Primary thyroid tuberculosis associated with thyroid dysfunction in a Child: An unexpected diagnosis

Primary thyroid tuberculosis is a rare form of extra-pulmonary tuberculosis, with only a few cases recorded in the literature, and none of which had thyroid dysfunction. A 6-year-old child came to us with complains of fever and neck swelling for one month. A neck examination indicated a widespread enlargement in the thyroid region, which was more noticeable on the left side. Thyroid function tests indicated elevated TSH (thyroid stimulating hormone) and low T3, T4, indicating hypothyroidism. Contrast-enhanced computed CT revealed enlarged thyroid glands with a collection inside the left lobe. Cytology of the aspirate revealed epithelioid cell granulomas and a few lymphocytes against a background of extensive caseous necrosis. The Cartridge-Based Nucleic Acid Amplification Test detected Mycobacterium tuberculosis. No tubercular infection was discovered in the lungs or any other body organ. A diagnosis of primary thyroid tuberculosis associated with hypothyroidism was made, for which he received levothyroxine and antitubercular therapy.