Perinatal AIDS: drugs of abuse and transplacental infection

Abstract

The number of children infected by the human immunodeficiency virus type-1 (HIV-1) who develop the acquired immunodeficiency syndrome (AIDS) continues to increase. While some children become infected after birth and others at the time of parturition, a significant percentage are infected during gestation and there is a positive correlation between maternal illicit intravenous drug use and fetal HIV-1 infection. Drugs can contribute in, at least, four ways to vertical transmission of HIV-1. These four ways are divisible into 2 main categories that are comprised of both direct and indirect mechanisms. For example, drugs of abuse can have a direct effect on the maternal-fetal interface. Cocaine is associated with vasculitis. If this occurs as a placentitis or chorioamnionitis, it can alter the permeability of these barriers to maternal blood and increase the number of potentially infected inflammatory cells in this tissue and as a result in the fetus. Another direct mechanism wherein drugs of abuse can increase the probability that a fetus will become infected is via an inflammatory reaction such as a vasculitis in the fetus rendering it more susceptible to viral infection. Drugs can also affect the course of HIV-1 infection via indirect mechanisms. An example of this may be by modulating the female immune system. This effect can exacerbate the woman's immunodeficiency and accelerate opportunistic infections. For example, cytomegalovirus infection resulting in placentitis might facilitate fetal HIV-1 infection. Lastly, a similar type of indirect mechanism can be postulated for the fetus wherein its developing immune system can be adversely effected.(ABSTRACT TRUNCATED AT 250 WORDS)