Successful treatment of dihydropteridine reductase deficiency, with an interesting effect of 5-hydroxytryptophan deficiency on sleep patterns.

We report a child in whom dihydropteridine reductase deficiency was diagnosed prenatally because of an affected sibling and who was treated from birth with apparent good response. This family has been reported before (Firgaira et al., 1980, 1981, 1983; Lipson et al., 1984; Cotton et al., 1986; Dahl et al., 1988). The parents are Lebanese Muslims who are first cousins, and their first and third children, both male, are well. The third child was diagnosed as normal in utero (Firgaira et al., 1983). The second child, the subject of an early report (Lipson et al., 1984), has dihydropteridine reductase deficiency. The dihydropteridine reductase is nonfunctional due to an amino acid insertion (Howells et al., 1990).