Hypothalamic pituitary adrenal function in patients with thalassemia major

We examined the adrenocortical function in 14 italian thalassemic patients (8 f., 6 m.) aged 12 to 28. The following hormones were determined in each subject: plasma cortisol and aldosterone levels in both basal conditions and after maximal and submaximal stimulus (250 and 5 micrograms respectively) with synthetic corticotrophin beta 1-24 (Synacthen Ciba); corticotrophin and cortisol response to insulin-induced hypoglycaemia (0.15 U/kg iv.). Tests were repeated in all patients four years later. Normal controls were a group of 10 normal subjects matched for age, sex and body mass. Normal basal values of cortisol, aldosterone and ACTH were observed. Impaired cortisol response after stimulation with 5 micrograms of ACTH (6 patients) and after hypoglycaemia (4 patients) was identified. At the second test, four years later, one patient showed impaired cortisol response to both ACTH (5, micrograms) and hypoglycaemia, unlike the normal response to the first test. In all the others the cortisol response to stimulation did not differ from previous ones. In conclusion reduced ACTH and cortisol reserves detected in some thalassemic patients may be related to iron infiltration in the pituitary and adrenal glands. However, the present study did not indicate any significant correlation between either total blood load or serum ferritin and adrenal function parameters. Alteration in circulating hormones catabolism and impaired synthesis of transport proteins caused by chronic liver disease made adrenocortical hypofunction an even more complex picture to understand.