High Prevalence of Common Human Viruses in Thyroid Tissue.
Level 4 - case-series / case-control
Case-control study evaluating viral presence in thyroid tissue from autoimmune thyroid disease patients and non-autoimmune controls.
PubMed 35909527 · doi:10.3389/fendo.2022.938633
What was done
Investigators evaluated the presence of ten human viruses in thyroid tissue obtained via core needle biopsy or surgery from 35 patients with autoimmune thyroid disease (20 with Graves' disease and 15 with Hashimoto's thyroiditis) and 18 controls undergoing neck surgery for non-autoimmune conditions. Enteroviruses and human herpesvirus 6 were enriched in cell cultures and detected using PCR and immunofluorescence, while the remaining viruses were tested directly by PCR on tissue samples.
What was found
An infectious virus was detected in 40 of 53 total cases (75%). Overall, 43% of cases harbored a single virus and 32% had coinfections with two or more virus types. Specific detection rates across all 53 samples were: enterovirus in 27/53 (51%), human herpesvirus 6 in 16/53 (30%), parvovirus B19 in 12/53 (22%), Epstein-Barr virus and cytomegalovirus in a few cases only, and one gastroenteric virus group in a single specimen. Viral distribution was not statistically different between autoimmune thyroid disease cases and controls.
Why it matters
The findings demonstrate that common human viruses frequently reside in thyroid tissue, showing that viral presence alone does not distinguish autoimmune thyroid disease from non-autoimmune controls.
Limits
The study had a small sample size of 53 participants (35 cases and 18 controls). The cross-sectional design cannot establish whether the detected viruses represent causal triggers, cofactors, or harmless bystander infections.
Cited by
- contradicts Epstein-Barr virus is a major precursor to Hashimoto's thyroiditis.