Spectrum of adrenal dysfunction in HbE/Beta thalassemia.

BACKGROUND: Adrenal insufficiency (AI) in HbE/Beta thalassemia, including evaluation of mineralocorticoid axis had not been studied.

AIMS AND OBJECTIVES: In this study we attempted to evaluate the prevalence of AI in HbE/Beta thalassemia and wanted to determine if the prevalence of AI varied according to severity of HbE/Beta thalassemia and transfusion requirements.

METHODS: In this observational, cross-sectional study, one hundred four patients with HbE/Beta thalassemia were evaluated. Amongst them 57 and 47 were transfusion dependent (TD) and non-transfusion dependent (NTD). According to Mahidol criteria, patients were classified into mild (n=39), moderate (n=39) and severe (n=26) disease. Early morning (8 AM) serum cortisol, plasma ACTH and plasma aldosterone, renin were measured. Patients with baseline cortisol of 5-18 μg/dl underwent both 1μg and 250 μg SST (Short Synacthen Test). According to these results patients were classified as having either normal, subclinical, overt (primary/secondary) adrenal dysfunction.

RESULTS: Adrenal insufficiency was found in 41% (n= 43). Amongst them 72% (n= 31) had primary AI and 27% (n= 12) had secondary AI.Thirty threepatients (31%) with normal or elevated ACTH, with low or normal aldosterone with high renin were diagnosed as subclinical adrenal insufficiency. There was no difference in prevalence of AI between TD and NTD (p = 0.56) nor was there was any difference in prevalence of AI according to disease severity (p=0.52).

CONCLUSION: Adrenal insufficiency is common in HbE/Beta thalassemia and is independent of transfusion dependency and disease severity.