[Myositis as the first manifestation of an exacerbation of Crohn's disease].

A 19-year-old man presented with general malaise and a swelling in the right hip region and right thigh. The CT images were interpreted as an abscess of the thigh, but surgical exploration revealed a diffuse myositis, with panniculitis, necrosis and inflammation of muscle tissue, associated with an exacerbation of Crohn's disease. The disease responded well to pharmacotherapy, but later an enterocutaneous fistula developed in the direction of the hip, caused by Crohn colitis in the pelvic area, for which resection of the small intestine was carried out followed by a primary anastomosis. The primary treatment of myositis associated with inflammatory bowel disease is medicinal. Being alert to this very uncommon association may prevent unnecessary surgical intervention.