Non-tuberculous mycobacterial osteomyelitis: an unusual cause of hip pain in immunocompetent children.

Non-tuberculous mycobacteria (NTM) are an unusual cause of osteomyelitis in immunocompetent children. Diagnosis is often difficult due to the paucity of clinical symptoms and a subtle course of the disease. NTM comprise a group of about 91 identified species of environmental mycobacteria that cause infections most frequently in immunocompromised individuals or in patients with predisposing factors. Cervical lymphadenitis is the most common presentation of NTM infection in children. Invasive and recurrent infections with these organisms have been associated with a genetic defect of the interferon gamma-receptor. We report a 3-year-old immunocompetent girl who presented a NTM osteomyelitis of the left femur. Four months before she had been treated with medical and surgical therapy for a mycobacterium avium complex cervical lymphadenitis. Polymerase chain reaction assay on bone aspirate specimens confirmed the diagnosis of mycobacterium avium osteomyelitis. The patient was treated successfully with clarithromycin and rifampicin for 6 months.