection. Further analysis of possible ischemic etiology and pathogenesis of gastrointestinal lesions in COVID-19 is needed for preventive and therapeutic measures.