Undetectable maternal serum uE3 and postnatal abnormal sterol and steroid metabolism in Antley-Bixler syndrome.

Antley-Bixler syndrome (ABS) is a rare condition characterized by radiohumeral synostosis, craniosynostosis, midface hypoplasia, bowing of the femora, multiple joint contractures, and urogenital defects. Several reports have implicated errors of steroid or sterol metabolism in the pathogenesis of ABS. Evidence for this has included association with maternal luteomas, fetal 21-hydroxylase deficiency, early pregnancy exposure to high-dose fluconazole, lanosterol 14-alpha-demethylase deficiency, and a unique urinary steroid profile consistent with apparent pregnene hydroxylation deficiency (APHD).