Detection of herpes virus DNA in post-operative thyroid tissue specimens of patients with autoimmune thyroid disease.

Aim: To demonstrate any differences in the detection of herpes simplex virus type 1 and 2, cytomegalovirus, human herpes virus type 6 and 7 DNA from thyroid tissue blocks of patients with autoimmune thyroid disease and multi-nodular goiter and to propose few mechanisms, which could explain the possible role of herpesvirus infection in the development of thyroid autoimmune responses. Material-methods: Thyroid tissue specimens were obtained postoperatively from 4 patients with multinodular goiter and 18 patients with autoimmune thyroid disease (Graves' disease and Hashimoto thyroiditis). Herpes virus DNA was detected using polymerase chain reaction based assays. Results: No statistically significant differences were observed between autoimmune thyroid disease and multinodular goiter tissue specimens concerning herpes simplex virus type 1, 2 DNA isolation (44.4% vs 0%, P= 0.094), human herpes virus type 6 DNA isolation (11.1 % vs 0%, P=0.48), human herpes virus type 7 DNA isolation (33.3% vs 25%, P=0.75). No CMV DNA was isolated from any tissue specimen. At least one kind of herpes virus DNA was detected in 13 out of18 (72.22%) AITD tissue specimens and in 1 out of 4 (25%) MNG tissue specimens (P=0.01). Conclusions: Although no data are available relating the direct effect of herpes infection on thyroid epithelial cells, a better understanding of how an aberrant immune response against the thyroid gland is initiated and propagated through herpes virus infection is required. Elucidation of the underlying mechanisms may allow the development of new etiologically based therapeutic modalities.