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    Evaluation of the Glucocorticoid, Mineralocorticoid, and Adrenal Androgen Secretion Dynamics in A Large Cohort of Patients Aged 6-18 Years with Transfusion-dependent ?-Thalassemia Major, with an Emphasis on the Impact of Cardiac Iron Load
    (Karger, 2016) Ucar, Ahmet; Oner, Nergiz; Ozek, Gulcihan; Cetincakmak, Mehmet Guli; Abuhandan, Mahmut; Yildirim, Ali; Kaya, Cemil
    [Abstract Not Available]
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    Öğe
    Evaluation of the glucocorticoid, mineralocorticoid, and adrenal androgen secretion dynamics in a large cohort of patients aged 6-18 years with transfusion-dependent ?-thalassemia major, with an emphasis on the impact of cardiac iron load
    (Springer, 2016) Ucar, Ahmet; Oner, Nergiz; Ozek, Gulcihan; Cetincakmak, Mehmet Guli; Abuhandan, Mahmut; Yildirim, Ali; Kaya, Cemil
    The variable presence of adrenal insufficiency (AI) due to hypocortisolemia (HC) in patients with thalassemia is well established; however, the prevalence of adrenocortical hypofunction (ACH) in the zona glomerulosa and zona reticularis of the adrenal cortex is unknown. To establish the prevalence of ACH, we examined the cortisol response to 1-A mu g and 250-A mu g ACTH tests, plasma aldosterone (A)/plasma renin activity (PRA) ratio, and serum dehydroepiandrosterone sulfate (DHEAS) levels in a large cohort of patients with thalassemia, and to investigate the impact of total body iron load (TBIL) on adrenocortical function. The setting used was University hospital and government-based tertiary care center. One hundred twenty-one (52 females) patients with beta-thalassemia major (beta-TM) and 72 healthy peers (38 females) were enrolled. The patients underwent a 250-A mu g cosyntropin test if their peak cortisol was < 500 nmol/L in a 1-A mu g cosyntropin test. Magnetic resonance imaging (MRI) was performed to assess the MRI-based liver iron content and cardiac MRI T2* iron. The associations between ACH and TBIL were investigated. The patients with thalassemia had lower ACTH, cortisol, DHEAS, and A/PRA values compared with the controls (p < 0.001). Thirty-nine patients (32.2 %) had HC [primary (n = 1), central (n = 36), combined (n = 2)], and 47 (38.8 %) patients had reduced DHEAS levels; 29 (24.0 %) patients had reduced A/PRA ratios. Forty-six (38.0 %) patients had hypofunction in one of the adrenal zones, 26 (21.5 %) had hypofunction in two adrenal zones, and 9 (7.4 %) had hypofunction in all three zones. Patient age and TBIL surrogates were significant independent parameters associated with ACH. Cardiac MRI T2* iron was the only significant parameter that predicted the severity of ACH at a cut-off of 20.6 ms, with 81 % sensitivity and 78 % specificity. Patients with thalassemia have a high prevalence of AI due to HC and zona glomerulosa and zona reticularis hypofunction. TBIL surrogates can predict ACH, but cardiac iron was the only surrogate that was adequately sensitive to predict the severity of ACH.
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    Öğe
    MRI-based evaluation of the factors leading to pituitary iron overload in patients with thalassemia major
    (Masson Editeur, 2016) Cetincakmak, Mehmet Guli; Hattapoglu, Salih; Menzilcioglu, Sait; Alan, Bircan; Uluca, Unal; Ucar, Ahmet; Soker, Murat
    Aim: Given the lack of studies evaluating pituitary iron overload in patients with thalassemia major, we used magnetic resonance imaging (MRI) to evaluate these patients and the factors affecting the disease process. Materials and methods: The 84 patients with beta-thalassemia major who were included in this study were referred to our clinic for cardiac and hepatic T2* MRI. T2*-weighted images of the pituitary gland, heart, and liver were obtained using a 1.5-tesla MRI unit and a multi-echo gradient-echo sequence. Associations between pituitary T2*, cardiac T2*, hepatic T2*, pituitary height, serum ferritin (SF) level, patient age, and other demographic findings were assessed. Results: Pituitary T2* values correlated with hepatic TZ values, cardiac T2* values, SF level, and patient age (P <= 0.001, 0.001, 0.001, 0.01, respectively) but not with pituitary height (P=0.76). Pituitary and cardiac T2* values were lower in the subset of patients who underwent splenectomy (P=0.046 and P= 0.002, respectively). Conclusion: Pituitary iron overload rapidly increases during puberty and in this study correlated with cardiac and hepatic T2* values, patient age, SF level, and liver size, but not with the height of the pituitary. Pituitary iron overload also increases following splenectomy. Together, these findings indicate that numerous factors contribute to pituitary iron overload. (C) 2016 Elsevier Masson SAS. All rights reserved.