ESPE Abstracts

Background: Ovotesticular disorder of sex development (OT- DSD) is a very rare disorder characterized by the presence of both ovarian and testicular tissue in the same individual. It has an approximate incidence of less than 1/20 000.The patients usually present with ambiguous genitalia and the majority show a 46,XX karyotype, with absence of the SRY sequence.

Objective and hypotheses: The study reports the cytogenetic variability and gonadal histological findings in nine patients with OT-DSD and different phenotypic features.

Method: Patients were subjected to clinical and genital examination, anthropometric measurements, pelvic sonography and genitography. Laparoscopy with gonadal biopsy was performed to determine gonadal histopathology and to exclude the presence of gonadal tumors. Conventional cytogenetic analysis and Fluorescence in situ hybridization (FISH) were used for precise detection of chromosomal abnormalities. In addition FISH on gonadal tissue biopsies were performed in three patients.

Results: Eight patients presented with ambiguous genitalia and one male patient was diagnosed after presenting with pubertal breast development. Five patients had 46,XX karyotype, one patient had a chimeric 46,XX/46,XY karyotype, two patients had isodicentric (Yq) abnormality and one patient had a complex mosaic karyotype with X;Y translocation.

Conclusion: The study empathize the importance of cytogenetic and histological investigations in DSD patients and extends the cytogenetic spectrum of OT-DSD patients.