Testicular adrenal rest tumours in salt wasting congenital adrenal hyperplasia (in vivo and in vitro studies).

We describe the case of a 20-year-old patient with salt-wasting congenital adrenal hyperplasia (CAH) related to 21-hydroxylase deficiency. Bilateral craggy testicular tumours were found, requiring histological evaluation. Prior to the surgical procedure, the patient was treated with dexamethasone (he presented cortisol deficiency) and was stimulated with ACTH. High levels of 11beta-OH steroids measured in the gonadal vein, compared with peripheral blood samples suggested the presence of adrenal rests. Incubation of the tumours (which could not be differentiated histologically, from Leydig tissue), with radioactive steroid precursors was carried out. The results revealed the testicular tumours were of adrenal tissue origin, associated with 21-hydroxylase deficiency. The patient's non-compliance to glucocorticoid treatment was the main cause of his hypogonadotropic hypogonadism.