Lamivudine-zidovudine combination for prevention of maternal-infant transmission of HIV-1

Transplacental haemorrhage may explain the intrapartum transmission of HIV. A pilot study uses flow cytometry to quantify maternal red blood cells in infants born vaginally or by caesarean section

Intrapartum transmission is epidemiologically important for some viruses such as HIV and hepatitis B virus, but its precise mechanism is unknown. We hypothesised that the ability of elective caesarean section to prevent HIV may be due to prevention of transplacental microtransfusions of blood during labour. Their frequency is not known so we performed a pilot study which showed evidence of transplacental transfusion from mother to fetus in one of ten mother-infant pairs delivering vaginally and none of ten delivering by elective caesarean section. We conclude that transplacental transfusion occurs and is one possible mechanism for the intrapartum transmission of viruses from mother to baby.

Evaluation and management of the infant exposed to HIV-1 in the United States

The pediatrician plays a key role in the prevention of mother-to-child transmission of HIV-1 infection. For infants born to women with HIV-1 infection identified during pregnancy, the pediatrician ensures that antiretroviral prophylaxis is provided to the infant to decrease the risk of acquiring HIV-1 infection and promotes avoidance of postnatal HIV-1 transmission by advising HIV-1-infected women not to breastfeed. The pediatrician should perform HIV-1 antibody testing for infants born to women whose HIV-1 infection status was not determined during pregnancy or labor. For HIV-1-exposed infants, the pediatrician monitors the infant for early determination of HIV-1 infection status and for possible short- and long-term toxicity from antiretroviral exposures. Provision of chemoprophylaxis for Pneumocystis jiroveci pneumonia and support of families living with HIV-1 by providing counseling to parents or caregivers are also important components of care.

Pharmacologic and nonpharmacologic options for the management of HIV infection during pregnancy

Over the past decade, significant advances have been made in the treatment of HIV-1 infection using both pharmacologic and nonpharmacologic strategies to prevent mother-to-child transmission (MTCT). Optimal prevention of the MTCT of HIV requires antiretroviral drugs (ARV) during pregnancy, during labor, and to the infant. ARVs reduce viral replication, lowering maternal plasma viral load and thus the likelihood of MTCT. Postexposure prophylaxis of ARV agents in newborns protect against infection following potential exposure to maternal HIV during birth. In general, the choice of an ARV for treatment of HIV-infected women during pregnancy is complicated by the need to consider the effectiveness of the therapy for the maternal disease as well as the teratogenic or teratotoxic potential of these drugs. Clinicians managing HIV in pregnancy need to discuss the potential risks and benefits of available therapy options so that mothers can make informed decisions in choosing the best treatment regimen for themselves and for their children.

Cost-effectiveness estimates for antenatal HIV testing in the Netherlands

This paper provides an estimation of the lifetime health-care cost of HIV-infected children and an update of the cost-effectiveness of universal HIV-screening of pregnant women in Amsterdam (The Netherlands). During 2003-2005, we collected data concerning the prevalence of newly diagnosed HIV-infected pregnant women in Amsterdam. Also, data on resource utilization and HAART regimen for HIV-infected children was gathered from a national registry. Using Kaplan-Meier survival analysis, we estimated the life-expectancy of a vertically HIV-infected child at 19 years, with the corresponding lifetime health-care costs of 179,974 Euros. HIV-screening of pregnant women could prevent 2.4 HIV transmissions annually in Amsterdam, based on an estimated prevalence of nine yet undiagnosed HIV-positive pregnant women per 10,000 pregnancies. We show that universal HIV screening during pregnancy generates significant net cost savings and health benefits in most situations. Universal antenatal HIV screening is justified in Amsterdam from a health-economic point of view.

Fetal allostimulation of maternal cells: a potential mechanism for perinatal HIV transmission following obstetrical hemorrhage

Our aim was to elucidate the mechanism by which HIV transmission is increased following obstetrical hemorrhage. We investigated whether fetal allostimulation of maternal cells, which could occur following fetal-to-maternal hemorrhage, increases proliferation, HIV replication, and cellular activation. Peripheral blood mononuclear cells (PBMCs) were collected from HIV-infected mothers and their infants to assess maternal-fetal allostimulation. Responses were compared to allostimulation with unrelated donors. Maternal and fetal cells were cocultured to assess allogeneic stimulation. Cell proliferation was measured by [(3)H]thymidine incorporation and cell activation was assessed via fluorochrome-labeled antibody staining and flow cytometric analysis. Virus production from HIV-infected maternal cells was quantitated by p24 enzyme-linked immunosorbent assay or by branched chain DNA assay. Allostimulation with fetal cells led to maternal cell proliferation. In women with unsuppressed viral loads, virus release was also enhanced following allostimulation of maternal cells with fetal cells. Fetal cells are capable of allogeneically stimulating maternal cells, with responses comparable to those seen following allostimulation with unrelated donors. Allostimulation of maternal cells by fetal cells results in statistically significant increases in proliferation and enhanced HIV replication, suggesting a possible physiological mechanism for mother-to-child transmission of HIV in women with obstetrical hemorrhage.

Antiretroviral drugs for preventing mother-to-child transmission of HIV in sub-Saharan Africa: balancing efficacy and infant toxicity

OBJECTIVE

Antiretroviral drugs can prevent mother-to-child transmission of HIV infection, but in-utero antiretroviral exposure may be associated with neurologic symptoms due to mitochondrial toxicity. We sought to identify the currently recommended regimen to prevent mother-to-child transmission that optimally balances risks of pediatric HIV infection and neurologic mitochondrial toxicity.

DESIGN

Published MTCT and mitochondrial toxicity data were used in a decision analytic model of MTCT among women in sub-Saharan Africa.

METHODS

We investigated the HIV and mitochondrial toxicity risks associated with no antiretroviral prophylaxis and five recommended regimens ranging from single-dose nevirapine to three-drug antiretroviral therapy (ART). Sensitivity analyses varied all parameters, including infant feeding strategy and the disability of mitochondrial toxicity relative to HIV.

RESULTS

Provision of no antiretroviral drugs is the least effective and least toxic strategy, with 18-month HIV risk of 30.4% and mitochondrial toxicity risk of 0.2% (breastfed infants). With increasing drug number and duration, HIV risk decreases markedly (to 4.9% with three-drug ART), but mitochondrial toxicity risk also increases (to 2.2%, also with three-drug ART). Despite increased toxicity, three-drug ART minimizes total adverse pediatric outcomes (HIV plus mitochondrial toxicity), unless the highest published risks are true for both HIV and mitochondrial toxicity, or the disability from mitochondrial toxicity exceeds 6.4 times that of HIV infection.

CONCLUSION

The risk of pediatric mitochondrial toxicity from effective regimens to prevent mother-to-child transmission is at least an order of magnitude lower than the risk of HIV infection associated with less-effective regimens. Concern regarding mitochondrial toxicity should not currently limit the use of three-drug ART to prevent mother-to-child transmission where it is available.

HIV testing and prophylaxis to prevent mother-to-child transmission in the United States

Universal HIV testing of pregnant women in the United States is the key to prevention of mother-to-child transmission of HIV. Repeat testing in the third trimester and rapid HIV testing at labor and delivery are additional strategies to further reduce the rate of perinatal HIV transmission. Prevention of mother-to-child transmission of HIV is most effective when antiretroviral drugs are received by the mother during her pregnancy and continued through delivery and then administered to the infant after birth. Antiretroviral drugs are effective in reducing the risk of mother-to-child transmission of HIV even when prophylaxis is started for the infant soon after birth. New rapid testing methods allow identification of HIV-infected women or HIV-exposed infants in 20 to 60 minutes. 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 ("opt-out" consent or "right of refusal"). 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. Positive HIV antibody screening test results should be confirmed with immunofluorescent antibody or Western blot assay. 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. If the confirmatory test result is negative, then prophylaxis should be discontinued. For a newborn infant whose mother's HIV serostatus is unknown, the health care professional should perform rapid HIV antibody testing on the mother or on the newborn infant, with results reported to the health care professional no later than 12 hours after the infant's birth. If the rapid HIV antibody test result is positive, antiretroviral prophylaxis should be instituted as soon as possible after birth but certainly by 12 hours after delivery, pending completion of confirmatory HIV testing. The mother should be counseled not to breastfeed the infant. Assistance with immediate initiation of hand and pump expression to stimulate milk production should be offered to the mother, given the possibility that the confirmatory test result may be negative. If the confirmatory test result is negative, then prophylaxis should be stopped and breastfeeding may be initiated. If the confirmatory test result is positive, infants should receive antiretroviral prophylaxis for 6 weeks after birth, and the mother should not breastfeed the infant.

Current and future antiretroviral treatment options in paediatric HIV infection

Because of a lack of prevention policies or problems in implementing prevention of mother-to-child transmission (P-MTCT), most of the 1500 daily new HIV infections in children aged<15 years are caused by MTCT. Fifteen percent of all HIV-infected individuals are children, but the vast majority lack access to highly active antiretroviral therapy (HAART), which can drastically reduce morbidity and mortality. There are 22 antiretroviral drugs currently approved by the US FDA for use in the treatment of HIV-infected adults and adolescents, but only 12 of these drugs are approved for use in children. Antiretroviral drugs belong to four major classes: nucleoside and nucleotide analogue reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors and fusion inhibitors. According to international guidelines developed by organizations including WHO, the Paediatric European Network for Treatment of AIDS (PENTA) and the US National Institutes of Health (US-NIH), the treatment of choice for HIV-infected children and adults is a combination of two NRTIs (backbone treatment) plus a third potent agent from a different class, either an NNRTI or a ritonavir-boosted protease inhibitor. There are specific challenges in treating HIV-infected children, including uncertainty about the best time to start treatment, the need for more paediatric formulations, the lack of pharmacokinetic studies for new drugs, and incomplete dosing guidelines. Furthermore, the most appropriate regimen for an individual child depends on a variety of factors, including the age of the child; the availability of appropriate drug formulations; the potency, complexity and toxicity of the drug regimen; the home situation; the child and caregiver's ability to adhere to the regimen; and the child's antiretroviral treatment history. In addition, antiretroviral drugs are not licensed for all age groups and the drugs are often not affordable. This review describes NNRTI and protease inhibitors as key components of first- and second-line antiretroviral therapy (ART), focusing on the rationale for choosing an NNRTI- versus protease inhibitor-based regimen based on the results of available phase II and III studies. Some of the new agents available for children as second-line and salvage therapy both on- and off-label are also discussed. The drug regimens described in this review are relevant to clinicians in developed and developing countries. The availability of new, potent compounds with different resistance and toxicity profiles may represent an alternative option to interclass switching and could redefine ART strategy, including the option of first-line NRTI-sparing regimens.

Biomedical interventions to prevent HIV infection: evidence, challenges, and way forward

Intensive research efforts for more than two decades have not yet resulted in an HIV vaccine of even moderate effectiveness. However, some progress has been made with other biomedical interventions, albeit on the basis of inconsistent levels of evidence. The male condom, if used correctly and consistently, has been proven in observational studies to be very effective in blocking HIV transmission during sexual intercourse; and, in three randomised trials, male circumcision was protective against HIV acquisition among men. Treatment of sexually transmitted infections, a public health intervention in its own right, has had mixed results, depending in part on the epidemic context in which the approach was assessed. Finally, oral and topical antiretroviral compounds are being assessed for their role in reduction of HIV transmission during sexual intercourse. Research on biomedical interventions poses formidable challenges. Difficulties with product adherence and the possibility of sexual disinhibition are important concerns. Biomedical interventions will need to be part of an integrative package that includes biomedical, behavioural, and structural interventions. Assessment of such multicomponent approaches with moderate effects is difficult. Issues to be considered include the nature of control groups and the effect of adherence on the true effectiveness of the intervention.

Prevention of mother-to-child HIV transmission: similar access for sub-Sahara African immigrants and for French women?

OBJECTIVE

: To investigate whether mother-to-child transmission (MTCT) management and rate differed between African immigrants and French-born women delivering in France.

METHODS

: MTCT strategies were studied among human immunodeficiency virus type 1-infected women delivering between 1984 and 2007 in the multicenter French Perinatal Cohort, according to geographical origin.

RESULTS

: Among 9245 pregnancies (in 7090 women), the proportion of African mothers increased from 12% in 1984-1986 to 64% in 2003-2004. African women had later access to care than French women, even in recent years (1997-2004). They more often discovered their HIV infection during pregnancy (40.6 vs. 11.5%, P < 0.001), started prenatal care in the third trimester (14.1 vs. 9.8%, P < 0.001) and started antiretroviral therapy after 32 weeks gestation (7.6 vs. 4.1%, P < 0.001). The association with late treatment initiation disappeared when adjusted for late HIV diagnosis and prenatal care (adjusted odds ratio 1.0, 95% confidence interval 0.7-1.4). African and French women did not differ in terms of access to highly active antiretroviral therapy, nor for substandard management such as vaginal delivery with uncontrolled viral load, lack of intrapartum and postpartum treatment or breastfeeding. The MTCT rate was higher for African than for French women receiving antiretroviral therapy (1.8 vs. 0.8%, P = 0.02), but the difference was no longer significant after adjustment for main transmission risk factors (adjusted odds ratio = 1.7, 95% confidence interval 0.8-3.7, P = 0.17). MTCT did not differ among 2110 term deliveries with maternal viral load less than 400 copies/ml, (0.8 vs. 0.6%, P = 0.5).

CONCLUSION

: African immigrants more often had late HIV screening in pregnancy than French-born women, but had similar access to MTCT prevention, once the infection was diagnosed.

Trypanosoma cruzi (Chagas' disease agent) reduces HIV-1 replication in human placenta

Background

Several factors determine the risk of HIV mother-to-child transmission (MTCT), such as coinfections in placentas from HIV-1 positive mothers with other pathogens. Chagas' disease is one of the most endemic zoonoses in Latin America, caused by the protozoan Trypanosoma cruzi. The purpose of the study was to determine whether T. cruzi modifies HIV infection of the placenta at the tissue or cellular level.

Results

Simple and double infections were carried out on a placental histoculture system (chorionic villi isolated from term placentas from HIV and Chagas negative mothers) and on the choriocarcinoma BeWo cell line. Trypomastigotes of T. cruzi (VD lethal strain), either purified from mouse blood or from Vero cell cultures, 24 h-supernatants of blood and cellular trypomastigotes, and the VSV-G pseudotyped HIV-1 reporter virus were used for the coinfections. Viral transduction was evaluated by quantification of luciferase activity. Coinfection with whole trypomastigotes, either from mouse blood or from cell cultures, decreased viral pseudotype luciferase activity in placental histocultures. Similar results were obtained from BeWo cells. Supernatants of stimulated histocultures were used for the simultaneous determination of 29 cytokines and chemokines with the Luminex technology. In histocultures infected with trypomastigotes, as well as in coinfected tissues, IL-6, IL-8, IP-10 and MCP-1 production was significantly lower than in controls or HIV-1 transducted tissue. A similar decrease was observed in histocultures treated with 24 h-supernatants of blood trypomastigotes, but not in coinfected tissues.

Conclusion

Our results demonstrated that the presence of an intracellular pathogen, such as T. cruzi, is able to impair HIV-1 transduction in an in vitro system of human placental histoculture. Direct effects of the parasite on cellular structures as well as on cellular/viral proteins essential for HIV-1 replication might influence viral transduction in this model. Nonetheless, additional mechanisms including modulation of cytokines/chemokines at placental level could not be excluded in the inhibition observed. Further experiments need to be conducted in order to elucidate the mechanism(s) involved in this phenomenon. Therefore, coinfection with T. cruzi may have a deleterious effect on HIV-1 transduction and thus could play an important role in viral outcome at the placental level.

The Status of HIV-1 Resistance to Antiretroviral drugs in Sub-Saharan Africa

Access to highly active antiretroviral therapy (HAART) for persons infected with HIV in sub-Saharan Africa has greatly improved over the past few years. However, data on long-term clinical outcomes of Africans receiving HAART, patterns of HIV resistance to antiretroviral drugs and implications of HIV type-1 (HIV-1) subtype diversity in Africa for resistance, are limited. In resource-limited settings, concerns have been raised that deficiencies in health systems could create the conditions for accelerated development of resistance. Coordinated surveillance systems are being established to assess the emergence of resistance and the factors associated with resistance development, and to create the possibility for adjusting treatment guidelines as necessary. The purpose of this report is to review the literature on HIV-1 resistance to antiretroviral drugs in sub-Saharan Africa, in relation to the drug regimens used in Africa, HIV-1 subtype diversity and overall prevalence of resistance. The report focuses on resistance associated with treatment, prevention of mother-to-child transmission and transmitted resistance. It also outlines priorities for public health action and research.

Antiretroviral resistance among HIV type 1-infected women first exposed to antiretrovirals during pregnancy: plasma versus PBMCs

Resistance-associated mutations (RAMs) in plasma samples from HIV-1-infected women who received antiretroviral (ARV) prophylaxis during pregnancy was assessed and correlated with the detection of RAMs in peripheral blood mononuclear cells (PMBCs). The study population was composed of HIV-1-infected women enrolled in a prospective cohort study in Latin America and the Caribbean (NISDI Perinatal Study) as of March 1, 2005, who were diagnosed with HIV-1 infection during the current pregnancy, who received ARVs during pregnancy for prevention of mother-to-child transmission of HIV-1, and who were followed through at least the 6-12 week postpartum visit. Plasma samples collected at enrollment during pregnancy and at 6-12 weeks postpartum were assayed for RAMs. Plasma results were compared to previously described PBMC results from the same study population. Of 819 enrolled subjects, 197 met the eligibility criteria. Nucleic acid amplification was accomplished in 123 plasma samples at enrollment or 6-12 weeks postpartum, and RAMs were detected in 22 (17.9%; 95%CI: 11.7-25.9%). Previous analyses had demonstrated detection of RAMs in PBMCs in 19 (16.1%). There was high concordance between RAMs detected in plasma and PBMC samples, with only eight discordant pairs. The prevalence of RAMs among these pregnant, HIV-1-infected women is high (15%). Rates of detection of RAMs in plasma and PBMC samples were similar.

Pregnancy outcomes in women with HIV type-1 receiving a lopinavir/ritonavir-containing regimen

Background

The pregnancy-related adverse effects of antiretroviral therapy (ART) have yielded discordant results, which could be explained in part by the heterogeneity of ART protocols. The objective of our study was to explore whether lopinavir/ritonavir (LPV/r) exposure during pregnancy is associated with adverse outcomes.

Methods

Data on 100 consecutive HIV type-1 (HIV-1)-infected women receiving LPV/r during pregnancy and who delivered after 15 weeks gestational age (GA) between January 2003 and June 2007 in a single centre were analysed. For each HIV-1-infected woman, two uninfected women matched by age, parity and geographical origin were selected among patients delivering during the same period. Preterm delivery (PTD), vasculoplacental complications, gestational glucose intolerance and post-partum complication rates were compared between cases and controls. Factors associated with PTD and post-partum complications were assessed in HIV-1-infected women by a logistic regression model.

Results

Rates of vasculoplacental complication and gestational glucose intolerance were not higher among HIV-1-infected women than in controls. PTD was higher in HIV-1-infected women (21%) than in controls (10%; P<0.01). In HIV-1-infected women, PTD was associated with HIV-1 RNA level ≥50 copies/ml at delivery (adjusted odds ratio 6.15, 95% confidence interval 1.83–20.63; P=0.003). No association was found between occurrence of PTD and LPV/r exposure before 14 weeks GA.

Conclusions

In this population of HIV-1-infected pregnant women receiving LPV/r, the risk of PTD was higher than in HIV-1-uninfected controls. As PTD risk was not associated with early exposure to LPV/r, these data support current guidelines to initiate ART earlier in pregnancy.

[Second pregnancies in HIV-1-infected women. A prospective monocentric study]

OBJECTIVES

To evaluate the influence of successive pregnancies on the materno-foetal prognosis in a population of HIV-infected women. Clinical, biological data and treatment strategies were compared during iterative pregnancies.

PATIENTS AND METHODS

We conducted a monocentric prospective study between August 1995 and January 2007 in a French university hospital (Nice).

RESULTS

Twenty-six HIV-infected women had two consecutive pregnancies during our study. We noticed an increase in CD4 cell count between the two pregnancies. Viral load variations were non significant. The maternal's prophylaxis changed. Percentage of HAART increased from 26 to 54%. Modes of delivery, HIV or treatments side-effects remained the same between the successive pregnancies.

DISCUSSION AND CONCLUSION

Successive pregnancies do not seem to influence the materno-foetal prognosis related to HIV infection.

Sorologia anti-HIV e aconselhamento pré-teste em gestantes na região noroeste do Paraná, Brasil

OBJETIVOS: analisar a cobertura do aconselhamento e do teste anti-HIV, e identificar fatores associados à sua realização no pré-natal. MÉTODOS: estudo transversal, com mulheres de cinco municípios do Noroeste do Paraná, Brasil, com partos entre janeiro e março de 2003, identificadas a partir dos sistemas de informação. Os dados foram obtidos em entrevistas domiciliares. Considerou-se teste realizado quando havia registro do resultado do exame para HIV no cartão de gestante ou no laboratório de referência. As análises estatísticas foram feitas utilizando o teste do χ2 e exato de Fisher (α=0,05). RESULTADOS: das 435 mulheres entrevistadas, todas foram acompanhadas no pré-natal, com cobertura do teste anti-HIV de 89,6% - [IC95%: 86,8-92,4]. Não foram evidenciadas associações significativas entre a realização do teste e as variáveis sócio-demográficas, de vulnerabilidade e da assistência pré-natal. Embora a maioria tenha sido testada, apenas 13,6% relataram ter recebido aconselhamento pré-teste. CONCLUSÕES: a cobertura do teste anti-HIV durante a gestação foi satisfatória. A não-associação entre a realização do teste e as variáveis estudadas sugere que a sua solicitação se dá indistintamente, conforme recomendação do Ministério da Saúde. Porém, a baixa freqüência do aconselhamento e o atraso no recebimento do resultado dos exames são indicativos de problemas na atenção pré-natal.

18-month effectiveness of short-course antiretroviral regimens combined with alternatives to breastfeeding to prevent HIV mother-to-child transmission

Objective

We assessed the 18-month effectiveness of short-course (sc) antiretroviral peripartum regimens combined with alternatives to prolonged breastfeeding to prevent mother-to-child transmission (MTCT) of HIV-1 in Abidjan, Côte d'Ivoire.

Methodology

HIV-1 infected pregnant women received from ≥32–36 weeks of gestation scZidovudine (ZDV)+/−Lamivudine (3TC)+single-dose Nevirapine (sdNVP) at delivery within the ANRS 1201/1202 DITRAME-Plus cohort (2001–2003). Neonates received a sdNVP+7-day ZDV prophylaxis. Two infant-feeding interventions were systematically offered free of charge: formula-feeding or exclusive shortened breastfeeding with early cessation from four months. The reference group was the ANRS 049a DITRAME cohort (1994–2000) exposed to scZDV from 36 weeks, then to prolonged breastfeeding. Pediatric HIV infection was defined by a positive plasma HIV-1 RNA at any age, or if aged ≥18 months, a positive HIV-1 serology. Turnbull estimates of cumulative transmission risks (CTR) and effectiveness (HIV-free survival) were compared by exposure group using a Cox model.

Findings

Among 926 live-born children enrolled, 107 (11.6%) were HIV-infected at 18 months. CTRs were 22.3% (95% confidence interval[CI]:16–30%) in the 238 ZDV long-term breastfed reference group, 15.9% (CI:10–27%) in the 169 ZDV+sdNVP shortened breastfed group; 9.4% (CI:6–14%) in the 195 ZDV+sdNVP formula-fed group; 6.8% (CI:4–11%) in the 198 ZDV+3TC+sdNVP shortened breastfed group, and 5.6% (CI:2–10%) in the 126 ZDV+3TC+sdNVP formula-fed group. Each combination had a significantly higher effectiveness than the ZDV long-term breastfed group except for ZDV+sdNVP shortened breastfed children, ranging from 51% (CI:20–70%) for ZDV+sdNVP formula fed children to 63% (CI:40–80%) for ZDV+3TC+NVPsd shortened breastfed children, after adjustment for maternal eligibility for antiretroviral therapy (ART), home delivery and low birth-weight. Substantial MTCT risk reductions are reachable in Africa, even in short-term breastfed children. The two sc antiretroviral combinations associated to any of the two infant feeding interventions, formula-feeding and shortened breastfeeding, reduce significantly MTCT with long-term benefit until age 18 months and without increasing mortality.

Maternal 12-month response to antiretroviral therapy following prevention of mother-to-child transmission of HIV type 1, Ivory Coast, 2003-2006

OBJECTIVE

Our aim was to study the response to antiretroviral treatment among women exposed to single-dose nevirapine (NVP) and/or short-course zidovudine (ZDV; with or without lamivudine [3TC]) for the prevention of mother-to-child transmission of human immunodeficiency virus (HIV) infection.

METHODS

All HIV type 1-infected women who initiated antiretroviral treatment with stavudine or ZDV, 3TC, and NVP or efavirenz were eligible for the MTCT-Plus program in Abidjan, Ivory Coast. Exposed women had received either single-dose NVP alone or short-course ZDV (with or without 3TC) plus single-dose NVP during previous pregnancy. Genotypic resistance testing was performed at week 4 after delivery. Virologic failure was defined as a plasma HIV RNA level >500 copies/mL 12 months after initiation of antiretroviral treatment.

RESULTS

Among 247 women who received antiretroviral treatment, 109 (44%) were unexposed; 81 had received short-course ZDV with 3TC, as well as single-dose NVP; 5 had received short-course ZDV plus 3TC; 50 had received short-course ZDV plus single-dose NVP; and 2 had received single-dose NVP alone. No ZDV mutation was detected in the 115 women whose specimens were available for genotypic testing; 11 (15.1%) of 73 women with 3TC exposure who were tested after delivery had 3TC resistance mutations. Three (4.3%) of 69 women exposed to short-course ZDV and 3TC plus single-dose NVP and 16 (38.1%) of 42 women exposed to short-course ZDV plus single-dose NVP had NVP resistance mutations. Antiretroviral treatment was initiated a median of 21 months after the intervention to prevent mother-to-child HIV transmission (median CD4(+) T lymphocyte count, 188 cells/mm(3)). Month 12 virologic failure was identified in 42 (19.2%) of 219 women for whom data were available, and multivariate analysis revealed that it was associated with poor adherence to treatment (adjusted odds ratio [aOR], 12.7; 95% confidence interval [CI], 3.0-53.9), postpartum 3TC resistance mutations (aOR, 6.9; 95% CI, 1.1-42.9), and a baseline CD4(+) T lymphocyte count <200 cells/mm(3) (aOR, 0.3; 95% CI, 0.2-0.8). NVP resistance was not associated with virological failure (aOR, 1.8; 95% CI, 0.5-6.5).

CONCLUSIONS

Our study found that poor adherence and 3TC resistance acquired after the intervention to prevent mother-to-child transmission of HIV infection were associated with virologic failure in women who initiated antiretroviral treatment.

Mother-to-child HIV transmission despite antiretroviral therapy in the ANRS French Perinatal Cohort

OBJECTIVE

To identify factors associated with mother-to-child HIV-1 transmission (MTCT) from mothers receiving antenatal antiretroviral therapy.

DESIGN

The French Perinatal Cohort (EPF), a multicenter prospective cohort of HIV-infected pregnant women and their children.

METHODS

Univariate analysis and logistic regression, with child HIV status as dependent variable, were conducted among 5271 mothers who received antiretroviral therapy during pregnancy, delivered between 1997 and 2004 and did not breastfeed.

RESULTS

The MTCT rate was 1.3% [67/5271; 95% confidence interval (CI), 1.0-1.6]. It was as low as 0.4% (5/1338; 95% CI, 0.1-0.9) in term births with maternal HIV-1 RNA level at delivery below 50 copies/ml. MTCT increased with viral load, short duration of antiretroviral therapy, female gender and severe premature delivery: 6.6% before 33 weeks versus 1.2% at 37 weeks or more (P < 0.001). The type of antiretroviral therapy was not associated with transmission. Intrapartum therapy was associated with four-fold lower MTCT (P = 0.04) in case of virological failure (> 10 000 copies/ml). Elective cesarean section tended to be inversely associated with MTCT in the overall population, but not in mothers who delivered at term with viral load < 400 copies/ml [odds ratio (OR), 0.83; 95% CI, 0.29-2.39; P = 0.37]. Among them, only duration of antenatal therapy was associated with transmission (OR by week, 0.94; 95% CI, 0.90-0.99; P = 0.03).

CONCLUSIONS

Low maternal plasma viral load is the key factor for preventing MTCT. Benefits in terms of MTCT reduction may be expected from early antiretroviral prophylaxis. The potential toxicity of prolonged antiretroviral use in pregnancy should be evaluated.

Infant feeding and HIV in Sub-Saharan Africa: what lies beneath the dilemma?

The debate over how to best guide HIV-infected mothers in resource-poor settings on infant feeding is more than two decades old. Globally, breastfeeding is responsible for approximately 300,000 HIV infections per year, while at the same time, UNICEF estimates that not breastfeeding (formula feeding with contaminated water) is responsible for 1.5 million child deaths per year. The largest burden of these infections and deaths occur in Sub-Saharan Africa. Using this region as an example of the burden faced more generally in other resource-poor settings, we contrast the evolution of the clinical standard of care for infant feeding with HIV-infected mothers in high-income countries to the current international clinical guidelines for HIV-infected mothers and infant feeding in resource-poor settings. While the international guidelines of exclusive breastfeeding for a 6-month period seem to offer the least-worst strategy for reducing mother-to-child transmission of HIV during infancy while conferring some immunity through breastfeeding post-6 months, we argue that the impact of the policy on mothers and healthcare workers on the ground is not well understood. The harm reduction approach on the level of health policy translates into a complicated, painful moral dilemma for HIV-positive mothers and those offering them guidance on infant feeding. We argue that the underlying socio-economic disparities that continue to fuel the need for a harm reduction policy on infant feeding and the harm to women and children justify: (1) that higher priority be given to solving the infant feeding dilemma with improved data on safe feeding alternatives, and (2) support of innovative, community-driven solutions that address the particular economic and cultural challenges that continue to result in HIV-transmission to children within these communities.

Persistence of genotypic resistance to nelfinavir among women exposed to prophylactic antiretroviral therapy during pregnancy

We assessed the development of drug resistance in women exposed to antiretroviral therapy (ART) for prevention of mother-to-child transmission (PMTCT) after 24 weeks postpartum in a prospective cohort of HIV-1-infected women. HIV-1-infected women, who received prophylactic ART during pregnancy, had genotypic resistance testing performed at the start (T1) of and 24 weeks after ART interruption (T2). The women had CD4 counts >250 cells/ml and no AIDS defining conditions. Of the 30 eligible women, the median age was 27 years [25-75% interquartile range (IQR): 21-32] and the median gestational age of ART initiation was 22 weeks (IQR: 19-27): 19 (63.3%) received zidovudine (ZDV) plus lamivudine (3TC) plus nelfinavir (NFV). At entry, most women (96.7%) were asymptomatic (CDC93 A1/A2), with a median CD4 count of 446 (IQR: 353-686) and median viral load (VL) of 8560 copies/ml (IQR: 3,252-19,515). No HIV-1 vertical transmission was observed. HIV subtype B was the most prevalent (70%). The development of new mutations associated with ART resistance was analyzed at T2. NFV resistance was observed in 4 out of 17 (23.5%) patients exposed to this drug: two major mutations D30N (1/17) and L90M (1/17) and minor mutations (N88S, 2/17). Mutations on positions 44, 69, and 118 (1/28) were present on reverse transcriptase (RT) analysis. No new nonnucleoside reverse transcriptase inhibitor (NNRTI)-associated mutation was observed. In this cohort, ART regimens were very efficient at blocking HIV vertical transmission. However, the high rate of NFV-resistant mutations observed in the postpartum period indicates the need for discussion of ART choices during pregnancy and the potential impact on future therapeutic options for these women. Women previously exposed to ART for PMTCT who will start HIV treatment should have genotypic resistance testing performed.

Population pharmacokinetics of lamivudine in human immunodeficiency virus-exposed and -infected infants

This study aimed to determine lamivudine disposition in infants and to construct an appropriate dose adjustment for age, given the widespread use of lamivudine for both the prevention of mother-to-child transmission of human immunodeficiency virus (HIV) and the treatment of HIV-infected infants. Using a pooled-population approach, the pharmacokinetics of lamivudine in HIV-exposed or -infected infants from four Pediatric AIDS Clinical Trials Group studies were assessed. Ninety-nine infants provided 559 plasma samples for measurement of lamivudine concentrations. All infants received combination antiretroviral therapy including lamivudine dosed at 2 mg/kg of body weight every 12 h (q12h) for the first 4 to 6 weeks of life and at 4 mg/kg q12h thereafter. Lamivudine's apparent clearance was 0.25 liter/h/kg at birth, doubling by 28 days. In the final model, age and weight were the only significant covariates for lamivudine clearance. While lamivudine is predominantly renally eliminated, the serum creatinine level was not an independent covariate in the final model, possibly because it was confounded by age. Inclusion of interoccasion variability for bioavailability improved the individual subject clearance prediction over the age range studies. Simulations based on the final model predicted that by the age of 4 weeks, 90% of infant lamivudine concentrations with the standard 2 mg/kg dose of lamivudine fell below the adult median concentration. This population pharmacokinetic analysis affirms that adjusting the dose of lamivudine from 2 mg/kg to 4 mg/kg q12 h at the age of 4 weeks for infants with normal maturation of renal function will provide optimal lamivudine exposure, potentially contributing to more successful therapy.

Mitochondrial disease in the offspring as a result of antiretroviral therapy

Nucleoside analogue reverse transcriptase inhibitors (NRTIs) have substantially lowered the risk of the mother-to-child transmission of HIV. Evidence of mitochondrial toxicity in vitro, in animal models and in adult HIV-infected patients, has raised concern about the perinatal safety of these antiretrovirals. In zidovudine-exposed, but HIV-uninfected infants, transient anaemia and additional long-term blood abnormalities (neutropenia, thrombopenia and lymphopenia) and hyperlactatemia have been documented. The overall risk of mortality and congenital abnormalities does not appear to be increased, but rare mitochondrial events cannot be excluded for lack of statistical power. French data suggest an above background incidence of mitochondrial symptomatology. Preclinical data demonstrate zidovudine also to be a carcinogen. Long-term systematic follow-up of exposed babies in large cohorts is needed, as are randomised trials with NRTIs carrying a lower risk of mitochondrial toxicity.

Pharmacokinetic modelling of the placental transfer of nelfinavir and its M8 metabolite: a population study using 75 maternal-cord plasma samples

AIMS

A population pharmacokinetic model was developed to characterize the transfer of nelfinavir and its active metabolite M8 from maternal to cord plasma and amniotic fluid.

METHODS

Concentration data were obtained from 75 women on the day of delivery and for whom maternal, umbilical plasma and amniotic fluid samples were collected. Data from 53 pregnant, 61 nonpregnant and seven consecutively pregnant and non pregnant women were then added to the database, the contents of which were analyzed using NONMEM.

RESULTS

Nelfinavir and M8 concentrations in maternal plasma, umbilical plasma and amniotic fluid were described by six connected compartments. Mean (% intersubject variability) population estimates were: absorption rate 00.67 h(-1), lag time 00.87 h, oral clearance and volume of distribution: 39.5 l h(-1) (53%), and 557 l for non pregnant and pregnant women, respectively, and 115 l h(-1) (132%) and 1626 l, respectively, on the day of delivery, M8 formation clearance 0.77 l h(-1) and M8 elimination rate constant 03.41 h(-1) (74%). For nelfinavir and M8, respectively, the mother-to-cord parameters were 0.058 l h(-1) (34%), and 00.35 h(-1) (76%), the cord-to-amniotic fluid rate constants were 0.23 and 00.59 h(-1), and the elimination rate constants from amniotic fluid were 0.36 and 00.49 h(-1). The nelfinavir fetus : maternal concentration ratio was 25% for maternal concentrations between 0.1 and 2.5 mg l(-1), between the 31 and 41st week of gestation.

CONCLUSIONS

The low transfer of nelfinavir from the placenta is unlikely to protect the fetus from vertical HIV-1 transmission.

Use of enhanced perinatal human immunodeficiency virus surveillance methods to assess antiretroviral use and perinatal human immunodeficiency virus transmission in the United States, 1999-2001

OBJECTIVE

Significant reductions in perinatal human immunodeficiency virus (HIV) transmission have been demonstrated in which the HIV-infected mothers and their HIV-exposed infants receive prenatal, intrapartum, and neonatal antiretroviral therapy.

STUDY DESIGN

We used data that were collected through the Enhanced Perinatal Surveillance system for HIV-exposed singleton births that occurred 1999-2001 in 24 sites.

RESULTS

The overall infant infection rate for the 3 years was 4.7%. Compared with zidovudine monotherapy, those patients who received zidovudine with other drugs that included a protease inhibitor and those who received zidovudine and other drugs with no protease inhibitor were less likely to have an infected infant (adjusted odds ratio, 0.4 [95% CI, 0.3-0.07]; adjusted odds ratio, 0.5 [95% CI, 0.3-0.8], respectively).

CONCLUSION

These data support the current treatment recommendations and show that infants were less likely to be infected when the mothers were given a prenatal antiretroviral therapy regimen that contained zidovudine with additional antiretroviral drugs with or without a protease inhibitor in addition to receiving antiretrovirals during delivery and neonatally.

Antiretroviral-associated toxicity among HIV-1-seropositive pregnant women in Mozambique receiving nevirapine-based regimens

OBJECTIVE

To assess toxicities associated with highly active antiretroviral therapy (HAART) among HIV-1-infected pregnant women treated with nevirapine-based regimens according to Mozambican national guidelines.

STUDY DESIGN

Prospective cohort study.

METHODS

HIV-1-infected antiretroviral-naive pregnant women with CD4 counts < or =350 cells/microL were initiated on nevirapine, lamivudine, and stavudine or zidovudine and followed monthly. Severe hepatotoxicity was defined as aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels > or =5-fold the upper limit of normal. Analyses were stratified by baseline CD4 count (<250 vs. 250-350 cells/microL).

RESULTS

Among 146 pregnant women, 75 (52%) began nevirapine, lamivudine, and zidovudine and 71 (48%) began nevirapine, lamivudine, and stavudine. Overall, 79 (54%) women had CD4 counts <250 cells/microL, 7 (5%) had grade II hepatotoxicity, and 4 (3%) had severe (grade III or IV) hepatotoxicity. All 4 women with severe hepatotoxicity had baseline CD4 counts > or =250 cells/microL (P = 0.02). Rates of skin toxicity, anemia, and peripheral neuropathy did not differ by CD4 cell count group. Overall, 12 (8%) women changed or discontinued HAART as a result of drug toxicity.

CONCLUSIONS

Severe hepatotoxicity from nevirapine-containing HAART in this cohort of pregnant women was more common at higher CD4 counts (6% vs. 0% among women with CD4 counts > or =250 cells/microL and CD4 counts <250 cells/microL, respectively), suggesting that laboratory monitoring is necessary when administering nevirapine-containing regimens to pregnant women with CD4 counts > or =250 cells/microL.

Acute human immunodeficiency virus infection in a breast-fed infant in New York City

Acute human immunodeficiency virus (HIV) infection in a breast-fed infant is a rare diagnosis in developed countries. We present a six-month old girl with postnatally acquired HIV infection complicated by Pneumocystis jéroveci pneumonia, cytomegalovirus pneumonitis and encephalopathy. Her mother had tested negative for HIV during pregnancy. Children infected by mothers during an acute seroconversion may have more rapid disease progression.

Characteristics and management of HIV-1-infected pregnant women enrolled in a randomised trial: differences between Europe and the USA

BACKGROUND

Rates of mother-to-child transmission of HIV-1 (MTCT) have historically been lower in European than in American cohort studies, possibly due to differences in population characteristics. The Pediatric AIDS Clinical Trials Group Protocol (PACTG) 316 trial evaluated the effectiveness of the addition of intrapartum/neonatal nevirapine in reducing MTCT in women already receiving antiretroviral prophylaxis. Participation of large numbers of pregnant HIV-infected women from the US and Western Europe enrolling in the same clinical trial provided the opportunity to identify and explore differences in their characteristics and in the use of non-study interventions to reduce MTCT.

METHODS

In this secondary analysis, 1350 women were categorized according to enrollment in centres in the USA (n = 978) or in Europe (n = 372). Factors associated with receipt of highly active antiretroviral therapy and with elective caesarean delivery were identified with logistic regression.

RESULTS

In Europe, women enrolled were more likely to be white and those of black race were mainly born in Sub-Saharan Africa. Women in the US were younger and more likely to have previous pregnancies and miscarriages and a history of sexually transmitted infections. More than 90% of women did not report symptoms of their HIV infection; however, more women from the US had symptoms (8%), compared to women from Europe (4%). Women in the US were less likely to have HIV RNA levels <400 copies/ml at delivery than women enrolling in Europe, and more likely to receive highly active antiretroviral therapy, and to start therapy earlier in pregnancy. The elective caesarean delivery rate in Europe was 61%, significantly higher than that in the US (22%). Overall, 1.48% of infants were infected and there was no significant difference in the rate of transmission between Europe and the US despite the different approaches to treatment and delivery.

CONCLUSION

These findings confirm that there are important historical differences between the HIV-infected pregnant populations in Western Europe and the USA, both in terms of the characteristics of the women and their obstetric and therapeutic management. Although highly active antiretroviral therapy predominates in pregnancy in both settings now, population differences are likely to remain.

TRIAL REGISTRATION

NCT00000869.

HIV

Mother-to-child transmission (MTCT) is almost entirely preventable with a combination of interventions--antiretroviral prophylaxis during pregnancy, intrapartum and neonatally, elective caesarean section and avoidance of breastfeeding. In resource-rich settings new paediatric human immuno-deficiency virus (HIV) infections have reached an all-time low due to broad application of these interventions, particularly the widespread use of highly active antiretroviral therapy and no breastfeeding. However, most HIV-infected pregnant women live in developing countries where <10% of them have access to preventative interventions. Although MTCT rates in developed countries are now around 1-2%, rates in developing countries remain very much higher. Although the vast majority of infants born to HIV-infected mothers can thus be protected from acquisition of infection, they would then be exposed to antiretroviral drugs for which there is only limited information on toxicity and long-term safety. However, based on current knowledge, the immense benefits of antiretroviral prophylaxis in reducing MTCT risk far outweigh the potential for adverse effects.

Clinically Significant Anemia in HIV-Infected Pregnant Women in India Is Not a Major Barrier to Zidovudine Use for Prevention of Maternal-to-Child Transmission

OBJECTIVES

To determine the prevalence of anemia (serum hemoglobin <10 g/dL) and assess zidovudine use and toxicity in HIV-positive pregnant women in India.

METHODS

From 2002 through 2006, 24,105 pregnant women in Pune were screened for HIV and anemia. As part of an infant prevention of mother-to-child transmission (PMTCT) trial, enrolled HIV-positive women (n = 467) were assessed for anemia and associated outcomes, comparing women receiving zidovudine for >or=2 weeks versus no zidovudine.

RESULTS

The prevalence of anemia was 38.7% in HIV-positive women. Anemic women were as likely as nonanemic women to receive zidovudine. At delivery, regardless of anemia status at enrollment, women receiving >or=2 weeks of zidovudine were 70% less likely to be anemic compared with women receiving no zidovudine (odds ratio = 0.28, 95% confidence interval: 0.14 to 0.57; P < 0.01), received iron and folic acid supplements for longer periods, and had no increased adverse delivery or newborn birth outcomes.

CONCLUSIONS

A significant proportion of HIV-positive pregnant women in India present for antenatal care with anemia. With concurrent iron and folic acid supplementation, however, zidovudine use is not associated with persistent or worsening anemia or associated adverse outcomes. In Indian community settings, all pregnant HIV-positive women should receive early anemia treatment. Mild anemia should not limit zidovudine use for PMTCT in India.

Characterization of the main placental cytokine profiles from HIV-1-infected pregnant women treated with anti-retroviral drugs in France

Cytokines are involved in regulating HIV-1 infection. They are also placental environment major components. We assessed the potential impact of HIV-1 infection and/or anti-retroviral drugs on the placental cytokine profiles that may be involved in controlling HIV-1 placental dissemination. Placental explants were obtained after elective caesarean section from anti-retroviral-treated HIV-1-infected pregnant women and from HIV-1 non-infected pregnant women. The main placental cytokines were assessed for protein secretion in the supernatants of 24-h placental culture explants and/or in uncultured placental explants for mRNA expression levels. The cytokine profiles were different between the HIV-1-infected and the non-infected groups. Higher medians of leukaemia inhibiting factor (LIF), tumour necrosis factor (TNF)-alpha and interleukin (IL)-8 secretion were found in the 24-h culture supernatant of term placenta from HIV-1-infected women. High median levels of IL-16 and regulated upon activation normal T cell expressed and secreted (RANTES) levels were found in both groups. The mRNA expression medians were lower for TNF-alpha and IL-8 and higher for stromal cell-derived factor-1 (SDF-1) in uncultured placental explants from HIV-1-infected women. In the HIV-1-infected group, but not in the non-infected group, the secretion levels of TNF-alpha and IL-8, as well as their mRNA expression levels, were highly positively correlated; furthermore, their secretion levels were correlated positively with LIF and IL-10 secretion levels. We found no correlation between the cytokine levels and the immunovirological status of the HIV-1-infected mothers or the type or duration of treatment. These results highlight the potential impact of HIV-1 and of the anti-retroviral treatments on the placental cytokines pattern, independently of their anti-viral activity.

Twin pregnancy as a risk factor for mother-to-child transmission of HIV-1: trends over 20 years

OBJECTIVE

We investigated whether twin pregnancies were at increased risk of mother-to-child HIV-1 transmission (MTCT), in comparison with singletons.

METHODS

Among HIV-1 infected women enrolled in the French Perinatal HIV Cohort (n = 9262), we studied the association between twin deliveries and MTCT rate according to three time periods (pre-1994, 1994-1996, 1997-2004) and the effect of birth order. The mother was considered to have transmitted if at least one of the twins was infected. Univariate and multivariate analyses of risk factors for MTCT were performed for deliveries in the periods up to 1996.

RESULTS

Overall, 2.1% (192/9262) of all the deliveries were twins. The rate of prematurity was greater in twins than in singletons (54% and 13%, respectively). Up to 1996 the rate of MTCT of HIV-1 was 28.3% (15/53) in twin pregnancies, versus 13.5% (414/3077) in singletons [odds ratio (OR), 2.5; 95% confidence interval (CI), 1.4-4.7; P = 0.002; adjusted OR, 2.3: 95% CI, 1.1-2.3; P = 0.03). In the period from 1997 to 2003, MTCT was low and did not differ between twins (1.0%) and singletons (1.8%; P = 1.0). Overall, the transmission rate for the first-born child was threefold that for the second-born child (14/164, 8.5% versus 4/164, 2.4%; P = 0.008).

CONCLUSION

Twin pregnancies were at increased risk of transmission, but in the era of HAART this risk was reduced for twins, as well as singletons. Management of multiple pregnancies should take into account the risks of premature rupture of the membranes and preterm delivery.

Hematologic Effects of Maternal Antiretroviral Therapy and Transmission Prophylaxis in HIV-1-Exposed Uninfected Newborn Infants

OBJECTIVE

A prospective observational study to investigate hematologic alterations during the first 3 months of life in HIV-exposed uninfected infants subjected to antiretroviral medication before and after birth.

METHODS

Two hundred twenty-one consecutive uninfected infants born to HIV-positive mothers on antiretroviral medication during pregnancy were included. Perinatal transmission prophylaxis comprised zidovudine (ZDV) administered intravenously intrapartum and 10 days after birth. Blood counts and differentials were determined at birth and at 2, 4, 6, and 12 weeks of age, and hematologic toxicity was graded according to pediatric toxicity scales. Data were analyzed according to the kind of prenatal medication (ZDV alone or with another nucleoside reverse transcriptase inhibitor [NRTI] vs. highly active antiretroviral therapy [HAART]).

RESULTS

Median hemoglobin was significantly lower in HAART-exposed newborns from birth (P = 0.004) until day 28. During follow-up, 119 (53.8%) infants had anemia grade 2 or higher on at least 1 occasion; 16 (7.2%) received red blood cell transfusion at 23 (range: 1-56) days of age. Neutropenia grade 2 or higher occurred in 106 (48.0%) infants at least once; 8 infants had staphylococcal infections, and 2 infections were severe. After adjustment for possible confounders (prematurity, birth weight, ethnicity, gender, duration of maternal antiretroviral therapy, maternal Centers for Disease Control and Prevention stage, and maternal illicit drug use), HAART exposure was the only independent risk factor for anemia (odds ratio [OR] = 2.22, 95% confidence interval [CI]: 1.06 to 4.64; P = 0.034) and neutropenia (OR = 2.15, CI: 1.02 to 4.55; P = 0.045).

CONCLUSIONS

Antiretroviral transmission prophylaxis is associated with significant anemia and neutropenia in HIV-uninfected infants during the first 3 months of life. Anemia was more profound in HAART-exposed infants.

Factors related to medical appointment attendance after childbirth among HIV-infected women in the Paris region

This study examined factors related to medical appointment attendance after childbirth among HIV-infected women in the Paris region. We hypothesized that despite regular utilization of prenatal care, many women may not attend medical appointments after delivery for their own HIV infection. This was an observational cohort study of HIV-seropositive women delivering in four Paris hospitals in 2001. Follow-up attendance through 24 months after delivery was defined as 'regular' for women who had > or =4 HIV visits during the period, 'irregular' for <4 visits in the 24-months period and/or a gap between two visits >12 months, and 'no attendance' when < or =1 visit in the 2-year period. Of 169 women enrolled, 125 (75%) had regular attendance, 24 (14%) had irregular attendance, and 18 (11%) had no attendance. Multivariate analysis found the greater number of HIV visits during pregnancy and the prescription of combination therapy (versus zidovudine monotherapy) during pregnancy to be significantly related to regular attendance. Of the 18 women who had no attendance, 8 women (47%) continued to attend regular paediatric appointments with their infants during the 24-month period. Scheduling more frequent HIV visits during pregnancy may establish a pattern that will improve attendance during the post-partum period. In addition, increased communication between the health care providers of the mother and child may increase appointment attendance following delivery.

Declines in low birth weight and preterm birth among infants who were born to HIV-infected women during an era of increased use of maternal antiretroviral drugs: Pediatric Spectrum of HIV Disease, 1989-2004

OBJECTIVE

Our goal was to determine trends in low birth weight and preterm birth among US infants born to HIV-infected women.

METHODS

We used data from the longitudinal Pediatric Spectrum of HIV Disease, a large HIV cohort, to assess trends in low birth weight and preterm birth from 1989 to 2004 among 11,321 study infants. Among women with prenatal care, we also assessed risk factors, including maternal antiretroviral therapy during pregnancy, that were predictive of low birth weight and preterm birth using univariate and multivariate logistic regression models.

RESULTS

Overall, 11,231 of 14,464 infants who were enrolled in Pediatric Spectrum of HIV Disease were tested during the neonatal period. From 1989 to 2004, testing increased from 32% to 97%. The proportion of HIV-exposed infants who had low birth weight decreased from 35% to 21% and occurred in all racial/ethnic groups. Prevalence of preterm birth decreased from 35% to 22% and occurred in all groups. Any maternal antiretroviral therapy use increased from 2% to 84%. Among 8793 women who had prenatal care, low birth weight was associated with a history of illicit maternal drug use, unknown maternal HIV status before delivery, symptomatic maternal HIV disease, black race, Hispanic ethnicity, and infant HIV infection. Antiretroviral therapy or lack of it was not associated with low birth weight. Among women with prenatal care, preterm birth was associated with a history of illicit maternal drug use, symptomatic maternal HIV disease, no antiretroviral therapy, receipt of a 3-drug highly active antiretroviral therapy regimen with protease inhibitors, black race, and infant HIV infection.

CONCLUSIONS

The proportion of infants who had low birth weight or were born preterm declined during an era of increased maternal antiretroviral therapies. These Pediatric Spectrum of HIV Disease trends differ from the overall increases in both outcomes among the US population.

Frequency of Hprt mutant lymphocytes and micronucleated erythrocytes in p53-haplodeficient mice treated perinatally with AZT and AZT in combination with 3TC

Azidothymidine (AZT) is a nucleoside reverse transcriptase inhibitor (NRTI) that is used for reducing mother-to-child transmission of human immunodeficiency virus I. Combinations of AZT and 3'-thiacytidine (3TC) are even more effective than AZT alone. AZT, however, is a mutagen and carcinogen in rodent models and 3TC can increase the genotoxicity of AZT. Since p53 plays a key role in human and mouse tumorigenesis, p53-haplodeficient mice are currently being evaluated as a model for assessing the carcinogenicity of perinatal exposure to NRTIs. In the present study, male C57BL/6 p53(+/+) and p53(-/-) mice were mated with C3H p53(+/+) females; the pregnant females were treated on gestation day 12 through parturition with 40, 80, and 160 mg/kg of AZT or a combination of 160 mg/kg AZT and 100 mg/kg 3TC (AZT-3TC); the p53(+/+) and p53(+/-) offspring were treated daily after birth through postnatal day (PND) 28. The frequencies of micronucleated reticulocytes (MN-RETs) and micronucleated normochromatic erythrocytes (MN-NCEs) were determined on PND1, PND10, and PND28; the frequency of Hprt mutant lymphocytes was measured on PND28. The frequencies of MN-RETs and MN-NCEs were increased in treated animals at all time points; there were no differences in the responses of p53(+/+) and p53(+/-) animals treated with identical doses of NRTIs. After correction for clonal expansion, both AZT and AZT-3TC treatments induced small but significant increases in the frequency of Hprt mutant lymphocytes in p53(+/-) mice, but not in p53(+/+) mice. The data indicate that p53 haplodeficiency affects the genotoxicity of NRTIs; thus, p53(+/-) mice may be a sensitive model for evaluating the carcinogenicity of perinatal exposure to NRTIs.

Clinical mitochondrial dysfunction in uninfected children born to HIV-infected mothers following perinatal exposure to nucleoside analogues

Clinical and biological observations of mitochondrial dysfunction in children exposed to zidovudine (azidothymidine, AZT) during the perinatal period rapidly followed similar observations in animal experiments. To date, two different disorders have been identified. The first, asymptomatic hyperlactatemia, is observed during treatment in one third of exposed newborns, and is reversible with treatment cessation. In rare cases, it is associated with symptomatic acidosis. Regression may be slow, taking up to several months after the end of the treatment. The long-term clinical consequences of this biochemical disturbance are unknown. The second disorder involves severe neurological symptoms, which become clinically detectable during the first 2 years of life. These symptoms are associated with a series of biochemical and ultrastructural changes consistent with persistent mitochondrial dysfunction. This latter phenomenon is rare, and affects only 0.3-0.5% of exposed children in the French pediatric cohort, in which observations continue. Despite initial controversy, several similar observations in other cohorts have since confirmed its occurrence. The pathophysiology of these two mitochondrial dysfunctions may differ. Continued efforts to identify and understand clinical mitochondrial toxicities are essential, given the intensification and diversification of perinatal prophylaxis strategies, and the number of pregnant women potentially involved.

Use of antiretroviral therapy in pregnant HIV-infected women and the risk of premature delivery: a meta-analysis

BACKGROUND

The use of antiretroviral agents in pregnant HIV-infected women has been reported to increase the risk of premature delivery in some studies. We performed a meta-analysis on relevant studies to address this question.

METHODS

We searched Medline, Embase and the Cochrane Controlled Clinical Trials Register for English language articles. Studies that reported premature delivery for HIV-infected women treated with antiretroviral regimens during pregnancy were selected. Meta-analyses were performed using a random effects model.

RESULTS

Thirteen prospective cohorts and one retrospective study met the inclusion criteria. Antiretroviral therapy during pregnancy did not increase the risk of premature delivery overall [odds ratio (OR) 1.01, 95% confidence interval (CI) 0.76-1.34]. In subgroup analyses, compared with no therapy, monotherapy (mostly zidovudine) conferred an OR of 0.86 (95% CI 0.73-1.01), whereas combination therapy conferred an OR of 1.13 (95% CI 0.79-1.63). The use of protease inhibitor (PI)-containing combinations resulted in an OR for premature delivery of 1.24 (95% CI 0.76-2.02), compared with combinations without PI. The initiation of combination therapy before pregnancy or in the first trimester resulted in an OR of 1.71 (95% CI 1.09-2.67) compared with therapy initiation in the second trimester and beyond. There was a large degree of heterogeneity between studies.

CONCLUSION

Evidence indicates that antiretroviral therapy during pregnancy is not associated with an overall increased risk of premature delivery. The use of combination regimens before or early in pregnancy may slightly increase the risk of prematurity. Continued surveillance will be necessary to quantify such a risk accurately.

Time Trends for HIV-1 Antiretroviral Resistance Among Antiretroviral-Experienced and Naive Pregnant Women in New York City During 1991 to Early 2001

Time trends in the prevalence of drug resistance to antiretroviral therapy (ART) in pregnant women have not been studied. Treatment and prophylactic efficacy could be compromised by drug-resistant HIV strains. We conducted a repeated cross-sectional study of antiretroviral resistance mutations to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) and of major mutations to protease inhibitors (PIs) in virus isolates from 300 HIV-infected pregnant women in New York City from 1991 to early 2001. The overall prevalence of mutations for NRTIs from 1991 to early 2001 was higher for ART-experienced (25.6% [95% confidence interval (CI): 19.1% to 32.1%]) than ART-naive (8.6% [95% CI: 3.7% to 13.4%]) mothers (P < 0.002). For NNRTIs, the overall prevalence of mutations was somewhat higher among ART-experienced (5.8% [95% CI: 2.3% to 9.3%]) versus ART-naive (1.6% [95% CI: 0% to 3.7%]) women (P = 0.06), and increased over time for ART-naive women (0%-7.4%; P = 0.03) and ART-experienced women (0%-19.4%; P = 0.0002). The prevalence of PI-associated mutations was also higher overall among ART-experienced mothers (5.8% [95% CI: 2.3% to 9.3%] vs. 1.6% [95% CI: 0% to 3.7%]; P = 0.06), with increases over time seen for ART-naive women (0%-7.4%; P = 0.03) and ART-experienced women (0%-16.1%; P = 0.0008). The increasing prevalence of drug resistance in pregnant women, including those who are drug-naive, underscores the necessity for resistance testing to guide treatment to achieve suppression of the mother's virus.

AIDS in pregnancy, part II: Treatment in the era of highly active antiretroviral therapy and management of obstetric, anesthetic, and pediatric issues

International guidelines recommend resistance testing of maternal virus for all human immunodeficiency virus (HIV)-infected pregnant women. The use of highly active antiretroviral therapy leads to maximal virologic suppression, thus minimizing the risk of drug resistance, but it is available only in developed countries. In developing countries, the use of short-course regimens is becoming more widespread. Women infected with HIV may be at greater risk for complications during pregnancy, including ectopic pregnancy, early abortions, bacterial pneumonia, urinary tract infection, oral and recurrent vaginal thrush, malaria, and tuberculosis. Regional anesthesia is often the treatment of choice when administering anesthesia in an HIV-infected pregnant woman. Infected children present decreased survival rates, while uninfected children born to infected mothers present a higher incidence of poor weight gain, short stature, and wasting than would be expected for the general population. Transmission of HIV-1 can occur via breast-feeding.

Antiretrovirals for reducing the risk of mother-to-child transmission of HIV infection

BACKGROUND

Antiretroviral drugs (ARV) reduce viral replication and can reduce mother-to-child transmission of HIV either by lowing plasma viral load in pregnant women or through post-exposure prophylaxis in their newborns. In rich countries, highly active antiretroviral therapy (HAART) has reduced the vertical transmission rates to around 1-2%, but HAART is not yet widely available in low and middle income countries. In these countries, various simpler and less costly antiretroviral regimens have been offered to pregnant women or to their newborn babies, or to both.

OBJECTIVES

To determine whether, and to what extent, antiretroviral regimens aimed at decreasing the risk of mother-to-child transmission of HIV infection achieve a clinically useful decrease in transmission risk, and what effect these interventions have on maternal and infant mortality and morbidity.

SEARCH STRATEGY

We sought to identify all relevant studies regardless of language or publication status by searching the Cochrane HIV/AIDS Review Group Trials Register, The Cochrane Library, Medline, EMBASE and AIDSearch and relevant conference abstracts. We also contacted research organizations and experts in the field for unpublished and ongoing studies. The original review search strategy was updated in 2006.

SELECTION CRITERIA

Randomised controlled trials of any antiretroviral regimen aimed at decreasing the risk of mother-to-child transmission of HIV infection compared with placebo or no treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently selected relevant studies, extracted data and assessed trial quality. For the primary outcomes, we used survival analysis to estimate the probability of infants being infected with HIV (the observed proportion) at various specific time-points and calculated efficacy at a specific time as the relative reduction in the proportion infected. Efficacy, at a specific time, is defined as the preventive fraction in the exposed group compared to the reference group, which is the relative reduction in the proportion infected: 1-(Re/Rf). For those studies where efficacy and hence confidence intervals were not calculated, we calculated the approximate confidence intervals for the efficacy using recommended methods. For analysis of results that are not based on survival analyses we present the relative risk for each trial outcome based on the number randomised. No meta-analysis was conducted as no trial assessed the identical drug regimens.

MAIN RESULTS

Eighteen trials including 14,398 participants conducted in 16 countries were eligible for inclusion in the review. The first trial began in April 1991 and assessed zidovudine (ZDV) versus placebo and since then, the type, dosage and duration of drugs to be compared has been modified in each subsequent trial. Antiretrovirals versus placebo In breastfeeding populations, three trials found that:ZDV given to mothers from 36 to 38 weeks gestation, during labour and for 7 days after delivery significantly reduced HIV infection at 4-8 weeks (Efficacy 32.00%; 95% CI 0.64 to 63.36), 3 to 4 months (Efficacy 34.00%; 95% CI 6.56 to 61.44), 6 months (Efficacy 35.00%; 95% CI 9.52 to 60.48), 12 months (Efficacy 34.00%; 95% CI 8.52 to 59.48) and 18 months (Efficacy 30.00%; 95% CI 2.56 to 57.44).ZDV given to mothers from 36 weeks gestation and during labour significantly reduced HIV infection at 4 to 8 weeks (Efficacy 44.00%; 95% CI 8.72 to 79.28) and 3 to 4 months (Efficacy 37.00%; 95% CI 3.68 to 70.32) but not at birth.ZDV plus lamivudine (3TC) given to mothers from 36 weeks gestation, during labour and for 7 days after delivery and to babies for the first 7 days of life (PETRA 'regimen A') significantly reduced HIV infection (Efficacy 63.00%; 95% CI 41.44 to 84.56) and a combined endpoint of HIV infection or death (Efficacy 61.00%; 95% CI 41.40 to 80.60) at 4 to 8 weeks but these effects were not sustained at 18 months.ZDV plus 3TC given to mothers from the start of labour until 7 days after delivery and to babies for the first 7 days of life (PETRA 'regimen B') significantly reduced HIV infection (Efficacy 42.00%; 95% CI 12.60 to 71.40) and HIV infection or death at 4 to 8 weeks (Efficacy 36.00%; 95% CI 8.56 to 63.44) but the effects were not sustained at 18 months.ZDV plus 3TC given to mothers during labour only (PETRA 'regimen C') with no treatment to babies did not reduce the risk of HIV infection at either 4 to 8 weeks or 18 months. In non-breastfeeding populations, three trials found that:ZDV given to mothers from 14 to 34 weeks gestation and during labour and to babies for the first 6 weeks of life significantly reduced HIV infection in babies at 18 months (Efficacy 66.00%; 95% CI 34.64 to 97.36).ZDV given to mothers from 36 weeks gestation and during labour with no treatment to babies ('Thai-CDC regimen') significantly reduced HIV infection at 4 to 8 weeks (Efficacy 50.00%; 95% CI 12.76 to 87.24) but not at birthZDV given to mothers from 38 weeks gestation and during labour with no treatment to babies did not influence HIV transmission at 6 months. Longer versus shorter regimens using the same antiretrovirals One trial in a breastfeeding population found that:ZDV given to mothers during labour and to their babies for the first 3 days of life compared with ZDV given to mothers from 36 weeks and during labour (similar to 'Thai-CDC') resulted in HIV infection rates that were not significantly different at birth, 4-8 weeks, 3 to 4 months, 6 months and 12 months. Three trials in non-breastfeeding populations found that:ZDV given to mothers from 28 weeks gestation during labour and to infants for the first 3 days after birth compared with ZDV given to mothers from 35 weeks gestation through labour and to infants from birth to 6 weeks significantly reduced HIV infection rate at 6 months (Efficacy 45.00%; 95% CI 1.88 to 88.12) but compared with the same regimen ZDV given to mothers from 28 weeks gestation through labour and to infants from birth to 6 weeks did not result in a statistically significant difference in HIV infection at 6 months. ZDV given to mothers from 35 weeks gestation during labour and to infants for the first 3 days after birth was considered ineffective for reducing transmission rates and this regimen was discontinued.An antenatal/intrapartum course of ZDV used for a median of 76 days compared with an antenatal/intrapartum ZDV regimen used for a median 28 days with no treatment to babies in either group did not result in HIV infection rates that were significantly different at birth and at 3 to 4 months. In a programme where mothers were routinely receiving ZDV in the third trimester of pregnancy and babies were receiving one week of ZDV therapy, a single dose of nevirapine (NVP) given to mothers in labour and to their babies soon after birth compared with a single dose of NVP given to mothers only resulted in HIV infection rates that were not significantly different at birth and 6 months. However the reduction in risk of HIV infection or death at 6 months was marginally significant (Efficacy 45.00%; 95% CI -4.00 to 94.00). Antiretroviral regimens using different drugs and durations of treatment In breastfeeding populations, three trials found that:A single dose of NVP given to mothers at the onset of labour plus a single dose of NVP given to their babies immediately after birth ('HIVNET 012 regimen') compared with ZDV given to mothers during labour and to their babies for a week after birth resulted in lower HIV infection rates at 4-8 weeks (Efficacy 41.00%; 95% CI 11.60 to 70.40), 3-4 months (Efficacy 39.00%; 95% CI 11.56 to 66.44), 12 months (Efficacy 36.00%; 95% CI 8.56 to 63.44) and 18 months (Efficacy 39.00%; 95% CI 13.52 to 64.48). In addition, the NVP regimen significantly reduced the risk of HIV infection or death at 4-8 weeks (Efficacy 42.00%; 95% CI 14.56 to 69.44), 3 to 4 months (Efficacy 40.00%; 95% CI 14.52 to 65.48), 12 months (Efficacy 32.00%; 95% CI 8.48 to 55.52) and 18 months (Efficacy 33.00%; 95% CI 9.48 to 56.52). The 'HIVNET 012 regimen' plus ZDV given to babies for 1 week after birth compared with the 'HIVNET 012 regimen' alone did not result in a statistically significant difference in HIV infection at 4 to 8 weeks.A single dose of NVP given to babies immediately after birth plus ZDV given to babies for 1 week after birth compared with a single dose of NVP given to babies only significantly reduced the HIV infection rate at 4 to 8 weeks (Efficacy 37.00%; 95% CI 3.68 to 70.32). Five trials in non-breastfeeding populations found that:In a population in which mothers were receiving 'standard' ARV for HIV infection a single dose of NVP given to mothers in labour plus a single dose of NVP given to babies immediately after birth ('HIVNET 012 regimen') compared with placebo did not result in a statistically significant difference in HIV infection rates at birth and at 4 to 8 weeks. The 'Thai CDC regimen' compared with the 'HIVNET 012 regimen' did not result in a significant difference in HIV infection at 4 to 8 weeks.A single dose of NVP given to babies immediately after birth compared to ZDV given to babies for the first 6 weeks of life did not result in a significant difference in HIV infection rates at 4-8 weeks and 3 to 4 months.ZDV plus 3TC given to mothers in labour and for a week after delivery and to their infants for a week after birth (similar to 'PETRA regimen B') compared with NVP given to mothers in labour and immediately after delivery plus a single dose of NVP to their babies immediately after birth (similar to 'HIVNET 012 regimen') did not result in a significant difference in the HIV infection rate at 4 to 8 weeks. (ABSTRACT TRUNCATED)

[New challenges in therapeutic management of human immunodeficiency virus-infected children]

More than 2 millions of children worldwide are HIV-infected. Recently, the HIV related mortality and morbidity has dramatically decreased due to the use of antiretroviral multitherapies in the HIV-infected children. However the therapeutic management of HIV-infected children is complex and may be complicated by socio-familial issues. Short and long term toxicity of antiretrovirals but also of HIV itself are of concern. Despite the good clinical and immunological results of antiretroviral multitherapies, virological failure may occur. Paediatric pharmacokinetic specificities and inadequate galenic presentation of drugs could lead to virological failure. However, the use of more potent drugs with more adapted presentation actually reduces this risk of failure. Prospective cohorts of HIV-infected children and new antiretroviral drugs paediatric evaluation are of key importance and can improve the paediatric therapeutic management. Finally, universal access to antiretroviral drugs in children, particularly in developing countries is the major actual and future challenge.

Drug resistance among HIV-infected pregnant women receiving antiretrovirals for prophylaxis

OBJECTIVE

To quantify primary resistance mutations (PRMs) among HIV-1-infected women receiving antiretroviral therapy (ART) for prevention of mother-to-child transmission (MTCT).

METHODS

Peripheral blood mononuclear cell samples from HIV-1-infected women enrolled in a prospective cohort study in Argentina, the Bahamas, Brazil, and Mexico (NISDI Perinatal Study) were assayed for PRMs. Eligible women were those enrolled by March 2005 and diagnosed with HIV-1 infection during the current pregnancy, and who received ART for MTCT prophylaxis and were followed for 6-12 weeks postpartum.

RESULTS

Of 819 women, 198 met the eligibility criteria. At enrollment, 98% were asymptomatic, 62% had plasma viral load < 1000 copies/ml, 53% had CD4+ cell count > or = 500 cells/microl, and 78% were ART-exposed (mean duration, 8.0 weeks; 95% confidence interval, 7.1-8.9). The most complex ART regimen during pregnancy was usually (81%) a three-drug regimen [two nucleoside reverse transcriptase inhibitors (NRTIs) + one protease inhibitor or two NRTIs + one non-nucleoside reverse transcriptase inhibitor). PRMs were observed in samples from 19 (16%) of 118 women that were amplifiable at one or both time points [11/76 (14%) at enrollment; 14/97 (14%) at 6-12 weeks]. The occurrence of PRMs was not associated with clinical, immunological, or virological disease stage at either time point, whether ART-naive versus exposed at enrollment, or the most complex or number of antiretroviral drug regimens received during pregnancy (P > 0.1). Of 55 women with amplifiable samples at both time points, PRMs were detected in 11 samples (20%).

CONCLUSIONS

PRMs occurred among 16.1% of relatively healthy HIV-1-infected mothers from Latin American and Caribbean countries receiving MTCT prophylaxis.

A liquid chromatography/atmospheric pressure ionization tandem mass spectrometry quantitation method for nevirapine and its two oxidative metabolites, 2-hydroxynevirapine and nevirapine 4-carboxylic acid, and pharmacokinetics in baboons

A rapid highly sensitive and specific electrospray ionization (ESI) liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for quantification of nevirapine (NVP) and its two metabolites, 2-hydroxynevirapine (2-OHNVP) and nevirapine 4-carboxylic acid (4-CANVP), in baboon serum was developed and validated. Nevirapine, 2-OHNVP, 4-CANVP, and the internal standard, hesperetin, were extracted from baboon serum with ethyl acetate. Components in the extract were separated on a 50 x 2.1 mm Aquasil C(18) 5 microm stainless steel column by isocratic elution with 40% acetonitrile/0.1% formic acid at a flow rate of 0.2 mL/min. The liquid flow was passed through a pre-source splitter and 5% of the eluant was introduced into the atmospheric pressure ionization (API) source. The components were analyzed in the multiple-reaction monitoring (MRM) mode as the precursor/product ion pair of m/z 267.2/226.2 for NVP, 283.0/161.2 for 2-OHNVP, 297.2/279.2 for 4-CANVP, and 303.2/177.2 for hesperetin. Linear calibration curves were obtained in the range of 1-1000 ng/mL for NVP and 2-OHNVP and 5-1000 ng/mL for 4-CANVP, using 0.2 mL baboon serum, respectively. The within-day and between-day precisions were <10% for NVP and 2-OHNVP, and <11.5% for 4-CANVP. Due to the similar structures and fragmentation patterns of 2-OHNVP and 3-OHNVP, it is not expected that the LC/MS/MS can differentiate 2-OHNVP and 3-OHNVP and they were assayed as a composite. The method was applied to a single-dose escalation study of NVP in non-pregnant baboons (Papio anubis) to characterize the pharmacokinetics of NVP, 2-OHNVP plus 3-OHNVP, and 4-CANVP, and to determine the appropriate dose necessary to achieve comparable peak serum concentration of NVP as reported in healthy human adults.