RENAL OSTEODYSTROPHY

also called Renal Rickets, or Secondary Parathyroid Hyperplasia, chronic, probably hereditary disorder characterized by kidney dysfunction, bone-mineral loss and rickets-type deformities, calcifications in abnormal places, and overactivity of the parathyroid glands. Loss of calcium and retention of phosphorus occur because of the malfunctioning kidneys; this induces an overproduction of parathormone, which results in the demineralization of well-formed bones and an inability to calcify newly developing bone. The bone abnormalities develop more slowly than kidney insufficiency; if the latter is severe, death may occur in childhood before the skeletal abnormalities become apparent. If the kidney insufficiency is not total, it may cause dwarfing and frequent fractures in children; adults experience gradual softening and bowing of bones. Treatment of the disorder depends on the state of chemical balance of the patient. Kidney transplant has been successful in some cases involving severe kidney dysfunction, and removal of the malfunctioning parathyroids is sometimes effective in controlling symptoms.