Endocrinopathy in thalassaemia major.

Area of Science:

• Endocrinology
• Hematology

Background:

• Thalassaemia major is a severe genetic blood disorder.
• Endocrine dysfunction is a known complication of thalassaemia major, often attributed to iron overload.

Purpose of the Study:

• To investigate pituitary, adrenal, and pancreatic functions in patients with thalassaemia major.
• To explore the relationship between endocrine impairment and iron deposition in endocrine organs.

Main Methods:

• Assessed pituitary, adrenal, and pancreatic function in 9 thalassaemia major patients.
• Measured 9 a.m. plasma ACTH, cortisol, and growth hormone response to insulin-induced hypoglycemia.
• Evaluated 24-hour urinary 17-ketosteroids and 17-hydroxycorticosteroids.
• Performed physiological adrenal stimulation tests with tetracosactrin.
• Conducted oral and intravenous glucose tolerance tests, measuring plasma glucose and insulin response.

Main Results:

• Elevated 9 a.m. plasma ACTH (148-480 pg/ml) compared to normal (15-70 pg/ml).
• Normal cortisol and growth hormone response to hypoglycemia; normal urinary steroid excretion.
• Subnormal adrenal response to physiological tetracosactrin stimulation.
• Impaired glucose tolerance in 4 patients; significantly reduced plasma glucose utilization (Kg) and insulin response.

Conclusions:

• Patients with thalassaemia major exhibit widespread endocrine dysfunction, particularly affecting the adrenal cortex and pancreas.
• Elevated ACTH suggests pituitary hyperfunction secondary to adrenal unresponsiveness, potentially caused by iron deposition.
• Physiological adrenal stimulation tests are crucial for detecting early-stage adrenal cortex dysfunction.