Evaluation of SHBG test for disclosure of insensitivity to androgens

A laboratory test enabling to reveal and confirm the suspicion on the insensitivity to androgens was evaluated. The test consisted of determination of the decline in plasma level of sex hormone binding globulin (SHBG) on the 7th day after administration of a single dose of testosterone preparation (Testoviron Depot 100, Schering, 2 mg/kg body weight). The upper limit of percentual SHBG decline, below which the patients can be considered normal responders (i.e. subjects without insensitivity to androgens), obtained from the follow up of the time course of SHBG changes after Testoviron application to 6 healthy men, was established as 83.6%. The level of percentual SHBG decline, above which the patients were considered non-responders with impaired peripheral sensitivity to androgens was assessed from the imprecision of immunoradiometric determination of SHBG and amounted 91.9%. The test was used and evaluated in 26 patients with 46 XY karyotype, representing various cases of intersex, gonadal dysgenesis and male hypogonadism, out of which four subjects with clinically confirmed impaired peripheral sensitivity to androgens were discovered. The test however, appeared not to be reliable in cases of very low basal SHBG levels, i.e. below 15 nmol/l.