Comparison of the sonography index of thyroid gland with serum level of Anti-thyroid peroxidase, Anti-thyroglobulin and thyroid function test in patients with Hashimoto thyroiditis

Abstract

Background The purpose of this study was to determine the association of sonographic parameters with the serum levels of anti-thyroid peroxidase (TPO), anti-thyroglobulin (Tg), and thyroid hormones in patients with Hashimoto's thyroiditis. Methods 149 patients (118 females, 31 males; aged 18–60 years; mean age: 38.60 ± 8.03 years) who were diagnosed with Hashimoto's thyroiditis were enrolled in the study. Blood sample was taken to measure the serum levels of free T3 and T4, thyroid stimulating hormone (TSH), anti-TPO antibody titers, and anti-Tg antibody titers. The thyroid sonography of each patient was classified into one of the five grades by real-time ultrasonography (US) based on echogenicity, thyroid size, and thyroid pattern. We evaluated whether a correlation existed between thyroid characteristics on US and serum levels of thyroid hormones, anti-TPO and anti-Tg. Results Nodular structures were detected in 54 (36.2%) patients (38 micronodular and 16 macros nodular). Echogenicity was recorded as isoechoic in 15 (10.07%) and hypoechoic in 119 (79.87%) subjects. Euthyroid ‎subjects had significantly thicker isthmus than overt and subclinical hypothyroid patients (p = 0.018). Mean serum TSH, anti-Tg and anti-TPO titers was significantly higher in patients with micronodules than those with micronodules and subjects without nodules (P < 0.05). Isthmus thickness had a significant negative correlation with FT4 and FT3 (P = 0.046; r = 0.11& P = 0.017; r = 0.15, respectively). Thyroid autoantibodies had positive significant correlations with different parameters of the thyroid volume (P < 0.05). Conclusions Thyroid’s US findings in addition to serum levels of anti-Tg and anti-TPO titers would be useful in diagnosis and evaluation of the severity and extent of Hashimoto's thyroiditis, but further evaluations are needed. Trial registration: Trial registry identifier IR.SUMS.REC.1395.S161 (2015/11/30).