Correlation of Fine Needle Aspiration Cytology Findings with Thyroid Function Test in Cases of Lymphocytic Thyroiditis

Background. Chronic lymphocytic thyroiditis is the second most common thyroid lesion diagnosed on FNAC after goiter. FNAC is reliable tool in the diagnosis of thyroid lesion. Objective. To correlate FNAC cytologic findings with TFT in the lymphocytic thyroiditis. Methods. 175 patients with thyroid swellings were referred for FNAC as well as TFT during 2011-2013. Fine needle aspiration cytology was performed using non-aspiration or aspiration techniques and TFT performed on Beckman culter access 2. Results. Lymphoid infiltrate was seen in 55 cases. The commonest age group of lymphocytic thyroiditis was 21-30 years with male : female ratio being 1 : 10. Anti-TPO and TSH were elevated in 96.16% (25/26) of cases with grade 3 lymphoid infiltrate, 94.12% (16/17) of cases with grade 2, and 91.67% (11/12) of cases with 1 grade. Increased anti-TPO with raised TSH without any lymphoid infiltrate was seen in 5 cases and 5 cases showed only raised TSH without raised anti-TPO and without any lymphoid infiltrate. We observed that grade 3 lymphocytic infiltration has correlation with anti-TPO and TSH together or TSH alone but not with anti-TPO alone. We also observed that anti-TPO and TSH together are significant even if no lymphocytic infiltration is present. Conclusion. Grade 3 lymphocytic infiltration has statistical correlation with anti-TPO and TSH together or TSH alone but not with anti-TPO alone. Anti TPO was adjunct to TSH in grade 3. The presence of Hurthle cell change, giant cells, and granulomas has no statistical correlation with lymphocytic thyroiditis.