Endocrine Abstracts

Introduction: Diagnosis of autoimmune thyroiditis is made by determination of elevated antibodies against thyroid peroxidase and thyroglobulin, and a hypoechoic pattern in ultrasound. In the present study we have performed a grey-scale quantitative analysis of thyroid echogenicity in the patients affected by autoimmune thyroiditis, obtaining the degree of hypoechogenicity associated with the appearance of thyroid dysfunction.

Material and methods: Six hundred and thirty-two patients who had autoimmune thyroiditis proven clinically, by laboratory and ultrasonographically were included in our study. Serum thyrotropin (TSH), thyroid hormones (fT3, fT4) and thyroid autoantibodies (Anti TPO Ab, Anti Tg Ab) were evaluated. Thyroid ultrasonography was performed in all subjects. An experienced endocrinologist who was uninformed about the laboratory results performed thyroid ultrasonography.

Results: Five hundred and fifty-one (%87.2) of 632 patients were female and 81 (%12.8) were male. Mean age of the female and male patients were 46.2±0.5 and 48.6±1.71 years respectively. The thyroid parenchyma was classified as minimal heterogeneous, heterogeneous, and severe heterogeneous. TSH, Anti TPO Ab, and Anti Tg Ab levels were compared between these groups. TSH levels in the minimal heterogeneous and heterogeneous groups were significantly lower than the severe heterogeneous group (P<0.01 and P<0.001 respectively). When Anti TPO levels were compared significant difference was detected between groups (P<0.001). Anti TPO levels were lowest in the minimal heterogeneous, and highest in the severe heterogeneous group. In addition, Anti Tg levels were lower in the minimal heterogeneous and heterogeneous groups when compared with the severe heterogeneous group (P<0.001 and P<0.001 respectively). As with Anti TPO, Anti Tg levels were lowest in the minimal heterogeneous, and highest in the severe heterogeneous group.

Conclusion: Our study has shown that the paranchymal destruction has strongly associated with thyroid antibodies and TSH levels when it is classified by grey-scale ultrasonography.