2,3Pharmacological CO1686 agents that increase γ-globin production like Hydroxyurea (HU), as evidenced by an increase in HbF, have been considered as therapeutic agents for patients with β-thalassemia.4 Increasing the synthesis of fetal hemoglobin

can help reduce anemia and, thereby, improve the clinical condition of patients with β-TI.5 In several patients with β-TI and in patients with sickle-cell disease, a rise in total HbF level has been repeatedly reported during HU treatment. HU treatment can reduce blood transfusion dependency and even make some patients transfusion free, increasing their energy state and Inhibitors,research,lifescience,medical decreasing splenomegaly.6HU treatment is protective for hypothyroidism, pulmonary hypertension, extramedullary hematopoiesis, leg ulcers, and osteoporosis.7 The commonest side effects of HU therapy include neutropenia Inhibitors,research,lifescience,medical and thrombocytopenia, both of which are predictable and

easily manageable.8 In the few studies conducted on the side effects of HU in β-TI patients, dermatological, neurological, and gastrointestinal Inhibitors,research,lifescience,medical adverse effects were seen without any reports of endocrine abnormality, bone marrow suppression, or hematological toxicity.9In the present study, medium to long-term follow-up of chronic low-dose HU was inspected to analyze the effect of HU treatment on the thyroid function of patients with β-TI. Patients and Methods This cross-sectional study was done during 2010 in southern Iran. Considering α=0.05, power=70%, and estimated 10% Inhibitors,research,lifescience,medical difference of ratio between the two groups, the sample size was calculated as 88 patients by Power SSC software. However, due to financial constraints, we enrolled only 75 patients with β-TI as our case group to be treated with HU. These patients were selected via a simple random sampling method. Diagnosis of β-TI was based on hemoglobin electrophoresis and complete blood count. All the patients were under routine follow-up by an expert hematologist

and Inhibitors,research,lifescience,medical were blood transfusion independent. Patients with mean serum ferritin level<1000 ng/dl in the recent 5 years, age≥11 years, and HU consumption with a dose of 8-15 mg/kg/day for at least 5 years were included in this study. The control group consisted of 31 patients with β-TI without using HU, ferritin level of <1000 ng/ml Edoxaban (in order to exclude iron overload as a confounding factor) in the recent 5 years, and age≥11 years. The two groups were matched for age and sex. Patients with no desire to participate in the project, ferritin level of >1000 ng/dL in the recent 5 years, or age<11 years were excluded from the study. All the patients were referred for paraclinical evaluation, including the serum levels of ferritin, T4, and thyroid stimulating hormone (TSH). Finally, a proficient pediatric endocrinologist reviewed the hormonal profile of the patients to find patients affected by hypothyroidism. The diagnosis of hypothyroidism was based on T4<40 nmol/L and TSH>3.5 µIU/ml.