Increasing intrathecal lymphocytosis and immunoglobulin G production in neurologically asymptomatic HIV-1 infection.

Cerebrospinal fluid from 34 human immunodeficiency virus (HIV-1) seropositive patients, only four of whom had HIV-related neurological symptoms, was examined by cytology, protein quantification, isoelectric focusing and specific serological tests. CSF lymphocytosis and evidence of intrathecal IgG production, found in 21 and 20 respectively of the 34 patients, correlated significantly with the duration of the infection. Increasing IgG index was found in two patients with repeated CSF examinations during greater than 7 years. Intrathecal HIV antibodies were detected on Western blot in 32/34 patients. HIV antigen test positive in 5/34 sera was negative in all 34 CSF samples. Intrathecal B cell activation seems to increase during the early HIV infection.