ABSTRACTINTRODUCTION: Antiretroviral therapy and prophylaxis during the antepartum, intrapartum and postpartum periods, cesarean delivery and avoidance of breast milk significantly reduce vertical transmission of HIV.OBJECTIVE:To evaluate the effectiveness prevention of mother-to-child transmission of HIV and determine the rate of vertical transmission in a public sexually transmitted infection and HIV referral center in Salvador, Bahia, in the period immediately prior to the initiation of universal antiretroviral therapy in pregnant women.METHODS:Cross-sectional study using data collected from medical records of children born to HIV infected mothers in Bahia from 2005 to 2008 who were referred to the Reference Center for Diagnosis and Research of Sexually Transmitted Diseases and HIV/AIDS for care.RESULTS:Of 232 HIV-exposed infants, 19 (8.2%) had confirmed HIV infection. One hundred eighty-eight (81%) mothers received antenatal care, 120 (52%) antepartum antiretroviral therapy or prophylaxis, and 168 (72%) intrapartum zidovudine. Two hundred twenty-three (96%) infants received zidovudine. In multivariable models, the combination of intrapartum and postpartum antiretroviral prophylaxis was associated with decreased adjusted odds of mother-to-child transmission.CONCLUSIONS:Low levels of antenatal screening and access to prevention of mother-to-child transmission were significant limitations in the cascade of prevention of mother-to-child transmission at our center in this period.

The null genotype for glutathione S-transferase (GST, EC 2.5.1.18) gene polymorphisms is considered a risk factor for leukemia in different populations. In this work we investigated the GSTT1 and GSTM1 polymorphisms using multiplex PCR in 53 patients with chronic myeloid leukemia (CML), 23 with acute promyelocytic leukemia (APL) and 304 apparently healthy controls. In this association study we found that the GSTT1null genotype was more frequent in our group of APL patients than in the control group [OR = 2.75 (95% CI = 1.10-6.88)], providing evidence that a deletion in the GSTT1 gene could be a risk factor for this type of leukemia.

Methylenetetrahydrofolate reductase (MTHFR: EC 1.5.1.20) polymorphisms are associated to acute lymphoid leukemia in different populations. We used the polymerase chain reaction and the restriction fragment length polymorphism method (PCR-RFLP) to investigate MTHFR C677T and A1298C polymorphism frequencies in 67 patients with chronic myeloid leukemia (CML), 27 with acute myeloid leukemia FAB subtype M3 (AML-M3) and 100 apparently healthy controls. The MTHFR mutant allele frequencies were as follows: CML = 17.2% for C677T, 21.6% for A1298C; AML-M3 = 22.2% for C677T, 24.1% for A1298C; and controls = 20.5% for C677T, 21% for A1298C. Taken together, our results provide evidence that MTHFR polymorphisms have no influence on the development of CML or AML-M3.