The incidence of Hashimoto’s disease in nodular goitre: the concordance in serological and cytological findings

Summary Objective:  To determine the incidence of Hashimoto’s disease in nodular goitre and to ascertain the degree of the concordance between serological and cytological findings. Methods:  We retrospectively reviewed data from 188 patients who underwent a fine needle aspiration biopsy of the thyroid for uninodular or multinodular goitre with a documented serological level of antithyroid peroxidase (TPO) antibodies. AntiTPO antibodies were measured by immunochemiluminescent assay (Quest Diagnostics, Madison, NJ, USA). Results:  The study cohort consisted of 170 female and 18 male patients with a mean (± SD) age of 47.8 ± 14.9 years. AntiTPO antibodies were positive in 74 (39.36%) of the individuals and negative in 114 (60.63%). The cytodiagnoses were as follows: 5 (2.6%) cancerous, 18 (9.5%) suspicious, 12 (6.3%) inadequate, 92 (48.9%) benign and 61 (32.4%) consistent with chronic lymphocytic thyroiditis (CLT). For further analysis, we excluded all inadequate specimens. Based on the final sample of 176 patients, the sensitivity and specificity of antiTPO antibody test to detect CLT in nodular goitre were estimated to be 76.38% and 94.23% respectively. The prevalence of CLT in nodular goitre based on cytological criteria was (35.46%) compared with (31.97%) goitre based on positive antiTPO titres only. Conclusion:  There is a high degree of concordance between serological and cytological findings of CLT in people with nodular goitres. The high prevalence of CLT in nodular goitre justifies the use of antiTPO antibodies as part of the workup in this population.