Bone metabolism in idiopathic juvenile osteoporosis: A case report

Abstract

A previously healthy 12-year-old boy developed pain on walking and x-rays showed osteoporosis. Over the next 2 years deterioration occurred, the condition became extremely severe, and he was confined to a wheelchair. After 5 years, marked kyphoscoliosis and pigeon chest deformity were present and little increase in height occurred. A wheelchair accident at the age of 17 resulted in several major long bone fractures. Iliac crest biopsies were taken at ages 15 and 17, and subjected to quantitative histology. A histochemical technique for osteoclast recognition by acid phosphatase activity showed resorption parameters to be normal. Double tetracycline labeling and histochemical identification of osteoblasts showed no abnormality of endosteal bone formation. Because of "coupling" of endosteal formation and resorption, these measurements might primarily reflect bone turnover. Failure of periosteal bone formation as shown by failure of radial growth of long bones and of epiphyseal growth was clearly evident. It is likely that osteoporosis developed in this patient due to a reduction in bone formation of unknown etiology rather than by increased bone resorption.

Effect of Pregnancy on Bone Mineral Density and Biochemical Markers of Bone Turnover in a Patient With Juvenile Idiopathic Osteoporosis

“…The PTH(7–84) peptide is known to increase markedly in renal failure (17, 18) and seems to be increased in this young woman. The significant increase in Nichols intact PTH is in contrast to the results observed in “normal” pregnancy, where Nichols intact PTH decreased significantly, reaching a nadir late in the second/early in the third trimester (19) . A pattern similar to that observed in this young lady using the Roche assay [PTH(1–84)] is the normal profile of PTH in pregnancy, suggesting that either increased PTH(7–84) is secreted by the parathyroid gland or increased metabolism of PTH(1–84) is occurring.…”

“…The significant increase in Nichols intact PTH is in contrast to the results observed in "normal" pregnancy, where Nichols intact PTH decreased significantly, reaching a nadir late in the second/ early in the third trimester. (19) A pattern similar to that observed in this young lady using the Roche assay [PTH(1-84)] is the normal profile of PTH in pregnancy, suggesting that either increased PTH(7-84) is secreted by the parathyroid gland or increased metabolism of PTH(1-84) is occurring. PTH(7-84) is thought to occupy the PTH 1 receptor, blocking the action of both PTH(1-84) and PTH(1-34), and this may contribute to the suppression of bone formation and stimulation of resorption observed during this pregnancy.…”

Deficient Bone Formation in Idiopathic Juvenile Osteoporosis: A Histomorphometric Study of Cancellous Iliac Bone

“…This is the first report comparing static and dynamic histomorphometric findings in IJO patients and age‐matched controls. Several histomorphometric reports on IJO have been published but were limited to static methods to quantify bone metabolism, described single cases, or did not have adequate control groups (15–19) . No conclusive picture has emerged from these reports.…”

“…Several histomorphometric reports on IJO have been published but were limited to static methods to quantify bone metabolism, described single cases, or did not have adequate control groups. (15)(16)(17)(18)(19) No conclusive picture has emerged from these reports. Schematically, either "increased bone resorption" or "decreased bone formation" were incriminated as causing IJO.…”

Idiopathic Juvenile Osteoporosis

“…The disease is rare and mainly affects children between 8 and 14 years old. To date, about 70 cases have been reported in the literature 6–15. The disease runs an acute course, usually over a period of 2 to 4 years, during which time there is growth arrest and multiple fractures, and then the disease remits.…”