Clinical Profile and Treatment Outcome in Chronic Recurrent Multifocal Osteomyelitis: Experience from a Tertiary Care Center in Southern India

Objective: The objective of this study was to describe clinical and radiological features and assess the treatment response in an Indian cohort of chronic recurrent multifocal osteomyelitis (CRMO). Methods: Case records of children who were diagnosed with CRMO between January 2014 and December 2017were reviewed retrospectively. The cases were diagnosed based on the typical history along with magnetic resonance imaging (MRI). Remission was defined as resolution of symptoms along with restoration of functional status and normalization of inflammatory markers. Where available, remission was also corroborated by a repeat MRI. Clinical, radiological and treatment details were compiled. Results: 20 children who were included, all had presented with bone pain. 10 children also has associated synovitis. The mean age at diagnosis was 11.75 years. The average period from the onset of the first CRMO symptoms to the diagnosis was 17.75 months (1-60 months) the most common bones (48%) involved the pelvic bones and femur. The mean number of lesions seen was 5.0. The initial diagnosis made were either of infection related osteomyelitis or juvenile arthritis. Nine of the 20 children had undergone bone biopsies. All 20 patients were initially started on an non-steroidal anti-inflammatory drugs (NSAIDs). Only one boy responded to just NSAIDs with all other needing second-line agents. Three patients were started on pamidronate infusions initially itself (in view of spinal involvement or difficulty in weight-bearing). A total of 15 patients were started on methotrexate as the initial second-line agent. However, four patients did not have disease control with disease-modifying anti-rheumatic drugs and later required pamidronate infusions (n = 3) and anti-tumor necrosis factor agents (n = 1). Conclusion: In CRMO delays in referral and diagnosis may lead to prolonged courses of antibiotics, unnecessary radiation exposure from scans and unwarranted surgical procedures including repeated bone biopsies. MRI helps in early diagnosis and can avoid both unnecessary X-rays and bone biopsies.