Clinical, biochemical and genetic characteristics of children with congenital adrenal hyperplasia due to 17α-hydroxylase deficiency

Objectives: Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder, that could rarely be due to 17 alpha-hydroxylase deficiency (17 alpha OHD) and/or 17,20 lyase deficiency. Mutation of CYP17A1 gene causes deficiency of glucocorticoids and androgens but excess of mineralocorticoids. Lack of genital ambiguity in most children causes a delay in diagnosis even until puberty. Classical presentation with hypertension and hypokalemia is often not encountered. We intended to study the clinical, biochemical and genetic characteristics of children diagnosed with CAH due to 17 alpha OHD. Methods: Three children who were diagnosed with CAH due to 17 alpha OHD in our institute and on follow up were included in this retrospective study. Clinical, biochemical and genetic characteristics of these children were retrieved and studied from electronic medical records. Results: Two children were genetic females and one was genetic male, but all three were raised as females. All had hypertension at diagnosis except one but none had hypokalemia. All of them had mutation in the CYP17A1 gene. The two females responded well to oestrogen and progesterone and had adequate estrogenization clinically. Conclusions: Even though CAH due to 17 alpha OHD is quite rare, it should be considered while evaluating young individuals with hypogonadism, hypertension with or without hypokalemia. Lack of genital ambiguity and absence of classical signs at presentation does not rule out this not so uncommon condition and warrants follow up.