Mehrshad Abbasi
Chronic Recurrent Multifocal Osteomyelitis (CRMO) is a rare autoinflammatory bone disorder characterized by episodic bone pain, swelling, and radiologic evidence of sterile osteolytic lesions. We report the case of a 59-year-old woman (initial symptoms at age 51) with rheumatoid arthritis and remote triple-negative breast cancer who developed bilateral tibial lesions, observed serially over an eight-year follow-up period. The bone lesions appeared spontaneously, remained for variable durations, and regressed without specific treatment, paralleling pain severity. Laboratory data showed elevated inflammatory markers, while biopsy ruled out infection and malignancy. Bone scintigraphy and MRI confirmed multifocal active bone lesions, consistent with CRMO. The case highlights the diagnostic challenges of CRMO in adults, especially in the presence of other autoimmune conditions, and emphasizes the importance of long-term imaging follow-up. This case also illustrates that CRMO may mimic malignancy or infectious osteomyelitis, yet respond well to anti-inflammatory therapy alone. Early recognition can prevent unnecessary interventions.