RESUMO
UNLABELLED: We report on an 8 years and 3 months old boy with severe idiopathic juvenile osteoporosis (IJO). Clinical features included multiple fractures, especially of the vertebrae, and neurological symptoms. Biological studies showed non-parathyroid hormone-mediated excessive bone resorption and massive urinary calcium loss. Although IJO is usually a self-limiting condition after puberty, the severity of our patient's manifestations required therapeutic intervention. Clodronate (dichloromethylene-bisphosphonate) was administered parenterally every 3 months for a period of 2 years. Dramatic clinical and biochemical improvement was noted within 2 weeks. All parameters of bone resorption normalised and no new fractures occurred. After 6 months of treatment, radiological improvement with healing of fractures and rebuilding of the vertebral plates was documented. Bone mineral density increased to normal within 1 year and growth velocity was accelerated. After 2 years, treatment was stopped at the age of 10 years and 3 months. One year later, back pain and increasing pain in the knee region recurred. A tibial fracture was evident and, again, bone mineral density was far below normal. Bisphosphonate medication was reinstituted leading to rapid improvement. No side-effects were observed. CONCLUSION: Parenteral clodronate therapy is effective in managing severe idiopathic juvenile osteoporosis.