title: Early diagnosis of in utero and intrapartum HIV infection in infants prior to 6 weeks of age.
abstract: Early initiation of antiretroviral therapy reduces HIV-related infant mortality. The early peak of pediatric HIV-related deaths in South Africa occurs at 3 months of age, coinciding with the earliest age at which treatment is initiated following PCR testing at 6 weeks of age. Earlier diagnosis is necessary to reduce infant mortality. The performances of the Amplicor DNA PCR, COBAS AmpliPrep/COBAS TaqMan (CAP/CTM), and Aptima assays for detecting early HIV infection (acquired in utero and intrapartum) up to 6 weeks of age were compared. Dried blood spots (DBS) were collected at birth and at 2, 4, and 6 weeks from HIV-exposed infants enrolled in an observational cohort study in Johannesburg, South Africa. HIV status was determined at 6 weeks by DNA PCR on whole blood. Serial DBS samples from all HIV-infected infants and two HIV-uninfected, age-matched controls were tested with the 3 assays. Of 710 infants of known HIV status, 38 (5.4%) had in utero (n = 29) or intrapartum (n = 9) infections. By 14 weeks, when treatment should have been initiated, 13 (45%) in utero-infected and 2 (22%) intrapartum-infected infants had died or were lost to follow-up. The CAP/CTM and Aptima assays identified 76.3% of all infants with early HIV infections at birth and by 4 weeks were 96% sensitive. DNA PCR demonstrated lower sensitivities at birth and 4 weeks of 68.4% and 87.5%, respectively. All assays had the lowest sensitivity at 2 weeks of age. CAP/CTM was the only assay with 100% specificity at all ages. Testing at birth versus 6 weeks of age identifies a higher total number of HIV-infected infants, irrespective of the assay.
authors.affiliation: Paediatric HIV Diagnostic Syndicate, Wits Health Consortium, Johannesburg, South Africa.
authors.forename: Rivka R
authors.initials: RR
authors.lastname: Lilian
authors.forename: Emma
authors.initials: E
authors.lastname: Kalk
authors.forename: Kapila
authors.initials: K
authors.lastname: Bhowan
authors.forename: Leigh
authors.initials: L
authors.lastname: Berrie
authors.forename: Sergio
authors.initials: S
authors.lastname: Carmona
authors.forename: Karl
authors.initials: K
authors.lastname: Technau
authors.forename: Gayle G
authors.initials: GG
authors.lastname: Sherman
mesh_terms: D000328:Adult; D001769:Blood / Q000821:virology; D015331:Cohort Studies; D042241:Early Diagnosis; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis*; D006678:HIV / Q000302:isolation & purification; D015658:HIV Infections / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013019:South Africa; D014773:Virology / Q000379:methods*; D055815:Young Adult