Neutrophilic myositis: an extra-intestinal manifestation of ulcerative colitis

Myositis of the skeletal muscle is rarely seen as an extraintestinal manifestation of inflammatory bowel disease. We report a case of a 36-year-old man with ulcerative colitis who developed 3 episodes of steroid responsive myositis in a 4-month period. He presented with a blistering rash followed by pain and massive swelling in the right shoulder and lower extremities, with marked elevation in muscle enzymes. Diagnosis of myositis was made after a muscle biopsy, which showed neutrophilic infiltrate in the deep subcutaneous tissue and skeletal muscle. Review of the literature indicates only a few cases of myositis associated with ulcerative colitis, most of them during an acute exacerbation of the disease. However, the present patient had his first episode when the ulcerative colitis was in remission. Myositis in ulcerative colitis may present atypically, in particular mimicking pyomyositis. Clinicians should be aware of this unusual steroid-sensitive complication.