Introduction: COVID-19 can trigger autoimmune responses via molecular mimicry. Retrospective studies of COVID-19 patients have showed up to 50% prevalence of autoimmune disease related autoantibodies. We report a patient with a history of ulcerative colitis (UC) who presented with a UC flare and COVID-19 infection was later found during evaluation as a possible trigger.
Case Description/Methods: A 31-year-old Black female presented to the hospital with abdominal pain and bloody diarrhea for 10 days. Patient also endorsed a cough productive of thick yellow sputum. Past history-ulcerative colitis on mesalamine. Physical exam-temperature-98.7F, blood pressure-138/92 mmHg, pulse-120/min, respiratory rate-18/min, O2 saturation-100%/room air, wheezing present in b/l lung fields, abdomen-nondistended, hypoactive bowel sounds, soft, tender to palpation in the left lower quadrant, no guarding/rebound or masses. Laboratory-hemoglobin 12.8 g/dL, C-reactive protein-77.8 mg/L (Ref:< 10), positive stool guaiac, SARS-CoV-2-positive, fecal calprotectin >3000 ug/g (Ref:< =49). CT of the abdomen/pelvis showed inflammatory/infectious thickening of the transverse colon likely reflecting a nonspecific colitis and a patchy area of pneumonic infiltrate in the posterior medial lung base. Intravenous fluids, Metronidazole 500 mg IV TID, Ciprofloxacin 400 mg IV Q12H and Solumedrol 60 mg IV Daily were started. Sigmoidoscopy with biopsy-moderate to severe colitis extending from the descending colon to the rectum without any dysplasia or granulomas. With IV steroids the patient reported improvement in her diarrhea and was able to tolerate her meals. Solumedrol was changed to prednisone 40 mg daily for 2 weeks and the patient was discharged with outpatient close gastroenterology follow up.
Discussion: Viral infections including COVID-19 are known to trigger autoimmunity through molecular mimicry, activating immune responses to antigenic epitopes distinct from the disease causing epitopes (epitope spreading), activating T cells in an antigen independent manner (bystander activation) or exposing cryptic epitope's (epitope which is otherwise hidden). In turn, immunosuppressive therapies used to treat autoimmune disorders may increase the risk of COVID-19. Though it is now known that COVID-19 can trigger autoimmunity further studies are required to understand the exact immunopathogenesis. Such studies may provide more insights to prevent and treat diseases of the immune system.
Figure: Figure 1- Possible mechanisms of autoimmunity in viral infections like COVID-19
Disclosures: Shobi Venkatachalam indicated no relevant financial relationships. Jayashree Nathan indicated no relevant financial relationships.
Shobi Venkatachalam, MD1, Jayashree Nathan, MD2. P2697 - COVID-19-Associated Ulcerative Colitis Flare: A Bad Breakout, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.