Background: Growth and body composition have not been well described in older children with biliary atresia or Alagille syndrome living with their native liver. To optimize nutritional management of these conditions it is essential to understand the normal growth characteristics.

Objectives: The purpose of this study was to evaluate and compare the growth and body composition of children, particularly school-age children, with biliary atresia and Alagille syndrome.

Methods: A single observer measured height, weight, arm anthropometry and skin fold thickness in subjects aged 1 to 12 years with biliary atresia or Alagille syndrome who had not undergone liver transplantation.

Results: Forty-six subjects (10 biliary atresia/36 Alagille syndrome) were assessed. Biliary atresia subjects were below average in height for age with normal weight and elevated body mass index. Mean fat stores were mildly depressed. The z-scores for body mass index and weight for age were inversely correlated with age. Alagille subjects were stunted and had low body weight and reduced fat and muscle stores. Body mass index z-score was inversely correlated with age despite improved cholestasis.

Conclusions: Children with Alagille syndrome had significant growth deficits as measured by weight, height and upper arm anthropometry at all ages studied. In contrast, subjects with biliary atresia had normal weights and heights. However, body mass index and weight for age z-scores were lower in the older biliary atresia subjects. Few studies of anthropometry in biliary atresia or Alagille syndrome have included the school-aged child. This study addresses this gap in knowledge and provides baseline data for nutritional interventions in these patients.