Your diagnosis? A 12-year-old girl with latent tuberculosis presenting with nausea, vomiting and increasing frontal headache.

A 12-year-old girl with latent Mycobacterium tuberculosis infection and currently receiving prophylaxis with isoniazid presented with nausea, vomiting and increasing frontal headache. Toxicity to the anti-tuberculosis drug was suspected, but her symptoms persisted after isoniazid withdrawal. A computed tomography (CT) scan showed a brain mass to be present.