Cytochrome P450 oxidoreductase deficiency in three patients initially regarded as having 21-hydroxylase deficiency and/or aromatase deficiency: diagnostic value of urine steroid hormone analysis.

In this study, we report on three Japanese patients with cytochrome P450 oxidoreductase (POR) deficiency (PORD). Case one was a 46,XY patient who was found to have mildly increased 17alpha-hydroxyprogesterone (17-OHP) by the neonatal mass screening. There was no maternal virilization during pregnancy, and he had no skeletal or genital abnormality. Thus, he was initially diagnosed as having nonclassical 21-hydroxylase deficiency (21-OHD). Cases two and three were 46,XX patients who were identified because of severely virilized external genitalia and maternal virilization during pregnancy. In case two, the neonatal mass screening was normal, and she had no skeletal abnormality except for mild adduction of bilateral third toes. Thus, she was initially diagnosed as having aromatase deficiency. In case three, the neonatal mass screening showed moderately increased 17-OHP, and no skeletal lesion other than rigid second metacarpophalangeal joints was identified in early infancy. Thus, she was initially suspected as having 21-OHD and/or aromatase deficiency. Subsequently, endocrine studies including urine steroid hormone analysis were performed for the assessment of glucocorticoid treatment in case one and for the virilized genitalia in cases two and three, showing adrenal and/or gonadal dysfunction characteristic of PORD. Thus, molecular analysis of POR was carried out, demonstrating homozygosity for R457H in cases one through three. The results imply that clinical features in PORD can be similar to those in 21-OHD or aromatase deficiency, and that comprehensive assessment of the pregnant course, physical examination, and adrenal and gonadal function studies is essential for the precise diagnosis of PORD.