Endocrine Abstracts

Introduction: Autoimmune thyroiditis is a disease where the immune system attacks and destroys the thyroid gland. If the pathological exam lacks, the serum antithyroid antibodies are used to diagnose it. Also a useful tool is represented by the anterior cervical ultrasound.

Aim: Our aim was to study the ultrasound phenotype in patients diagnosed with Hashimoto’s thyroiditis (HT+).

Material and methods: The patients were investigated by anamnesis, serum analysis as thyroid stimulating hormone (TSH), antithyreoperoxidase antibodies (ATPO) and anterior cervical ultrasound. In order to perform the statistical analyses based on echographic aspects, 7 phenotypes were described. They refer to the echogenity, thyroid nodules and homogeneity. The patterns are 0 – no thyroid presented at the moment of investigation, 2 – hypoechogenic and pseudonodular, 3 – hypoechogenic and homogenous, 4 – hypoechogenic and micronodular (nodules <1 cm), 4 – macronodular (nodules >1 cm), 5 – hypoechogenic, inhomogenous and pseudonodular, 6 – anechogenic micronodular, 7 – diffuse hyperchogenic (normal).

Results: We studied 1500 patients. The sex ratio was 1483 women and 17 men. The HT+ group included 755 patients with levels of serum ATPO>34 IU/ml. The control group (HT-) included 745 patients with levels of ATPO<34 IU/ml. The mean age was 50.71 years in the first group and 55.19 years in the second group. For each pattern, the sensitivity, the sensibility and the positive predictive value were the following: pattern 0–0.46%, 99.36%, 50%, pattern 1–57.58, 93.07, 92.07%, pattern 2–13.41, 88.06, 61.09%, pattern 3–5.14, 87.29, 36.13%, pattern 4–8.17, 60.46, 22.42%, pattern 5–11.2, 93.97, 72.19%, pattern 6–0.64, 95.25, 15.91%, and pattern 7–3.4, 82.54, 21.39%.

Conclusion: Based on 93% specificity of the hypoechogenic pseudonodular phenotype, this pattern is highly suggestive for HT. The lowest chance of HT, based on our data, is if macronodules are described (specificity-60%). The hyperechogenic pattern with a PPV of 21% implies the fact that rarely HT is presented in a normal echographic thyroid.