[Brain biopsies in HIV-infected patients].

Stereotactic brain biopsies of 25 HIV-seropositive patients (age range between 20 and 56 years, 23 males, 2 females) were retrospectively studied. Biopsy material was examined cytologically, histologically, immunohistochemically and electron microscopically. A definitive diagnosis could be established in 23 cases (92%). Diagnosis included non-Hodgkin's lymphoma (10 cases), toxoplasmosis (10 cases), progressive multifocal leukoencephalopathy (PML) (2 cases) and combined toxoplasmosis and lymphoma (1 case). Two biopsies were non-diagnostic. All lymphomas were B-cell lymphomas of high malignancy including one K1-lymphoma. In six cases, in which autopsy was performed, biopsy diagnosis could be confirmed. In one patient suffering from toxoplasmosis, autopsy demonstrated an additional cytomegalovirus infection. Conventional histology was not sufficiently decisive for toxoplasmosis, for some lymphomas and for PML. Stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions.