Ambiguous Genitalia in a Newborn With 45,X/46,X,idic(Y) Ovotesticular Disorder of Sex Development

Objective: To discuss a case of ovotesticular disorder of sex development (DSD) with ambiguous genitalia, isodicentric Y sex chromosome mosaicism, and unique histopathologic findings.Methods: We report the clinical, laboratory, imaging, and operative findings, and we highlight the pertinent features of this case. Results of hormonal and genetic testing are reviewed, and histopathologic findings are illustrated.Results: A term newborn had ambiguous genitalia and was found to have an uncommon 45,X/46,X,idic(Y) karyotype. This infant had a 2-cm phallic structure, a penoscrotal hypospadias, a gonad easily palpable in the right scrotum, and a second gonad palpable high in the left inguinal canal. On ultrasonography, both gonads appeared as normal testicles, and no mullerian structures were identified. Testosterone and dihydrotestosterone levels were normal for a male neonate. After assessment of the patient at 2 months of age because of an incarcerated left inguinal hernia, both gonads were removed and were fo...