What are the criteria to exclude Human Immunodeficiency Virus (HIV) infection in an infant born to an HIV-positive mother?

From the Guidelines

To exclude HIV infection in an infant born to an HIV-positive mother, the definitive exclusion requires two or more negative virologic tests, with at least one test performed at age ≥4 months, as recommended by the most recent guidelines 1. The testing protocol should include the following criteria:

• Two or more negative virologic tests, with at least one test performed at age ≥4 months
• Acceptable virologic tests include HIV DNA PCR and HIV RNA PCR, which directly detect the virus rather than antibodies
• The first test should be done within 48 hours of birth, the second at 1-2 months, and the third at 4-6 months of age
• Additionally, the infant should have no clinical symptoms suggestive of HIV infection
• Maternal antibodies can cross the placenta and persist in the infant for up to 18 months, making antibody tests unreliable before this age
• For complete exclusion, the infant should not be breastfed, as HIV can be transmitted through breast milk, and should have no other potential HIV exposures This testing protocol is crucial because early detection allows for prompt initiation of antiretroviral therapy, which significantly improves outcomes for HIV-infected infants, as supported by recent studies 1. Some key points to consider:
• The American Academy of Pediatrics recommends documented, routine HIV testing for all pregnant women in the United States after notifying the patient that testing will be performed, unless the patient declines HIV testing 1
• For women in labor with undocumented HIV-infection status during the current pregnancy, immediate maternal HIV testing with opt-out consent, using a rapid HIV antibody test, is recommended 1
• Positive HIV antibody screening test results should be confirmed with immunofluorescent antibody or Western blot assay 1
• For women with a positive rapid HIV antibody test result, antiretroviral prophylaxis should be administered promptly to the mother and newborn infant on the basis of the positive result of the rapid antibody test without waiting for results of confirmatory HIV testing 1

From the FDA Drug Label

2.3 Prevention of Maternal-Fetal HIV-1 Transmission 14.3 Prevention of Maternal-Fetal HIV-1 Transmission

To exclude HIV from an infant of an HIV mother, the criteria are not explicitly stated in the provided drug label. However, the label does mention the prevention of maternal-fetal HIV-1 transmission as an indication for the use of zidovudine.

• The label does not provide specific criteria to exclude HIV in infants.
• The diagnosis and exclusion of HIV in infants would typically involve clinical evaluation and laboratory tests, such as HIV DNA or RNA assays, which are not discussed in the label.
• The label only provides information on the use of zidovudine for the prevention of maternal-fetal HIV-1 transmission 2.

From the Research

Criteria to Exclude HIV from Infant of HIV Mother

To exclude HIV from an infant born to an HIV-positive mother, several criteria and strategies can be considered:

• Antiretroviral therapy for the mother during pregnancy, labor, and delivery, as well as for the infant after birth 3, 4, 5, 6
• Elective Cesarean section delivery to reduce the risk of mother-to-child transmission 3
• Avoidance of breastfeeding to prevent postnatal transmission 3, 4, 5
• Antiretroviral postexposure prophylaxis for the infant, with the type and duration depending on the mother's viral load and the infant's risk of transmission 4, 5, 6
• Monitoring of the infant's HIV status through regular testing 4

Antiretroviral Regimens

Different antiretroviral regimens have been studied for their efficacy in preventing mother-to-child transmission of HIV:

• Zidovudine monotherapy has been shown to reduce the risk of transmission by about two-thirds 3
• Combination regimens, such as zidovudine plus lamivudine, have been found to be more effective than zidovudine alone 3
• Nevirapine has been used as an alternative to zidovudine, with a two-dose oral regimen being as effective as a short-course zidovudine regimen 3
• Triple-combination antiretroviral therapy, including zidovudine, lamivudine, and nevirapine, has been found to be safe and effective for neonatal postexposure prophylaxis in high-risk HIV-exposed infants 6

Risk Factors for Vertical Transmission

Several risk factors have been identified for vertical transmission of HIV:

• Maternal seroconversion during pregnancy or breastfeeding 4
• High maternal plasma viral RNA load during pregnancy 4
• Advanced maternal HIV disease 4
• Lack of antiretroviral therapy during pregnancy, labor, and delivery 3, 4