HIVNET 024: Placental histology and mother to child transmission (MTCT) of HIV

Abstract

(MTCT) OF HIV ROBERT GOLDENBERG, VICTOR MUDENDA, TAHA TAHA, IRVING HOFFMAN, WAFAIE FAWZI, ELIZABETH BROWN, University of Alabama at Birmingham, Obstetrics/Gynecology, Birmingham, Alabama, University Teaching Hospital, Pathology, Lusaka, Zambia, Johns Hopkins University, Baltimore, Maryland, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, Harvard University, Boston, Massachusetts, Fred Hutchinson Cancer Research Center, Seattle, Washington OBJECTIVE: Studies performed prior to the use of antivirals have shown a relationship between histologic chorioamnionitis, (neutrophilic infiltrates in the chorioamnion) and MTCT of HIV. A recent publication describing nevirapine-treated women suggests MTCT of HIV is related to mononuclear, but not neutrophilic infiltration. STUDY DESIGN: During a trial of the use of antibiotics to reduce MTCT of HIV in 2098 HIV-infected nevirapine-treated women, we evaluated the relationship between neutrophilic and mononuclear infiltration of the decidual basalis, the chorioamnion and the umbilical cord, and MTCT of HIV. Marked infiltration was compared to none/slight. A single pathologist who had no clinical information at the time of the evaluation performed the histologic evaluation. Infant HIV infection was determined by PCR at birth and at 6 weeks. RESULTS: The rate of MTCT of HIV at birth was 7.3%, between birth and 4-6 weeks 7.5%, and total perinatal MTCT, 15.2%. (In the pre-nevirapine studies, the total MTCT rate was 25-30%.) Marked neutrophilic and mononuclear infiltration into the membranes (29% and 35%) and decidua (19% and 44%) were common in HIV-infected women. Neither marked neutrophilic nor mononuclear infiltration at any site was associated with infant HIV status at birth, with developing an HIV infection between birth and 6 weeks, or with infant HIV status at 6 weeks. For example, marked neutrophilic membrane infiltration vs none/slight was not associated with infant HIV status at birth (8.7 vs 7.3%, p=NS), the development of HIV between birth and 6 weeks (7.8 vs 6.7%, p=NS) or with HIV status at 6 weeks (15.3 vs 14.5%, p=NS). CONCLUSION: Despite previous reports of an association between chorioamnionitis and MTCT of HIV, this large study demonstrated no association between either neutrophilic or mononuclear inflammation at any site and MTCT of HIV. We hypothesize that the use of nevirapine in this, as opposed to many earlier studies, reduced the portion of MTCT of HIV associated with chorioamnionitis.