RT Journal Article SR Electronic T1 Neonatal rickets in one of identical twins JF Archives of Disease in Childhood JO Arch Dis Child FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP 792 OP 794 DO 10.1136/adc.57.10.792 VO 57 IS 10 A1 I Z Kovar A1 P Mayne A1 J Wallis YR 1982 UL http://adc.bmj.com/content/57/10/792.abstract AB We report a case of rickets in one of identical low birthweight twin infants. Plasma 25-hydroxycholecalciferol concentrations were normal in both infants; there was good clinical response to 1-α hydroxycholecalciferol. We suggest that there was a delay in maturation of renal 25-hydroxycholecalciferol-1α hydroxylase enzyme.