Pamidronate Therapy in Children and Adolescents with Secondary Osteoporosis

Purpose: The aim of this study was to evaluate the efficacy of pamidronate therapy in children and adolescents with secondary osteoporosis. Methods: Nine patients (7 males, 2 females, 13.2 ± 2.5 years, 10.1-17.4 years) with secondary osteoporosis who had a history of severe bone pain and/or fracture were enrolled. Intravenous pamidronate 1.5 mg/kg (0.5 mg/kg for 3 consecutive days) was given every 6 to 8 weeks for 0.86 ± 0.15 years (6 or 8 cycles). Bone mineral density (BMD) in lumbar spine and femoral neck and their Z-scores were measured before treatment, after the fourth and last cycle (sixth or eighth cycle). Results: Underlying diseases were as follows; neurofibromatosis type 1 (n = 2), epilepsy with/without cerebral palsy (N=2), autoimmune disease treated with steroid (n = 2), hematologic malignancy (n = 3). Bone pain was relieved in most of the patients after the first cycle of treatment, and no more fracture occurred thereafter. There was a significant increase in BMD Z-score of the lumbar spine and femoral neck after the last cycle of therapy, compared to baseline values (from -3.91 ± 1.79 to 1.86 ± 1.18, in L1-4 and -3.71 ± 1.83 to -2.53 ± 1.77 for femoral neck; P = 0.008 and 0.011, respectively). However, there was no significant change in BMD Z-scores between the fourth cycle and the last cycle. Fever developed in 7 out of 9 patients (77.8%), which was relieved by antipyretics. Total serum levels of calcium and phosphorus were significantly decreased (calcium, P = 0.008; phosphorus, P = 0.015) after pamidronate therapy, and three of them experienced symptomatic hypocalcemia during the first cycle. The growth velocity was normal during follow-up periods (mean, 4.47 ± 1.69 years; range, 1.05 to 6.77 years). Conclusion: In conclusion, pamidronate can be administered to the patients with secondary osteoporosis, relieving the symptoms and signs effectively and safely. However, its side effects should be monitored during treatment.