Endocrine Abstracts

Anti-thyroperoxidase autoantibodies (TPOAb) are one of the major secondary autoantibodies associated with AITD. Many endocrine hospital referrals are received for patients with elevated TPOAb levels without other disordered thyroid function tests.

This study aimed to investigate the use of TPOAb testing in hospital practice, to determine whether the presence or absence of TPOAb indicates the existence of thyroid disease and the effect of the TPOAb result on patient management.

A case-controlled retrospective study was conducted. Data regarding anti-thyroperoxidase autoantibody assay results performed during a six month period at Chelsea and Westminster Hospital's Immunology Laboratory was obtained. 108 positive result cases were selected (TPOAb greater than or equal to 150 international units per millilitre) and age and sex matched with corresponding negative controls (TPOAb less than 150 international units per millilitre). Free thyroxine and thyroid stimulating hormone levels were sought from the hospital's result database. Health records were scrutinized for information regarding signs and symptoms of thyroid disease, past and family histories of thyroid and autoimmune disorders, commencement on drug treatment following the TPOAb test as well as the requesting department and qualitative data regarding patient follow up. Scores were assigned to represent the perceived use of the test, the degree of follow up and the test result's influence on patient management. The data was analysed using SPSS version 11.5 for Windows.

No change in management was found to be dependent on the TPOAb result. TSH level was significantly higher in the TPO positive group than in the TPO negative group (2-tailed sig = 0.006), and higher in females compared with males. Positive correlations were demonstrated (2-tailed sig less than 0.05) between TPOAb result and TSH level in females and TSH level in euthyroid females.

TPOAb testing in hospital practice should be abolished as patient management has been shown to be independent of the test result.