ESPE Abstracts

Background: Chimerism is the phenomenon of two or more genetically distinct cell lines (originating from different zygotes) in the same individual. In situations when the sex of the fertilised eggs is disparate, it can lead to intersex phenotypes.

Objective and hypotheses: We report a case of ovotesticular disorder of sexual development with chimerism resulting from a twin pregnancy (not involving assisted reproductive technologies).

Results: A 17-year-old adolescent from Togo presented at birth with perineoscrotal hypospadias. He was raised as a male and underwent urethroplasty at age 10. His twin sister was phenotypically normal and healthy. At 12 years he developed severe gynecomastia. He expressed male gender identity and at 17 years he asked for mastectomy. At that time he exhibited Tanner stage A₂P₄G₄ with hypospadias (after Bracka’s 1st stage hypospadias surgery), unilateral cryptorchidism (L), gynecomastia (B₅) and reported periodic hematuria. Hormonal assessment showed testosterone 4.4 nmol/l (9–32), estradiol 0.39 nmol/l (0.035–0.13), LH 12.6 U/l (2–9), FSH 7.7 U/l (2–12), AMH 10.9 pmol/l (male range 4.1–75.7) and inhibin B 35.1 pg/ml (male range 67–304). MRI revealed small yet morphologically normal right testis (3.2 ml), absent prostate, intraabdominal left ovary (2.8×2.7 cm) and presence of both an uterus (9.3 ml) and the proximal two thirds of a vagina. Karyotype indicated 46,XX[82]/46,XY[18] chimerism. Following consultation with a multidisciplinary DSD team, he underwent the 2nd stage of Bracka’s hypospadias surgery, mastectomy and laparotomy including left ovariectomy, hysterectomy, and placement of a testicular prosthesis (L). After surgery he developed compensated hypergonadotropic hypogonadism with increase of serum testosterone levels up to 12.1 nmol/l (9–32) and he exhibited spontaneous, progressive virilization.

Conclusion: Very few cases of chimeric ovotesticular DSD have been reported. Such situations raise important questions concerning sex of rearing, gender identity, fertility and risk of gonadoblastoma.