Granulomatous osteonecrosis in Crohn's disease

A 25-year-old white woman was diagnosed with Crohn's disease involving the small and large intestines. She had a complex clinical course that required treatment with multiple pharmacological agents, including intravenous, ora l and rectal corticosteroids. She also received parenteral nutrition with l ipid emulsions. Finally, repeated intestinal resections and drainage of per ianal abscesses were required. Her disease was complicated by gallstones, u rolithiasis and hip pain. After osteonecrosis was diagnosed, joint replacem ents were performed. Review of the pathological sections from the resected hip, however, resulted in detection of granulomatous inflammation with mult inucleated giant cells - the histological 'footprint' of Crohn's disease in the gastrointestinal tract. Because prior specialized perfusion fixation p athological studies of the intestine in Crohn's disease have shown that gra nulomas are located in the walls of blood vessels, a possible mechanism for the pathogenesis of osteonecrosis in Crohn's disease is chronic microvascu lar ischemia of bone.