[Pathologic features on gonadal changes of sexual developmental disorders in children].

To investigate the pathologic features of gonadal tissues of disorders of sexual development (DSD) in children. Fifty-three cases of gonadal developmental disorders were collected from July 2015 to August 2017 at Guangzhou Women and Children's Medical Center. Clinical manifestations, karyotypes, sex hormone levels, ultrasound imaging, histology and immunophenotype of gonadal tissues were analyzed. The age of patients ranged from 7 months to 17 years with an average of (50.7 ± 47.1) months. Social genders of the patients included 32 males and 21 females. Forty-eight patients had abnormal sex hormone levels. Clinical presentations included: toward female genitalia in 25 cases, male genitalia tendency in 17 cases and ambiguous external genitalia in 11 cases. Hypospadias was seen in 31 cases and short stature was seen in 8 cases. Chromosomal karyotyping of peripheral blood revealed 23 cases of sex chromosome disorders, 22 cases of 46 XY disorders, of which 3 cases were 5α-reductase deficiency and 8 cases of 46 XX disorders. Ultrasound examination showed cryptorchidism in 30 cases, including 16 cases of unilateral, 14 cases of bilateral and 1 case presenting a huge pelvic tumor. A total of 97 gonadal tissues from 53 cases of DSD were examined, including 9 cases of unilateral and 44 cases of bilateral gonads. Microscopically, 55 gonads (56.7%) showed dysplastic testes including 17 unilateral and 19 bilateral gonads. Fourteen were streak gonads (14.4%) including 8 unilateral and 3 bilateral gonadal tissues. Nine streak gonad with epithelial cord-like structures (9.3%) were found, of which 5 were unilateral and 2 were bilateral lesions. Seven gonads were ovotestis (7.2%), unilateral in 5 cases (the other side of the gonads of ovary in 4 cases, 1 case of dysplastic testes) and bilateral in 1 case. Seven gonads showed follicular-rich ovarian tissue (7.2%). One case showed bilateral dysplastic testes with gonadoblastoma and ectopic adrenal cortex. One case of streak gonad showed epithelial cord-like structures and undifferentiated glandular tissue embedded in malignant mixed germ cell tumors (mixed gonadoblastoma, dysgerminoma, mature teratoma and yolk sac tumor). One case had testicular microlithiasis. Uterus and fallopian tube structures were found in 11 cases. Immunohistochemical stains were performed in 15 cases. D2-40, PLAP and CKIT were expressed in germ cells and Calretinin, WT1 and inhibin were positive in Setoli cells. SALL4 and OCT3/4 were positive in 3 cases. Inhibin highlighted interstitial Leydig cells in 2 cases. GPC3 was positive in yolk sac tumor component. Gonadal dysgenesis presents a broad spectrum of gonadal phenotypes with variable degrees of differentiation. The development of bilateral gonadal tissues has certain variability. Chromosomal karyotypes have no correlation with gonadal phenotypes. Accurate histopathologic diagnosis of gonadal dysgenesis plays an important role in the treatment and prognosis of the patient.