Objective To explore the clinical and genetic characteristics of 17α-hydroxylase/17, 20-lyase deficiency(17OHD) in childhood.

Methods The clinical features, laboratory and imaging examination results, gene mutation characteristics of 4 children diagnosed with 17OHD in Children's Hospital Affiliated to Zhengzhou University from January 2016 to December 2022 were retrospectively analyzed, and the literature was reviewed and summarized.

Results At the time of diagnosis, the age of 4 children ranged from 11 months and 21 days to 10 years and 6 months. All patients had karyotypes of 46, XY. Social gender: 1 male and 3 females. The chief complaints were 1 case of short penis, 1 case of inguinal mass, and 2 cases of grade 2 hypertension, and 3 cases of testes were found in scrotum, groin and inguinal annulus, respectively. The levels of cortisol, testosterone, and androstenedione decreased at 8 o'clock in 4 children, while the levels of adrenocorticotropic hormone, progesterone, luteinizing hormone, and follicle stimulating hormone increased. 17 hydroxyprogesterone was normal. Mild decrease in blood potassium levels (3.44-3.48 mmol/L) was found in 3 cases. One case of CYP17A1 homozygous mutation and three cases of compound heterozygous mutation were found, among which c.563 A > G and c.436+1G > T were new mutation sites that had not been reported in the past, and 3 cases had c.985_987delinsAA mutation. All 4 cases received oral hydrocortisone treatment.

Conclusions Abnormal external genitalia, inguinal/labial mass and hypertension are the main features of 46, XY type 17OHD in childhood. Early hydrocortisone replacement therapy can effectively prevent the complications of 17OHD. The CYP17A1 c.985_987delinsAA mutation may be a hot topic mutation in children with 17OHD in China.