Rickets of prematurity: a case report.

A case report is given, and an attempt made to summarize our knowledge about this disorder. An extremely premature infant (birth weight 750 grammes) developed progressive rickets resulting in fractures despite phosphate, calcium and calciferol (vitamin D) supplementation. The patient had mild respiratory distress syndrome but later developed broncopulmonary dysplasia. Initial biochemical evidence of rickets occurred by the 6th week of post-natal life (or 31 weeks post-conceptional age). Although the serum levels of vitamin D or 1-alphahydroxy vitamin D were not determined, it is assumed that the levels of the active metabolite was probably low since clinical, biochemical and radiologic cure of the rickets occurred following its usage.