This study retrospectively analyzes the clinical data of 18 children with 45,X/46,XY differences of sex development (DSD), summarizes their clinical features and explores gonadal and Müllerian duct remnants surgical treatment methods. The clinical data of 18 children with karyotype 45,X/46,XY diagnosed in the Department of Urology of Hunan Children's Hospital from March 2011 to October 2021 were collected. All children underwent HCG stimulation testing, laparoscopic exploration, urethroscopy and bilateral gonadal biopsy. After DSD multidisciplinary team (MDT) meeting, some children underwent gonadectomy and genitalia reconstructive surgeries. The median age at first diagnosis was 1 year and 4 months (range: 10 months ∼ 16 years and 3 months). 5 children presented with female gender; they all maintained their gender assignment. The external masculinisation score (EMS) of patients raised as female was 1 (0∼3) [median (range)]. 13 children presented with male gender, 10 maintained a male gender, 3 were assigned a neutral gender. The EMS of the children raised as male was 5 (2-8) [median (range)], the EMS of the children raised as neutral gender was 4 (3.5-9.5) [median (range)]. The HCG stimulation test was positive in 11 cases, partially positive in 2 case, and negative in 5 cases. There was no relationship between the percentage of chimerism (45X ratio) and the appearance and severity of genital abnormalities. (t=-1.08, P=0.298). There was 1 case of complete gonadal dysgenesis (CGD), 10 cases of mixed gonadal dysgenesis (MGD), 5 cases of partial gonadal dysgenesis (PGD), 1 case of bilateral normal testes and 1 case of ovotesticular DSD (split-lateral type). No gonadal specimen showed germ cell tumor changes. Five cases selected to maintain the female gender, among which 3 cases underwent bilateral gonadectomy and genitalia reconstructive surgeries. Among the 10 children who chose to maintain the male gender, unilateral streak gonadectomy was performed in 4 (57.1%) with MGD, unilateral dysgenetic orchiectomy in 1 (25%) with PGD, and right ovariectomy in 1 with OTDSD. Nine of them underwent genitalia reconstructive surgeries. Four of them preserved their uterus and vagina did not have any complications during the follow-up period. Hypospadias combined with cryptorchidism and residual Müllerian duct structures is the most common phenotype of children with 45, X/46, XY DSD. Mixed gonadal dysgenesis (MGD) is the most common gonadal type. Gender assignment should be carefully selected after a thorough evaluation, while genitalia reconstructive surgery can be considered in selected patients. In children who choose the male gender, the Müllerian duct can be preserved.

Gonadal development is the first step in human reproduction. Aberrant gonadal development during the fetal period is a major cause of disorders/differences of sex development (DSD). To date, pathogenic variants of three nuclear receptor genes (NR5A1, NR0B1, and NR2F2) have been reported to cause DSD via atypical testicular development. In this review article, we describe the clinical significance of the NR5A1 variants as the cause of DSD and introduce novel findings from recent studies. NR5A1 variants are associated with 46,XY DSD and 46,XX testicular/ovotesticular DSD. Notably, both 46,XX DSD and 46,XY DSD caused by the NR5A1 variants show remarkable phenotypic variability, to which digenic/oligogenic inheritances potentially contribute. Additionally, we discuss the roles of NR0B1 and NR2F2 in the etiology of DSD. NR0B1 acts as an anti-testicular gene. Duplications containing NR0B1 result in 46,XY DSD, whereas deletions encompassing NR0B1 can underlie 46,XX testicular/ovotesticular DSD. NR2F2 has recently been reported as a causative gene for 46,XX testicular/ovotesticular DSD and possibly for 46,XY DSD, although the role of NR2F2 in gonadal development is unclear. The knowledge about these three nuclear receptors provides novel insights into the molecular networks involved in the gonadal development in human fetuses.

Disorders of sexual differentiation (DSD) with karyotype 46,XY include gonadal developmental differences such as complete gonadal dysgenesis, partial gonadal dysgenesis, testicular regression and ovotesticular sexual differentiation disorder, differences in androgen synthesis or action, such as androgen synthesis deficiency, androgen action deficits, LH receptor deficiency, AMH synthesis or action deficits, and other conditions such as severe hypospadias, cloaca estrophy, etc. Methods: A 17 years-old girl came to our attention for hirsutism, clitoral hypertrophy, primary amenorrhea, and bilateral mammary hypoplasia. According to clinical features and anamnesis, the diagnosis of 46, XY DSD was made. For diagnostic purposes, she underwent an extensive genetic analysis, hormone dosage and instrumental examinations. After a clitoridoplasty and hormone replacement treatment, the patient performs appropriate multidisciplinary follow-up and regular psychotherapy. The clinical case reported falls, according to the recent classification developed by the Chicago Consensus, within the scope of DSD with karyotype 46, XY. About 160 cases of patients with 17β-HSD3 deficiency, diagnosed at a mean age of 12 years, are described in the literature, most of them coming from Western Asia and Europe and only three cases from Eastern Asia. Clinically, about 30% of patients showed virilization, 20% clitoromegaly, ambiguous genitalia, inguinal/labial mass, 16% primary amenorrhea, and 5% absence of mammary development, features that are partly traced in the case described here. This case underscores the complexity of managing individuals with DSD. Having acquired the concept that irreversible surgery should be avoided, except in cases where failure to do so would determine health risks, the primary objective of the medical decision lies in meeting conditions aimed at harmonious sexual identification, especially regarding sexual activity and fertility, involving a team of experienced professionals (psychologists, pediatricians, surgeons, endocrinologists, radiologists), capable of promptly identifying suggestive clinical signs.

We report on an adult male initially presenting with gynecomastia and a painless scrotal mass without additional genital anomalies. Hyperpigmentation of the skin following the Blaschko's lines was identified. He underwent gonadectomy because of suspected cancer. Histological analyses revealed an ovotestis with ovulatory activity confirmed by immunohistochemistry with multiple markers. Karyotyping of cultured peripheral blood lymphocytes and a buccal smear revealed a 46,XX/46,XY chimeric constitution with different percentages. Multiple molecular analyses as well as blood typing implied a tetragametic origin. After the unilateral gonadectomy, the patient developed recurrent painful cystic swellings of the remaining gonad. Because of the wish to preserve hormonal activity as well as future fertility, the patient underwent surgical resection of a cystic gonadal area. The removed tissue showed ovulation-related features in addition to both testicular and ovarian tissue, diagnosed as an ovotestis. Testosterone therapy was initiated to suppress the persistently elevated gonadotropins and thereby suppress ovarian activity. During treatment, the recurrent pain complaints and cystic swellings ceased, although gonadotropin levels were not fully suppressed. Based on these observations, the importance of a detailed genetic and pathological diagnosis and the clinical dilemmas including the pros and cons of personalized treatment with gonadal preservative surgery are discussed.

46 XY disorders of sexual development (DSD) cover a wide spectrum of phenotypes ranging from unambiguous female genitalia to ambiguous male genitalia with hypospadias or dysgenetic gonads. Management of these patients depends on the cause of DSD, degree of feminization, age at presentation, and gender orientation. The aim of this study was to evaluate the presentation and management of patients with 46XY DSD at our center. All new and old patients of 46XY DSD attending the endocrine OPD in a period of 16 months were included in this study. Clinical, cytogenetic, hormonal, and radiological evaluation were done to identify the cause of DSD. Among 19 patients, eight were diagnosed with disorders of gonadal development (one with complete gonadal dysgenesis, four with partial gonadal dysgenesis, two with congenital bilateral anorchia, and one with ovotesticular DSD) and eight with disorders of androgen synthesis and action (one with complete androgen insensitivity syndrome [AIS], three with partial AIS and four with 5α reductase deficiency). In three patients, a definitive diagnosis could not be made. Management of patients with DSD depends on etiology, gender assignment, gender orientation, hormonal treatment, genital surgery, and consequent psychosocial implications. Due to the overlapping clinical and biochemical parameters in different subsets of DSD, only a preliminary etiological diagnosis can be made in some cases. Genetic studies with long-term follow-up are required for an accurate diagnosis.