Objective: 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.
Methods: Retrospective chart review on all children with CRMO treated with PAM. Response to PAM was measured by subjective reports and radiology including vertebral morphometry.
Results: 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.
Conclusion: 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.