Effectiveness of the treatment with intravenous pamidronate in calcinosis in juvenile dermatomyositis.

Objective: Calcinosis is a frequent finding in up to 40% of children with juvenile dermatomyositis (JDM). Different treatments (aluminum hydroxide, diltiazem, probenecid, alendronate, etc.) have been used in an attempt to clear calcinosis and to avoid the onset of new calcium deposition, but none has been clearly effective. Pamidronate is a nitrogen-containing bisphosphonate with a potent inhibiting bone resorption effect that has been used to treat osteoporosis in children. We report three children with JDM who developed calcinosis and who received intravenous pamidronate with good results.

Methods: All three patients met the Bohan and Peter diagnostic criteria for JDM. Intravenous pamidronate was given at 1 mg/kg/day on three consecutive days every three months according to the protocol established by Glorieux et al. for osteoporosis treatment in osteogenesis imperfecta.

Results: The calcinosis which developed in all three patients improved. No important adverse events were observed.

Conclusion: In all three cases, calcinosis significantly decreased, and even totally cleared in patient 1. Total clearance of pre-existing calcinosis in JDM with pamidronate therapy has not been previously described with any of the aforementioned treatments. The advantage of treatment with pamidronate compared to treatment with alendronate is that intravenous administration does not produce esophagitis, the most frequent adverse event when orally administering bisphosphonates. Our results strongly suggest that therapy with intravenous pamidronate in conjunction with good disease control with DMARD therapy is an apparently safe and effective treatment for calcinosis management in JDM.