Diagnostic usefulness of fragments of crushed cells in autoimmune thyroiditis.

Fine-needle aspiration cytology has emerged as an important diagnostic tool in cases of autoimmune thyroiditis. However, the patchy nature of this disease and its coexistence with other thyroid pathologies, with only subtle demonstrable cytologic features in many cases can lead to misdiagnosis. Of 313 thyroid aspirates, 62 were diagnosed as autoimmune thyroiditis. Fragments of crushed cells were observed in 51 (82.11%) of autoimmune thyroiditis (P < 0.001). The presence of "crush artifact" that can be easily picked up on low magnification should be used as an important criterion for the diagnosis of thyroiditis. It is particularly helpful in cellular smears from thyroiditis to avoid misdiagnosis of neoplasia.