clinical and paraclinical aspects of thyroid tuberculosis

the common midline neck masses include thyroglossal duct cyst, lipomas, thyroid tumor or cyst and rarely a midline lymph node, particularly the node just above the thyroid isthmus. thyroid tuberculosis (ttb) is a rare cause of thyroid disease and therefore only occasionally included in the differential diagnosis. in this study we tried to explain the clinical and paraclinical manifestations of ttb with a case series of 26 patients with definite or suspicious diagnosis of ttb. there were 7 cases with definite tuberculosis involvement of thyroid and 19 cases which were suspicious to have ttb. in fine needle aspiration cytology (fnac) of 4 definite patients, acid fast bacillus was seen (57.1%). ppd skin test was positive only in 3 patients with definite ttb (42.9%). microscopically, epithelioid granuloma, langerhans giant cell and evidences of carcinoma, each was shown in one separate case. it is therefore important to note that tuberculosis should be considered in the differential diagnosis of anterior cervical swellings. fnac can help in confirming the diagnosis but final confirmation is made by histopathological and biochemical examination; and patients respond well to surgery with antituberculous drugs.