Kinetics of HIV-1 in cerebrospinal fluid and serum after zidovudine treatment.

Two patients with HIV-1 infection associated with neurological complications were repeatedly followed with cerebrospinal fluid (CSF) and serum analyses before, and 1 to 2.5 years after single zidovudine treatment. Retrospectively, HIV-RNA levels were analyzed with quantitative PCR assay. The number of HIV-RNA copies in CSF was decreased already 1 week after initiation of zidovudine, and continued to decrease during 5 months of follow up, while the serum levels increased during the same period. The difference between HIV levels in CSF and serum compartments following zidovudine treatment indicates that the CSF viral load does not merely reflect blood levels. Single zidovudine treatment did not reduce the viral load in CSF to non-detectable levels but had a better and more long-lasting anti-HIV effect in CSF than in peripheral blood.