Clinical and laboratory features of temporary brittle bone disease.

Temporary brittle bone disease has been described since 1990. It is a syndrome characterised by multiple unexplained fractures in early childhood. There is growing evidence that it has natural causes and does not represent inflicted trauma. We report the clinical and laboratory features of 104 patients investigated personally between 1985 and 2000. These patients had in aggregate 976 fractures or fracture-like lesions. Our patients included disproportionate numbers of infants born preterm or as a result of multiple pregnancy. The fractures were mainly identified in the first 6 months of life and entirely within the first year of life. Most fractures were asymptomatic, particularly the many rib fractures and metaphyseal lesions. Few patients had evidence of bruising at presentation; none had clinical evidence of inflicted injury commensurate with the fractures found. In 22 patients the fractures were found in the course of investigation for unrelated symptoms. In several cases fractures took place while the children were in hospital. Unexplained bruising and sub-conjunctival haemorrhages also occurred in hospital, suggesting collagen defects. Hernias were recorded; in most these resolved spontaneously, again suggesting transient collagen defects. Among the unexplained symptoms of the patients was a history of vomiting, often projectile vomiting. Some patients had unusually blue or grey sclerae for the child's age. Many patients had abnormally large anterior fontanelles. Laboratory findings included anaemia, neutropenia and an exceptionally high serum alkaline phosphatase. Our findings reinforce the view that children with temporary brittle bone disease have a distinctive and identifiable syndrome which probably includes osteopathy of prematurity. These patients do not have osteogenesis imperfecta and are not the victims of non-accidental injury. While the causes of this syndrome remain uncertain, its distinctive features should now be more readily recognised.