ESPE Abstracts

An association between Turner syndrome (TS) and Congenital Adrenal Hyperplasia (CAH) due to 21-hydroxylase deficiency is rare. TS is caused by partial or complete loss of the second sexual chromosome which leads to genital system malformation and infertility. 21-hydroxylase deficiency is a well-known cause of disorder of sexual development in genotypic female neonates.The aim of our study is to report this patient and stress this rare possibility. A 8-month-old patient suffering from both 45,X/46,XX Turner’s syndrome and virilization form of CAH was referred to our hospital. She was born spontaneously at full-term with normal birth measurement:weight 3750g(+1.21SD), length 51 cm (+0.76SD). After birth, she showed normal in growth and development until her mom found ambiguous genitalia when she was 8-month-old. Genital examination revealed a 3 cm phallus, normal external urethral orifice and incomplete fusion of labia. Laboratory investigations showed the normal levels of blood electrolytes, hyperandrogen, decreased levels of cortisol, and increased adrenocorticotropic hormone (ACTH) and 17-hydroxyprogesterone (17-OHP). 21-hydroxylase deficiency were cofirmed with the diagnosis of CAH owing to the mutation of CYP21A2 gene. Meanwhile, she could also be diagnosed with Turner syndrome by her karyotype showing a 45X/46XX pattern. Besides, the Sanger sequencing showed a negative sex-determining region Y. She is receiving hydrocotisone in a dose of 10mg/m²/day. Our recent follow-up revealed that the patient’s adrenocorticotropic hormone level were normal and her cltoris did not increase or even seemed a bit shorter. Her length was 81 cm (+2.17SD) and weight was 10.75kg (+1.22SD) when she was 1-year-old. The report suggests that it is necessary to cofirm karyotyping during investigation of patients with disorder of sexual development due to 21-hydroxylase deficiency. Additionally, TS accompanied with CAH and virilization should analyze SRY gene to exclude the possibility of hidden Y-segment. A long term follow-up about reproductive system, stature and treatment of this patient is needed.