P3681 - Myositis as an Extra-Intestinal Manifestation of Ulcerative Colitis: A Case Report and Literature Review

Talwinder Nagi, MD¹, Yousra Gheit, MS¹, Zoilo K. Suarez, MD¹, Oscar Hernandez, MD¹, Touqir Zahra, MD^2
1Florida Atlantic University Charles E. Schmidt College of Medicine, Boca Raton, FL; ²Florida Atlantic University, Boca Raton, FL

Introduction: Ulcerative Colitis (UC) is an inflammatory bowel disease (IBD) primarily affecting the large bowel mucosa, submucosa, and rectum causing friability and superficial erosions. While UC is primarily associated with gastrointestinal symptoms, extraintestinal manifestations such as arthritis, uveitis and skin findings have also been reported. Rarely, skeletal muscle involvement may also occur in 1% of patients with IBD. It is more closely associated with Crohn’s disease, as only a few cases worldwide have been reported with UC. In this case, we discuss a patient with known UC who developed new-onset myositis while admitted for a flare.

Case Description/Methods: A 75-year-old female with known UC on mesalamine presented with bloody-mucoid diarrhea and abdominal pain. She was diagnosed with a UC flare and initially treated with intravenous methylprednisolone with incremental improvement. However, on day 3 of admission, she developed diffuse body aches, dark colored urine, and found to have a creatine kinase (CK) of 7,440 IU/L and elevated AST of 354 IntlUnit/L supporting sign of muscle injury. These symptoms coincided with a presentation of myositis, which the patient never had history of. She was then put on intravenous fluids and started on prednisone. She was ultimately discharged on a prednisone taper after the resolution of her symptoms.

Discussion: A speculated mechanism linking UC and myositis involves bowel inflammation and mucosal damage leading to release of antigens that stimulate an immune response. These intestinal antigens induce antibody-forming immune complexes that can ultimately result in muscle injury. Some have thought therapy for IBD, including glucocorticoids or azathioprine, may be responsible for muscle injury. However, inflammatory myopathy could be differentiated from steroid myopathy through a muscle biopsy. Through literature review, polymyositis is the most frequently reported myositis in cases of UC involving all ages. Myositis was also found to be present in patients with dormant UC with other potential causes ruled out. Majority of the management is through steroids with most cases showing adequate resolution. Despite its rarity, myositis with elevated CK could lead to further complications if not managed appropriately. Thus, providers should be wary of myositis as an extraintestinal manifestation in patients with new-onset IBD, acute exacerbations, or even during remissions.


Disclosures:


Talwinder Nagi, MD¹, Yousra Gheit, MS¹, Zoilo K. Suarez, MD¹, Oscar Hernandez, MD¹, Touqir Zahra, MD². P3681 - Myositis as an Extra-Intestinal Manifestation of Ulcerative Colitis: A Case Report and Literature Review, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.