The diagnosis and management of 22 patients with true hermaphroditism
are described. Sixteen of them were first seen before the age of 4 mon
ths. The initial manifestations were ambiguous genitalia in 20 cases (
two of them identified prenatally by ultrasound examination), isolated
clitoromegaly in one, and penile hypospadias plus unilateral cryptorc
hidism in one. All patients but one had at least one palpable gonad. E
leven of the twelve patients examined before the age of 6 months had b
asal plasma testosterone levels >0.4 ng/ml. In older patients the stim
ulation test was necessary to demonstrate male testosterone secretion.
The most common peripheral karyotype was 46,XX (17 cases); the other
karyotypes were 47,XXY (1 case) and mosaicism 46,XX/46,XY (2 cases) or
46,XX/47,XXY (2 cases). One of the patients with the 46,XX karyotype
had 46,XX/46,XY on fibroblast culture; four had the SRY gene in their
leukocytes and one in the tissue taken at gonadal biopsy. A vagina was
found in all patients at laparotomy, and a uterus was found in 17 cas
es (as a hemiuterus in 9). Genitography failed to demonstrate a uterus
in only one case. The testicular tissue was dysgenetic but the ovaria
n tissue was normal. Sex assignment was male in 8 patients (reoriented
by us in 2) and female in 14 patients (reoriented by us in 3). Sponta
neous pubertal development occurred in the 4 patients (2 boys, 2 girls
) with gondal tissue who reached pubertal age. We conclude that true h
ermaphroditism is a heterogeneous condition in terms of its genetic ba
ckground, with a prevalence of the 46,XX karyotype. There may be mosai
cism with a Y-bearing cell line limited to the gonad (its frequency is
probably underestimated), a paternal meiotic exchange between X and Y
occurring in 46,XX cases with SRY, or a lack of the SRY gene, suggest
ing that other genes working independently of SRY may also determine t
esticular differentiation.