Nonclassic Adrenal Hyperplasia (NCAH) due to 21-hydroxylase deficiency: A cohort of 78 patients

Diagnosis of nonclassic adrenal hyperplasia (NCAH) due to 21-hydroxylase deficiency (21-OHD) may be challenging due to its occult manifestations. To characterize clinical and molecular features of NCAH patients due to 21-hydroxylase deficiency, we retrospectively included 78 NCAH patients. Their phenotype and genotype were presented and compared. The transcription activities of novel CYP21A2 promoter variants were investigated using a dual-reporter luciferase assay system. This cohort included 53 females (68 %) and 25 males (32 %). The median of onset age was 13 years old (female: 13 range from 7 to 38; male: 11 range from 6 to 71). Menstrual cycle disorder was the most common complaint in females (62 %, n = 33) and for males, it was adrenal incidentalomas (52 %, n = 13). A total of 17 (22 %) patients complained of infertility. The most frequently variant was p.Ile173Asn (20 %, n = 31). Importantly, five variants in the promoter region including − 103/− 126 and − 196/− 296 were found in 21 (27 %) patients. Patients with promoter variants showed older onset age and less impaired hormone levels of 17-hydroxyprogesterone, ACTH, progesterone, and androstenedione. Compared with the wild-type promoter, the basic transcription activity of − 103/− 126 and − 196/− 296 promoter variants were reduced by 57% and 25%, respectively. Therefore, females with menstrual cycle disorders or infertility and males with adrenal incidentaloma should be considered of NCAH due to 21-OHD. When genotyping patients with NCAH, the promoter region of the CYP21A2 gene should be also investigated.