Endocrine Abstracts

Introduction: The prevalence of autoimmune disorders (AID) is more frequent in patients with Hashimoto’s thyroiditis (HT).

Aim: To see if the clinical and biochemical aspects are different among the patients with HT and if they change related to the systemic or organ specific AID.

Material and method: A. HT was diagnosed on antithyroperoxidase antibodies (ATPO) over 34 UI/ml. B. 491 patients with HT were investigated; 67 (15.8%) of them associated other known AID. C. AID were also searched in 404 patients with ATPO less than 34UI/ml, as control group; 21 (5.19%) of them had at least one AID. D. TSH, antithyreoglobulin antibodies (ATG) and the thyroid echographic pattern – spilt into 7 subtypes, according to our original classification, were also investigated. E. Statistical analysis was performed using student’ t test and χ² test, as appropriately.

Results: 1. Prevalence of AID in HT patients is higher than in control group (P<0.001, χ²=17.82, 56 degrees of freedom). 2. The most frequent AID were vitiligo, immune hepatitis, rheumatoid arthritis, drugs allergies and premature ovarian failure. 3. The mean age at diagnosis was not statistically different between patients with HT and AID and patients with HT, but without AID, respectively 50.97 years vs. 50.06 years, P=0.6. 4. The sex ratio in HT-AID patients and HT-nonAID patients was the same (96% women). 5. Average of ATPO levels in HT-AID patients was statistically significant higher than in HT-nonAID patients (respectively 964.47 UI/ml vs. 587.44 UI/ml, P=0.054). 6. The mean values of TSH were not different between the two subgroups (8.81 μUI/ml vs. 9.76 μUI/ml, P=0.75). 7. The difference between mean ATG levels was small and non significant (P=0.34). 8. There was a certain difference between echographic patterns (P=0.025, χ²=16.06, 7 degrees of freedom), but without the predominance of a specific subtype.

Conclusions: 1. In HT, AID are more frequent than in control group. 2. Vitiligo is by far the most frequently AID associated with HT. 3. Higher ATPO levels are found in patients with HT associated with other AID.