The study or the influence of different iodine intakes on tumor necrosis factor-alpha and thyroid autoantibody in patients with hashlmoto thyroiditis

Abstract

Objective To study the relationship between cellular immunity in vivo,humoral immunity and different iodine intakes in patients with hashimoto thyroiditis(HT).Methods Seventy-six HT patients were divided into two groups acconding to the median of urine iodine (MUI =491.20 μ g/L):HT I group (urine iodine≥MUI) with 37 cases and HT Ⅱ group (urine iodine ＜ MUI) with 39 cases.And 49healthy persons were selected as control group.The level of free three triiodothyronine (FT3),free thyroxine (FT4),thyroid stimulating hormone (TSH),thyroglobulin antibody (TGAb),thyroid peroxidase antibody (TPOAb),thyroid hormone receptor antibody ( TRAb ),tumor necrosis factor-alpha ( TNF- α )of all groups were detected.Results The levels of FT3 and FT4 in HT I group [ (2.67 ± 1.93 ),( 4.22 ± 3.77) pmol/L ]and HT Ⅱ group [ ( 3.19 ± 1.63 ),( 5.99 ± 3.97 ) pmol/L ] were significantly lower than those in control group [(5.30± 1.10),(16.50 ±2.70) pmol/L] (P ＜ 0.01).The levels of TNF-α in HT I group [(6.14 ± 1.83)ng/L] and HT Ⅱ group [ (6.09 ± 1.50) ng/L] were both obviously higher than that in control group [ ( 1.90 ±0.60) ng/L] (P ＜ 0.01 ).The levels of FT3 and FT4 were lower and TNF α was higher in HT I group than those in HT Ⅱ group,but there was no statistically significance (P ＞ 0.05 ).The positive rate of TPOAb,TGAb in HT I group [97.3％(36/37),81.1％(30/37)] and HT Ⅱ group [89.7％(35/39),74.4％(29/39)]were significantly higher than those in contnol group [ 18.4％(9/49),12.2％(6/49 ) ] (P ＜ 0.01 ).There was no statistically difference of the positive rate of TPOAb,TGAb and TRAb between HT I group and HT Ⅱ group (P ＞ 0.05).While the percentage of patients with high titer of TPOAb and TGAb in HT I group was higher than that in HT [Ⅱ group,and there was statistical difference(P ＜ 0.05 ).The level of TRAb in HT I group was higher than that in HT Ⅱ group [ ( 1.25 ± 0.14) mU/L vs.( 1.16 ± 0.21 ) mU/L ],but there was no significant difference (P ＞ 0.05).Correlated anlysis showed that FT3 was negatively correlated with TGAb and TPOAb (r =0.342,-0.397,P ＜0.05),and TNF-αwas positively correhted with TGAb and TPOAb (r =0.405,0.561,P ＜ 0.05).Conclusions High iodine intake influences the autoimmune mechanism of HT patients.The iodine intake should be limited in HT patients. Key words: Thyroiditis,autoimmune; Tumor necrosis factor-alpha; Thyroid hormones; Autoantibodies