Idiopathic juvenile osteoporosis: five-year case follow-up.

Juvenile osteoporosis is a disease of childhood and adolescence exhibiting marked clinical variability in bone change. The disease usually begins in the prepubertal period or even younger. A case of a Chinese boy suffering from back pain and generalized osteoporosis since 9 yr of age who spontaneously recovered at 14 yr of age when entering puberty is reported. The affected patient was clinically normal (as shown by X rays), until he fractured his left humerus. Metabolic studies indicated a negative calcium balance, but serum calcium, phosphorus, alkaline phosphatase, parathyroid hormone, calcifediol, calcitriol, cortisol and sex hormones were normal. X ray showed typical generalized osteoporosis with vertebral collapse. The disease markedly improved within 5 yr. No family history of inherited skeletal disorders or presenile osteoporosis was noted. The diagnosis of idiopathic juvenile osteoporosis was made.