Osteogenesis imperfecta

A congenital condition characterized by abnormally brittle bones that are unusually susceptible to fractures. The condition is caused by an inherited defect in the connective tissue that forms the basic material of bone. Severely affected infants are born with multiple fractures and a soft skull and do not usually survive. Others have many fractures during infancy and childhood, often as a result of normal handling and activities, and it may be difficult to distinguish the condition from child abuse. A common sign of the condition is that the whites of the eyes are abnormally thin, making them appear blue. Sufferers may also be deaf due to otosclerosis. Very mild cases may not be detected until adolescence or later. There is no specific treatment. Fractures are immobilized and usually heal quickly, but they may cause shortening and deformity of the limbs, resulting in abnormal, stunted growth. Skull fractures may cause brain damage or death. Parents may have genetic counselling to estimate the risk in future children. Severe cases can be diagnosed prenatally by ultrasound scanning.