Transient neonatal galactosaemia.

A 4 week old infant who failed to thrive was found to have galactose in his urine. Plasma galactose concentration was grossly raised (4.48 mmol/l; reference range less than 0.24 mmol/l) but red cell transferase and epimerase activities were normal. He improved when dietary lactose was excluded. Clinical and biochemical tolerance to galactose was evident by 7 months of age.