EVALUATION OF INFECTIOUS ETIOLOGY IN SUBACUTE THYROIDITIS - LACK OF ASSOCIATION WITH COXSACKIEVIRUS INFECTION

The etiology of subacute granulomatous thyroiditis (SAT) is obscure, a lthough it is postulated to be associated with viral infections and ge netic factors. In the present study the possibility of an infectious e tiology was prospectively studied in 27 consecutive patients with SAT. Special emphasis was put on the role of enteroviruses. Coupled sera ( interval one month) were taken from all patients and single sera from 29 control subjects for virus antibody determinations. Stool samples w ere collected for virus isolation and fine-needle aspiration samples f rom thyroid eland for the detection of enterovirus RNA using RT-PCR we re taken from SAT patients. Enteroviral antibodies were tested using t hree different methods: indirect ETA, heavy chain capture RIA, and sta ndard complement fixation (CF) test. Antibodies against other common v iral pathogens, including enteroviruses, were screened using the CF te st and those against Mycoplasma pneumoniae and Chlamydia pneumoniae us ing EIA and microimmunofluorescence techniques. respectively. Common r espiratory viruses were also screened from nasopharyngeal suction samp les by antigen detection EIA. Based on serological findings, one patie nt had acute Cytomegalovirus infection. All other patients were negati ve in antibody tests, virus isolation, RT-PCR, and antigen detection. Enterovirus RNA was not detected by PCR in the thyroid tissue in ally of the fine-needle aspiration samples. There was no evidence of recent enteroviral infections in SAT patients. The results suggest that SAT is not usually associated with acute infectious. No evidence was obtai ned to support the proposed role of enteroviruses as an important etio logic agent of SAT.