Pituitary function in idiopathic haemochromatosis: hormonal study in 36 male patients.

Thirty-six male patients with idiopathic haemochromatosis were subjected to measurements of basal plasma values of testosterone, LH and FSH and to an LRH test. Nineteen were also subjected to basal plasma determinations of T3, T4, cortisol, TSH and prolactin and to a TRH test. In 11 cases GH values were measured before, during and after an arginine infusion. Seventeen patients were found to hae low levels of testosterone, LH and FSH, and no gonadotrophin responses to LRH. Seventeen others had normal levels of these three hormones, with normal responses to LRH. The two remaining patients had normal testosterone values but very increased gonadotrophin values: a fact which remains unexplained. Basal levels of prolactin, GH, T3, T4, and TSH were normal: cortisol levels were either normal or increased in cases of poorly controlled diabetes. Prolactin responses to TRH were always normal. TSH responses to TRH were impaired in 2 cases, and GH responses to arginine in 3 cases. Considering that other factors may be involved in the few impairments found in TSH and GH stimulations, it is concluded that the only indisputable pituitary insufficiency in about half of the cases of idiopathic haemochromatosis is gonadotrophic.