Treatment of Langerhans cell histiocytosis with pamidronate

A 14-year-old boy with longstanding multisystem Langerhans cell histiocytos is (LCH) had multifocal bone pain unresponsive to chemotherapy, corticoster oids, anti-inflammatories, and narcotic analgesics. He responded to two cyc les of intravenous pamidronate, each 90 mg per day on three consecutive day s. Two subsequent episodes of deterioration also responded to treatment. Th e pathophysiology of his bone pain and the likely mechanisms of biphosphona te action are discussed, with emphasis on the molecular and cellular basis of LCH.