Pre-treatment and post-treatment parameters were compared using Wilxocon test. post-treatment measurements. Results:Anthropometric and laboratory parameters of the groups were not statistically different except for higher TSH levels in the SH group. Serum lipoprotein levels and dyslipidemia frequency were comparable between the groups. Compared to the controls, hypothyroidism symptom score was significantly higher in the SH group. Six months after euthyroidism was achieved, a significant reduction in the hypothyroid symptom score was Rabbit Polyclonal to HRH2 obtained in the SH group. Except for significantly higher serum TSH values, no significant differences regarding demographic characteristics, symptom scores and lipid parameters were present between patients with Hashimotos thyroiditis and the remaining SH patients. Conclusion:The results of this study showed that in children with SH i) the hypothyroidism symptom score was significantly higher than in euthyroid children, ii) LT4 treatment improved the hypothyroidism symptom score and iii) SH does not seem to be associated with dyslipidemia. Keywords:Subclinical hypothyroidism, children, dyslipidemia, LT4, hypothyroid symptom score == INTRODUCTION == Subclinical hypothyroidism (SH) is usually defined by elevated serum thyroid-stimulating hormone (TSH) and normal serum free thyroxine (fT4) levels (1). It occurs in 5-15% of the general population and the reported prevalence of SH in child years is usually GSK1016790A 1.7-5.7% (2,3,4,5). Although patients with SH appear to be asymptomatic and suffering solely from a biochemical abnormality, it is well recognized that some individuals may present with common symptoms and indicators of hypothyroidism as well as metabolic (dyslipidemia, insulin resistance, etc.), neuromuscular, neurobehavioral alterations (5,6,7,8,9,10) and cardiac dysfunction (6,7,11,12,13,14,15). Many previous studies that were conducted in adults with SH have reported variable lipid profile results (16,17,18,19). Any beneficial effect of L-thyroxine (LT4) replacement on lipid profile in subjects with SH is also controversial (7,19,20). Currently, limited data are available on lipid profile and symptom scores or around the possible effects of LT4 treatment in children with SH. With this study, we aimed i) to investigate whether SH is actually an asymptomatic laboratory diagnosis and ii) to explore the effects of SH and LT4 replacement on symptom scores and lipid profiles of children with SH. == METHODS == This prospective study was conducted on patients attending the outpatient pediatric endocrinology medical center of our institution. Twenty-seven children with SH (SH group) and 24 euthyroid healthy children (control group) of comparable age, pubertal status and sex were enrolled in the study. SH was diagnosed on the basis of elevated serum TSH levels and serum fT4 levels within the normal range. Hashimotos thyroiditis was diagnosed on the basis of the presence of either anti-thyroglobulin (anti-TG) or anti-thyroid peroxidase (antiTPO) antibodies (or both) in the serum (21). Only patients with stable elevated TSH and normal fT4 levels in at least two different measurements GSK1016790A 4-6 weeks apart were included in the study. Familial dyslipidemia, hepatic or renal dysfunction, diabetes mellitus, malignancy and obesity were excluded in both patients and the control group. In order to exclude any chronic disease, anemia or infection, we performed routine biochemical assessments [kidney and liver function assessments, Hitachi Modular Analytics (Roche, Tokyo, Japan)] and total blood count [blood samples (K3-ethylenediaminetetraacetic acid) analyzed in an automated hematology analysis system (LH-780, Beckman Coulter, Brea, CA, USA) with the impedance method]. The results were normal in all of the study participants and none of them were taking any kind of medication for the last 3 months. Blood samples for determination of fT4, TSH, anti-TG and anti-TPO antibodies, total cholesterol (TC), high-density lipoprotein (HDL)-C, low-density lipoprotein (LDL)-C and triglycerides (TG) were obtained simultaneously in the morning after an overnight fast. Height was measured using a Harpenden stadiometer with a sensitivity of 0.1 cm. Excess weight of the subjects was measured using a scale with a sensitivity of 0.1 kg (SECA, Hamburg, Germany), GSK1016790A with all their clothing GSK1016790A removed except undergarments. Body mass index (BMI) was calculated by dividing excess weight (kg) by height squared (m2). Pubertal development was evaluated according to Tanner staging (22). A testicular volume of 4 mL in males and stage 2-5 of breast development in females were considered to be consistent with puberty. Dyslipidemia was defined as lipid levels above the 95th percentile of healthy children (23). Two experienced radiologists performed thyroid ultrasound examinations in all patients with SH to identify the etiological factors (thyroid parenchymal echogenicity, thyroid hypoplasia, etc.). The volume of.