Childhood chronic recurrent multifocal osteomyelitis: pamidronate therapy decreases pain and improves vertebral shape.

Abstract

Chronic relapsing multifocal osteomyelitis (CRMO) results in significant morbidity, especially in those with vertebral collapse. Symptomatic benefit with intravenous pamidronate (PAM) has been shown; however, few studies have demonstrated radiological benefit. We describe clinical and radiological data on 7 pediatric cases of CRMO treated with PAM. Retrospective chart review on all children with CRMO treated with PAM. Response to PAM was measured by subjective reports and radiology including vertebral morphometry. Seven patients (1 male) presented with bone pain at a median age of 8 years (range 5-14). Symptoms had been present for a median of 18 months (range 11-51) before PAM therapy. All patients had involvement of multiple nonspinal sites, 5 children had spinal involvement with vertebral fractures, and 5 had joint involvement. Six cases had symptomatic improvement within 6 months of starting PAM, which was sustained during PAM therapy (median 26 mo, range 6-41) and persisted in the 4 cases who had ceased treatment for the duration of followup (27 mo, range 18-51). The least benefit was seen in the 3 cases with synovial joint involvement. The 3 cases with spinal radiological followup showed modeling of vertebral fractures and in one patient improvement in kyphosis. No radiological improvement in nonspinal lesions was seen. PAM therapy was associated with symptomatic improvement and vertebral modeling in children with CRMO. We suggest that children with bone pain and/or spinal involvement be considered for PAM therapy early after diagnosis.