DISTRIBUTION OF BRAIN HIV LOAD IN AIDS

Approximately one quarter of patients with AIDS develop severe cogniti ve deficits called HIV-associated dementia complex (ADC), There is som e controversy regarding the importance of viral load in mediating neur ologic disease, With the advent of sensitive, quantitative and reprodu cible RNA assays for HIV load in plasma and CSF, we quantified viral l oad in brains from 10 autopsied HIV-infected subjects and 2 non-infect ed controls, The new quantitative HIV RNA assays showed general agreem ent with previously used semi-quantitative immunocytochemical assessme nts of HIV envelope protein, and were performed without professional s ubjective interpretation, All cases with very high revels of HIV in th e CSF, had high overall levels in the brain, suggesting that CSF viral loads exceeding 10(6) copies per mt may be a surrogate marker of high viral load in the brain, Levels of virus in the spleen showed no clea r association with those found in the brain, HIV RNA was not uniformly distributed throughout the brain, Selective regions, including basal ganglia and hippocampus, showed higher levels of virus than the cerebe llar cortex and mid-frontal cortical gray matter, Assessment of overal l brain viral load requires careful attention to regional quantitation .