[Osteodystrophy in thalassemia major]. / Osteodistrofia nella talassemia major.

Subjects with thalassemia major frequently have bone disorders of debatable pathogenesis. We attempt here to analyze the relationships between siderosis and thalassemic osteodystrophy by assessing calcium-phosphorus balance, hormone-vitamin homeostasis, osteoblastic-osteoclastic activity parameters, and bone mineral density (BMD) in 30 patients with thalassemia major (16 males, 14 females, age range 17-30 years). We found a significant increase in ferritin (p < 0.001) and significant decreases in serum i-PTH, 25OHD3, 1.25(OH)2D3, osteocalcin, estradiol, testosterone and FT4 (p < 0.001) in both sexes. In all patients a net decrease of bone mineral density was documented (p < 0.001). These results were then submitted to linear regression analysis: positive correlations between BMD and FT3, testosterone, estradiol (p < 0.01), were documented, and an inverse correlation between osteocalcin and ferritin was confirmed. Our findings suggest that thalassemic osteodystrophy is the result of several inhibitory influences on osteoblastic activity and bone apposition (related to hormone deficits and siderosis) which are aggravated further by anemia, chronic hypoxia and red marrow expansion.

An association of primary hyperparathyroidism and non medullary thyroid carcinoma.

A 40-year-old woman was admitted because of long-lasting asymptomatic hypercalcaemia. About 2 years earlier she underwent thyroidectomy and further 131 I therapy because of well-differentiated non medullary thyroid carcinoma. On admission biochemical data and hormonal values (serum calcium, serum phosphorus, i-PTH) were consistent with primary hyperparathyroidism; ultrasonography, computed tomography, thallium-technetium scintiscanning disclosed right paratracheal mass; on surgical procedure a right parathyroid adenoma was removed. The coexistence of non medullary thyroid carcinoma and primary hyperparathyroidism is rare: the prior 131 I therapy might be linked to subsequent development of parathyroid adenoma.

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.