Pure gonadal dysgenesis with an XY chromosomal constitution (Swyer's syndrome): Report of two cases.

Two cases of Swyer's syndrome, characterized by rudimentary streaks in association with a 46,XY chromosome karyotype are reported. Both individuals were tall, with sparse axillary and pubic hair, and breasts were undeveloped in one and well developed in the other (she had some estrogen therapy). One had infantile but otherwise normal external genitals, while the other had poor development of labia majora and no clitoris. The vagina in each was normal, with a small cervix and uterus, and vaginal smears of the preadolescent type. Urinary 17-ketosteroids were normal, while gonadotropin levels were elevated. The gonadal streaks were extirpated, and histologic examination revealed the presence of fibrous stroma but no ova or follicles. Scattered clumps of Leydig cells and mesonephris remnants were found in one patient. Both patients responded well to cyclic hormonal therapy, i.e., menstrual withdrawal bleeding and breast development.