A 40-year-old male presents with fever, weight loss, and enlarged, painless lymph nodes in his neck for the past month. He reports a history of close contact with a relative who had tuberculosis. What are the potential causes, and what are the next steps?
Given his symptoms and contact history, this patient could have lymph node tuberculosis (also known as scrofula or tuberculous lymphadenitis). Other differential diagnoses could include lymphoma, other infections such as mononucleosis or HIV, or metastatic cancer. The next step would be to perform a biopsy of one of the enlarged lymph nodes to confirm the diagnosis, which should include staining and culture for mycobacteria.