Fine needle aspiration cytology and immunocytochemistry in tuberculosis thyroiditis - A case report

Background Tuberculosis of the thyroid is very rare and does not strike the clinician as a first clinical diagnosis of a thyroid nodule. To our knowledge, only 40 cases of tuberculous thyroiditis diagnosed by fine needle aspiration cytology (FNAC) are described in the English literature. Case We report a case of tuberculosis thyroiditis in a young woman who presented with a right-side solitary thyroid nodule of short duration (15 days), diagnosed by FNAC and confirmed by positive immunocytochemistry with monoclonal antibody to Mycobacterium tuberculosis complex. Ziehl Neelsen staining for acid-fast bacilli (AFB) was negative. Conclusion FNAC provides a confident preoperative diagnosis of thyroid tuberculosis, obviating the need for unnecessary surgical removal of thyroid nodule. Immunocytochemistry is an important diagnostic adjunct to FNAC in AFB-negative cases.