Diagnostic value of antithyroid peroxidase antibody for incidental autoimmune thyroiditis based on histopathologic results

Abstract

Detection of antithyroid peroxidase antibody (TPOAb) is widely used in the diagnosis of autoimmune thyroiditis (AIT), but no research has evaluated the diagnostic accuracy of TPOAb detection using histopathologic reference standards. To fill this research gap, this study assessed the diagnostic accuracy of detection of TPOAb and that of other serological markers in asymptomatic patients who had been diagnosed with AIT by histopathologic analysis after thyroid surgery. After review of patient records, 598 patients who had undergone thyroid nodule surgery were enrolled for examination for thyroid parenchyma by a pathologist and classification into no co-existing lymphocytic thyroiditis, Hashimoto thyroiditis, or non-Hashimoto type of lymphocytic thyroiditis (NHLT). The correlation between patient serological data and thyroid parenchyma pathology was analyzed. Statistically significant differences (P < 0.05) were found between co-existing lymphocytic thyroiditis and no co-existing lymphocytic thyroiditis groups regarding thyroid-stimulating hormone (TSH) and TPOAb levels. And, TPOAb titer was significantly associated with the degree of inflammation. An abnormal TPOAb titer was found in 86 of the 598 patients (14.4 %) and the specificity of TPOAb detection for AIT diagnosis was found to be 96.9 %. The prevalence of Hashimoto thyroiditis and NHLT in the 560 papillary thyroid cancer (PTC) patients was found to be 7.9 and 17.9 %, respectively. The results indicate that TPOAb titer is associated with the degree of thyroid inflammation and that detection of TPOAb is a very specific means of diagnosing AIT. The results also indicate that the incidence of AIT and PTC coexistence is relatively high.

Thyroid autoimmunity in patients with hyperprolactinemia: an observational study

“…Anti-TG and anti-TPO are indicators of thyroid inflammation and detection of these autoantibodies is a very specific means of diagnosing autoimmune thyroid disease (25,26). In this series of patients, among the individuals with autoantibody positivity TFTs abnormalities were more frequent in HPRL patients than in controls (60% vs. 9.1%, P < 0.001).…”

Evidence of impaired carbohydrate assimilation in euthyroid patients with Hashimoto’s thyroiditis

“…The histopathologic activity of the autoimmune process and TPO antibody titers have been described to correlate. 35 However, when all HT patients were stratified according to the respective levels of TPO and TG antibodies, there was no statistically significant difference between the subgroups of patients with antibody levels above and beneath 300 IU/ml. Consequently, there was no evidence that the high prevalence of FM among HT patients would have been caused directly by the autoimmune process Figure 2.…”

γδ Τ cells enhance B cells for antibody production in Hashimoto’s thyroiditis, and retinoic acid induces apoptosis of the γδ Τ cell

“…The diagnosis of HT was based on the clinical evaluation and the Japanese guidelines [20] by a combination of diffuses welling of the thyroid gland not due to any other condition (such as Graves' disease) and at least 1 of following laboratory findings: (1) a positive assay for TPO-Ab, (2) a positive assay for Tg-Ab, and/or (3) detection of lymphocytic infiltration in the thyroid gland confirmed by cytologic examination. Patients presenting with the histopathologic criteria of progressive loss of thyroid follicular cells, replacement of the gland by lymphocytes, and formation of germinal centers associated with fibrosis were diagnosed as HT [21,22]. The clinical evaluation included the patient's history, physical examination, and thyroid ultrasonography.…”