A 'brain tumor' in an intravenous drug abuser.

A male intravenous drug abuser who was infected with hepatitis B and C, presented with a slowly progressive hemiplegia. Contrast enhanced computerized tomography of the head showed a solitary ring-enhanced mass with surrounding edema. Clinically brain tumor was suspected but a brain biopsy confirmed cerebral toxoplasmosis. An HIV test was not considered until the result of brain biopsy. He also had lymphopenia and positive serum toxoplasma antibody. His subsequent HIV test was positive. He deteriorated after a brain biopsy. Empirical antitoxoplasma treatment is recommended in HIV-positive patients with ring-enhanced lesions with surrounding edema and with positive toxoplasma serology. Cerebral toxoplasmosis is still the commonest cerebral opportunistic infection in HIV-infected patients even though the incidence has declined with the use of antiretroviral therapy. It is often diagnosed in those patients as an initial presentation of HIV infection or in those who failed to attend for disease monitoring. Clinical features and differential diagnosis of cerebral toxoplasmosis in immunocompromised patients are discussed.