An avoidable transmission of HIV from mother to child.

690 CMAJ, April 5, 2011, 183(6) © 2011 Canadian Medical Association or its licensors A29-year-old married woman, an immigrant from sub-Saharan Africa, presented to the Southern Alberta HIV Clinic at week 26 of pregnancy after receiving a positive test result from prenatal HIV screening. She had a university-level education, was fluent in English and agreed to start highly active antiretroviral therapy (HAART). At 28 weeks’ gestation, the patient began taking zidovudine (300 mg twice daily), lamivudine (150 mg twice daily) and nelfinavir (1.25 g twice daily) both for her health and to reduce the risk of perinatal HIV transmission. During her pregnancy, the patient repeatedly reported consistent adherence to the HAART without adverse events. Her HIV viral loads measured with the NucliSens HIV-1 QT assay (bioMérieux, USA) and CD4 counts are shown in Table 1. Although the CD4 count remained at about 0.20 × 10/L, the viral load remained undetectable. While a patient at the HIV clinic, the woman had seven visits with her HIV specialist (who was also her child’s pediatrician) and had numerous pharmacy, dietary and nursing consultations. The patient also regularly attended a separate high-risk pregnancy clinic for extra counselling before delivery. During labour and delivery, the patient de clined a cesarean section. She was given intravenous zidovudine at a loading dose of 2 mg per kilogram of pregnancy weight infused over one hour, with hourly infusions of 1 mg/kg until the umbilical cord was clamped. Post partum, the baby was given zidovudine (2 mg/kg orally every six hours) for six weeks. The mother was strongly advised against breastfeeding to avoid the risk of HIV transmission to her child and was offered free formula to support this approach. Post partum, the mother received weekly home visits by a nurse from the high-risk pregnancy clinic for more counselling and medication adjustments for her infant. She reported mild depression but declined interventions. Slightly erratic attendance at the HIV clinic was attributed to family and child care issues. She reported ongoing adherence to the HAART and feeding with formula only. At birth and at three and eight months of age, the child was found to be HIV-negative using polymerase chain reaction testing. At 12 months of age, the test results were indeterminate. Testing at 13 months showed that the baby had the same pansensitive HIV-1, group M, subtype G virus that the mother had.