[Meningitis in subjects with human immunodeficiency virus infection]

Neurological complications are frequently observed in HIV-1 patients. Lumbar puncture (LP) and LSF analysis are two key diagnostic procedures.

To describe the etiology meningeal syndromes in a hospital series of HIV patients.

In this study, we present the different meningeal complications from 198 HIV-1 patients referred, for the last five years, to the HIV Center of the Hospital of University of Chile. The diagnosis of HIV-1 was done clinically plus a positive ELISA test, and confirmed by Western blot and/or PCR. In all cases with a possible neurological complication (52/198), a LP was performed. Cytochemical and microbiological studies, were done in each CSF sample. Serum CD4/CD8 lymphocytes number were determined by flow cytometry, and brain CT scan and/or MRI were obtained. From the 52 patients in whom a LP was done, 24 showed an abnormal CSF, compatible with the diagnosis of meningitis. The most frequent etiology (11/24) was infection by Cryptococcus neoformans, followed by Treponema pallidum (7/24). There were 3 cases of HIV-1 meningitis, and 3 other cases with lymphoma, varicella zoster and cytomegalovirus meningitis. The frequency of cryptococcal infection was similar to that reported in the literature, but two interesting observations were the high frequency of neurosyphilis and the absence of TBC meningitis. In our country, the VDRL/FTA-ABS serum tests are mandatory in HIV patients. If these tests were positive a LP was performed, and this could partially explain the high number of cases coinfected with neurosyphilis. There is an important prevalence of lung TBC in our country, and as a consequence there is a policy of immunization to all newborn. It is possible that the high prevalence of TBC "promotes" a more actively search for TBC infection, with an early diagnosis and treatment of pulmonary TBC, and so a more frequent prophylaxis therapy in HIV patients, without the development of TBC meningitis.