Localised gastrocnemius myositis in Crohn's disease

A19-year-old woman presented with pain and tenderness in both calves associated with pyrexia and neutrophil leukocytosis. Gastrocnemius muscle biopsy showed a non-specific lymphocytic myositis and she was found to have positive c-ANCA, in the absence of other evidence of systemic vasculitis. Subsequent investigation of her gastrointestinal tract revealed extensive Crohn's disease. The myositis responded promptly to treatment with prednisolone 0.5 mg/kg. A review of the literature showed that localised calf pain in the setting of Crohn's disease can be caused by non-specific myositis, granulomatous myositis or vasculitis. It is proposed that the "gastrocnemius myalgia syndrome" be included in the typical - albeit rare - extraintestinal manifestations that may herald the appearance of inflammatory bowel disease.