Adham E. Obeidat, MD1, Traci Murakami, MD2, Wichit Sae-Ow, MD2; 1University of Hawaii, Honolulu, HI; 2Queens Medical Center, Honolulu, HI
Introduction: Collagenous colitis is a chronic inflammatory condition and one type of inflammatory bowel disease (IBD). Endoscopically, the colonic mucosa appears normal, and biopsy is needed for the diagnosis. Association of new onset IBD as well as exacerbation of existing colitis with the use of an IL-17 A antagonist (Secukinumab) has been reported in the literature. We report a case of a 41-year-old female with psoriatic arthritis treated with Secukinumab who developed chronic diarrhea and was found to have collagenous colitis.
Methods: A 41-year-old female with past medical history of psoriatic arthritis was referred to the GI clinic for evaluation of chronic watery diarrhea without blood or mucous, and was associated with abdominal pain, nausea and unintentional weight loss of 3 kg in one week. A gluten free and bland diet did not help her symptoms. She took Sulfasalazine intermittently, and she started taking Secukinumab 9 months before onset of diarrhea, she endorsed taking NSAID for two years and Venlafaxine for 15 years prior to onset of her diarrhea. She started taking PPI for acid reflux 5 months after her diarrhea started. Blood and stool tests were normal. Colonoscopy was done and showed moderate mucosal congestion, but otherwise normal appearing mucosa. Biopsies were taken and histopathological exam showed collagenous colitis. Patient was started on Budesonide and symptoms improved significantly, then transitioned to Azathioprine to treat both collagenous colitis and psoriatic arthritis. Discussion: Collagenous colitis presents with chronic watery diarrhea. Laboratory, imaging studies and endoscopic appearance are usually normal. Diagnosis is made by biopsy. Collagenous colitis association with other autoimmune diseases raises the probability of an immune mechanism involved in the pathogenesis of the disease. Secukinumab is currently used for the treatment of plaque psoriasis and psoriatic arthritis. Although IBD has related autoimmune characteristics, Secukinumab has not proven to be effective for this indication, and is associated with the development of new cases and flares of Crohn’s disease and ulcerative colitis, however has not been reported to be associated with the development of collagenous colitis. A protective function of IL-17 in maintaining intestinal barrier integrity has been described. Since Secukinumab targets IL-17 A it may contribute to the incident risk of collagenous colitis.
Normal colonic mucosa
Colonic mucosa with thickening of subepithelial basement membrane along with increased intraepithelial lymphocytes. Epithelial damage demonstrated by loss of mucin and irregular orientation of the nuclei is also noted.
Disclosures: Adham Obeidat indicated no relevant financial relationships. Traci Murakami indicated no relevant financial relationships. Wichit Sae-Ow indicated no relevant financial relationships.