Autoantibodies against thyroid hormones and their influence on thyroxine determination with chemiluminescence immunoassay in dogs

作者：Piechotta Marion^*; Arndt Michael; Hoppen Hans Otto

来源：Journal of Veterinary Science, 2010, 11(3): 191-196.

DOI：10.4142/jvs.2010.11.3.191

• autoantibody
• autoimmune thyroiditis
• canine
• hypothyroidism
• lymphocytic thyroiditis

Autoantibodies against thyroxin (T4AA) and triiodothyronine (T3AA) are present in clogs with autoimmune thyroiditis and have been reported to interfere with immunoassays. The objectives of this study were to determine the frequency of autoantibodies and to determine whether interference occurs by T4AA, using a non-immunological method (high performance liquid chromatography, HPLC) for thyroxin (T4) measurement. Based on clinical symptoms, T4 and thyroid stimulating hormone (TSH) concentration, 1,339 clogs were divided into six groups: Group 1: hypothyroid (n = 149); Group 2: subclinicad thyroiditis (n = 110); Group 3: suspicious for non thyroidal illness (n = 691); Group 4: biochemical euthyroid (n = 138); Group 5: hypothyroid clogs under substitution therapy (n = 141); Group 6: healthy clogs (n = 110). The incidence of T4AA and T3AA, determined using radiometric assay, was low (0.5% and 3.8%) and higher in hypothyroid dogs compared to clogs suspicious for hypothyroidism (Group 2-4) (p < 0.05). T4AA was not detected in dogs with normal T4 and elevated TSH. T4 concentrations of T4AA positive samples determined using HPLC were comparable to results obtained by chemiluminescence immunoassay. These findings indicate that the probability of interference of T4AA leading to falsely elevated T4 concentration in the T4 assay seems to be low.

• 出版日期2010-9