In-depth exploration of differences of sex development: 5-year experience in a tertiary center.

Background: Differences/disorders of sex development (DSD) encompass a wide range of conditions. Their clinical spectrum and etiological diagnosis have not been reported in Moroccan patients. Aims: The study aims to highlight the clinical spectrum, etiological diagnosis, and management of patients with DSD. Subjects and methods: This is a retrospective study of all patients diagnosed with DSD under the age of 18 years, who were referred to the Pediatric Endocrinology Department and the Medical Genetics Laboratory at HASSAN II University Hospital of Fez between June 2018 and June 2023. Results: Out of 57 patients, 54.4% (n = 31) were diagnosed with 46,XX DSD, the most common type, while 45.6% (n = 26) had 46,XY DSD. Patients with 46,XX DSD presented earlier than those with 46,XY DSD, at a median age of 0.08 years and 0.96 years, respectively. The most commonly reported complaint was atypical genitalia. At the first presentation, the sex of rearing was already assigned to 26 males and 27 females. All patients with 46,XX DSD were diagnosed with congenital adrenal hyperplasia (CAH) at a median age of diagnosis of 0.92 years. Of these, 11 patients were raised as males. Disorders of androgen action or synthesis were more common in XY patients (69.2%). The consanguinity rate was 46.5%, and there were 19 cases with a positive family history, with 10 siblings having died. Conclusion: DSD are not rare in Morocco. Overall, CAH remains the most frequent DSD etiology. Molecular genetic analyses are needed to determine the accurate etiological distribution of DSD, especially in XY patients.