46,XX Testicular/Ovotesticular Disorders of Sexual Development: A Single-Center Retrospective Experience

Background: 46,XX testicular/ovotesticular disorders of sexual development (T/OT DSD) are infrequent congenital conditions characterized by the presence of functional ovarian and testicular or only testicular parenchyma.

The aim of the study was to retrospectively describe clinical, hormonal, and genetic characteristics of 29 patients with 46,XX T/OT DSD (2000-2023), focusing on gonadal function, hormonal production, and long-term follow-up.

Most patients (n = 25, 86.2%) presented with atypical genitalia that suggested DSD. Median age at first assessment was 0.38 years. Sex assignment was male in 21 patients without reports of discordant gender identity. Sex assignment was recommended before expert evaluation and without adequate studies in 64% of those patients with atypical genitalia (16/25). The median external masculinization score was 8 (range 4-12). During mini-puberty, LH, testosterone, AMH, and the LH/FSH ratio were above the female reference range and no different from the normal male reference range. Spontaneous puberty was observed in one female and 10 male-assigned subjects. Among the latter, pubertal virilization occurred with signs of hypergonadotropic hypogonadism and gynecomastia. Molecular studies identified the underlying mechanism in 7 patients: SRY gene was identified in two, WT1 gene variations were detected in three others, and 2 syndromic patients harbored complex chromosomal rearrangements.

Our findings underscore the clinical and biochemical variability in 46,XX T/OT DSD. Expert evaluation and accurate diagnostic work-up are essential prior to sex assignment and to prevent misdiagnosis and inappropriate treatments. Mini-puberty was characterized by a masculinized pattern of gonadotropin secretion. The potential for functional male pubertal development should be taken into account when making sex assignment decisions.