Disorders of sexual differentiation

Gonadal dysgenesis is a distinct variety of Disorders of Sexual Differentiation (DSD) characterised by incomplete or defective formation of the gonads due to either structural or numerical anomalies of the sex chromosomes or mutations in the genes involved in the development of the gland. Here we present two such rare cases that presented during childhood. Both patients presented with ambiguous genitalia with a 45XO/46XY mosaic chromosome pattern. First case, an infant underwent laparoscopic excision of streak gonad, and a single stage hypospadias repair later. Second case, an adolescent who underwent gonadectomy as a child, presented with a mass which was excised and found to contain uterine and ovarian tissue; second stage hypospadias repair is being planned. Mixed gonadal dysgenesis usually presents with a unilateral testis, a streak gonad on the contralateral side and persistent mullerian structures. The most common karyotype noted is 45XO/46XY. These cases are known to have ambiguous external genitalia. The streak gonads have an increased malignant potential and thus, these patients should be carefully screened and followed up for gonadoblastoma.