Paratracheal lymph nodes: a new sonographic finding in autoimmune thyroiditis.

PURPOSE: To assess the clinical value of paratracheal lymph nodes (PLNs) as a novel sonographic finding in autoimmune thyroiditis (AT).

METHODS

A total of 309 consecutive patients underwent sonographic examinations of the thyroid between 1998 and 2003. A single radiologist assessed the sonographic findings of AT and PLNs. All patients underwent serological tests for antimicrosomal antibodies (AMAs). Patients with clinical, cytological, or laboratory findings of thyroiditis formed the AT group with a positive AMA test (n = 199). Controls were patients with no signs of nodular thyroid disease, normal thyrotropin, negative AMA, and benign cytology (n = 110).

RESULTS

PLNs were seen in 184 of 199 patients in the AT group and in 28 of 110 controls (P < 0.001) (sensitivity of 93.4%, specificity of 74.5% in the diagnosis of AT). PLNs in controls were fewer (2.8 +/- 1.5 versus 4.7 +/- 2.6; P < 0.001) and smaller (8.2 +/- 2.4 mm versus 10.7 +/- 3.3 mm; P < 0.001) than in the AT group.

CONCLUSION

PLNs are often present in patients with AT and are detectable with sonography. Radiologists should be aware of the importance of including the paratracheal region in the evaluation of the thyroid gland.