Pediatric HIV infection: neurologic and neuropsychologic findings.

Neurologic and neuropsychologic findings are early and important prognostic indicators of symptomatic HIV disease among infants and young children. The most common presentations include progressive encephalopathy, loss of motor milestones, and corticospinal tract abnormalities. It is hypothesized that, in some instances, the more severe neurologic manifestations of HIV noted in infancy may reflect the consequences of in utero HIV infection, or the increased vulnerability of infants to HIV infection during a time of rapid brain growth. Current research suggests that infants with basal ganglia calcification and those with plummeting or low CD4+ counts are at particular risk of severe central nervous disease progression. In contrast to infants and toddlers, older children and adolescents appear to demonstrate only subtle neurologic dysfunction until very late in their illness. Findings seen include attentional difficulties, fine motor tremors, visual sequencing problems, and depressive affect. One of the challenges for the 1990s will be rapidly to identify those infants who are at high risk of central nervous system disease progression, and to institute effective treatments that can halt the devastating effects of HIV on the developing brain. In addition to early identification of the high-risk infants, neuropsychologic, neuroimaging and laboratory measures need to be identified that will allow effective monitoring of responses to therapy.