My cousin has just been diagnosed with HIV. He has had a CT scan that showed an abnormality. But because he has no insurance we have been trying to get a diagnosis without a biopsy. What are other ways to tell if it is a brain tumor or toxoplasmosis? He is currently being treated for toxoplasmosis.

Although the best way to get an accurate diagnosis is do to a biopsy, health care professionals will often treat for two weeks with medications which target the toxoplasmosis, an opportunistic infection seen in HIV-infected individuals. Things which would make toxoplasmosis more likely would be if your cousin were to have a positive toxoplasmosis test in his blood and if he were not be taking Bactrim, a commonly used antibiotic in HIV patients. Things which would make lymphoma more likely would be if his toxoplasmosis test were to be negative and if he were to be taking Bactrim. Patients who take Bactrim as part as prophylactic medication to prevent Pneumocystis carinii pneumonia (PCP pneumonia, another opportunistic infection) get some prevention from toxoplasmosis since Bactrim is active in both of these conditions (PCP pneumonia and toxoplasmosis). The bottom line is that if your cousin's situation doesn't improve rapidly, he will probably need a biopsy to get an accurate diagnosis. The good news is that once his condition is diagnosed, treatment is pretty good for these conditions.