ESPE Abstracts

Background: The term ‘disorder of sex development’ (DSD) includes congenital conditions in which development of chromosomal, gonadal or anatomic sex is atypical.

Materials and methods: A retrospective analysis of the 75 medical cards of patients with DSD since 2000 up to 2017 year was done. The criterion for including patients to the database was ambiguous genitalia and/or a discrepancy between the chromosomal and gonadal/genital sex. At the time of examination the number of patients aged <1 month was 17%, 1 month -<1 y.o. - 25%, 1-12 y.o. - 37%, > 12 y.o. - 21%. The results of clinical data, laboratory tests and instrumental examination were analyzed. All patients (from birth to 18 y.o.) carried out a cytogenetic test, and, if necessary, fluorescence in situ hybridization (FISH). Molecular genetic testing was done in selected group of patients with 46,XY DSD in Ukraine (n=2) and in Institute Pasteur, France (n=13), using exome sequencing.

Results and discussion: Sex chromosome DSD was diagnosed in 21.3% (n=16), 46,XY DSD- in 64% (n=48), 46,XX DSD - in 14.7% cases (n=11). The most frequent variant of the karyotype among the first group was 45,X/46,XY (n=5; 31.2%). In a group of patients with 46,XX DSD we diagnosed: testicular 46,XX DSD (n=5), 21-hydroxylase deficiency with virilization IV-V degree by Prader (n=4), 46,XX gonadal dysgenesis (n=1) and DSD in VACTER-association (n=1). In a group of patients with 46,XY DSD at first visit we suspected following clinical diagnoses (Table 1): Genetic testing in 46,XY DSD group was done in 15 (31%) cases. In 7 patients (47%) we found such genes are known to be involved in DSD as DAX-1, WT1, SRD5A2, NR5A1, HSD17B3 and AR (n=2). In 4 patients (27%) genes we found were not consistent with phenotype and their causality should be proven in further studies. In the entire cohort in 6/75 (8%) cases the gender registration of the civil sex was changed during the first 2 years of life. A multi-disciplinary team has been created for gender assignment in DSD newborns and to improve the tactics of further management, including the time of gonadectomy.

Conclusions: Further studies to identify novel genes causing DSD are required.