A case of chronic recurrent multifocal osteomyelitis associated with crohn's disease.

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disease of unknown etiology, most commonly affecting the metaphysis of long bones, especially the tibia, femur and clavicle. The clinical spectrum varies from self-limited uni-or multi-focal lesions to chronic recurrent courses. Diagnosis is based on clinical, radiologic and pathological findings, is probably underdiagnosed due to poor recognition of the disease. A dysregulated innate immunity causes immune cell infiltration of the bones with subsequent osteoclast activation leading to sterile bone lesions. The molecular pathophyiology is still incompletely understood but association with other auto-inflammatory diseases such as inflammatory bowel disease (IBD), psoriasis, Wegener's disease, arthritis and synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome is interesting. CRMO can precede the symptoms of the associated disease by several years. The bone remodeling caused by CRMO can cause permanent disability. We report the case of a 10-year-old boy with CRMO in association with Crohn's disease.