Primary Isoniazid Mono-Resistant Extrapulmonary Tuberculosis Presenting as Cervical Lymphadenitis: The World's First Case of Its Type.

Tuberculosis is commonly seen in endemic countries. Cases of primary drug resistance are rare. There is a paucity of data related to primary drug resistance at extrapulmonary sites. Herein, a case of primary isoniazid mono-resistant extrapulmonary tuberculosis of the multiple right cervical lymph nodes is presented. This patient reported multiple swellings and discharging sinuses. A battery of investigations with an eye for finding drug resistance led to a definite diagnosis. He was initiated on an anti-tubercular regimen per the national guidelines. A detailed literature search revealed that no such case of primary isoniazid mono-resistant extrapulmonary tuberculosis presenting as cervical lymphadenitis has ever been reported.