[Primary amenorrhea and XY karyotype: identifying patients in risk].

PURPOSE to verify the prevalence and clinical characteristics of patients with primary amenorrhea and XY karyotype, evaluated in our Service, aiming at identifying findings which could help their recognition. METHODS from January 1975 to November 2007, 104 patients with amenorrhea were evaluated. All the cases were analyzed by the karyotype by GTG bands. Among them, 21 (20.2%) presented a XY 46 constitution. Nevertheless, two of them were excluded from the study, because of incomplete data in their patient's chart. Most of the 19 patients who formed the sample had been referred to us by the gynecology clinics (63.2%). Their ages varied from 16 to 41 years old (an average of 22.1). Data were collected about their family and previous history, physical examination and results of complementary exams and the information was taken into consideration to determine the diagnosis. RESULTS the predominant diagnosis was resistance to androgens syndrome (n=12; 63.2%); five patients (25.3%) presented XY pure gonadal dysgenesis (XY PGD), one (5.3%) 17 alpha-hydroxylase deficiency, and one (5.3%), 5 alpha-reductase deficiency. Clinical findings frequently found in these patients included abnormal development of secondary sexual characters (n=19), uterine agenesia with a blind vagina (n=14), family history of amenorrhea (n=8), and palpable gonads in the inguinal canal (n=5). Two of them presented a history of inguinal hernia. Systemic arterial hypertension was only diagnosed in the patient with 17 alpha-hydroxylase deficiency, and gonadal malignization, in the one with XY PGD. CONCLUSIONS the rate of patients with XY karyotype (20%) was higher than the one described in the literature (3 to 11%). It is believed that this fact is related to the way patients are usually referred to our service. Some findings from the clinical history and from the physical examination should be evaluated as a routine in individuals with primary amenorrhea. This way, there would be a more precocious detection of XY 46 patients, and a better clinical management of them, as a consequence.