Marianne Burgard

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.

Natural history of serum HIV-1 RNA levels in 330 patients with a known date of infection.

ObjectiveTo describe the spontaneous course, before the introduction of highly active antiretroviral therapy (HAART), of HIV-1 RNA during the AIDS-free period of the disease. To assess the predictive value of changes in HIV-1 RNA levels. DesignA total of 330 patients with a known date of infection followed in the SEROCO cohort. MethodsHIV-1 RNA levels (threshold, 200 copies/ml) were evaluated from 2243 frozen sera obtained from enrolment until the onset of AIDS or until February 1996. Lowess curves were used to describe the variations of viraemia during follow-up. A Cox regression model was used to assess the predictive value of early and updated CD4 cell count and viral load. ResultsIn addition to a lower early viral load, patients who remained AIDS-free had, on average, a longer period of viral load decrease after infection (36 versus 18 months), followed by a slower viral load increase compared with those who progressed to AIDS. A true plateau-phase after the seroconversion period, lasting approximately 4 years, was identified only in patients who remained AIDS-free for at least 90 months. In multivariate analysis, both early viral load and later changes were significant predictors of progression to AIDS. A decrease in the CD4 cell count to less than 200 cells/μl and the onset of a group B condition remained significant predictors of progression. ConclusionOur study extends to the early post-seroconversion phase the prognostic value of extracellular HIV-1 RNA levels. Moreover, our data suggest that, in most HIV-infected individuals, a progressive loss of control of viral replication arises during the early years of HIV-1 infection.

Impact of 5 years of maximally successful highly active antiretroviral therapy on CD4 cell count and HIV-1 DNA level.

Objectives: To evaluate the impact on CD4 cell count and HIV-1 DNA level in peripheral blood mononuclear cells (PBMC) of long-term highly active antiretroviral therapy (HAART) in the setting of maximal success, i.e., constant plasma HIV-1 RNA load suppression. Design: Retrospective analysis of patients selected for a constantly undetectable plasma HIV-1 RNA load since HAART initiation. Methods: HIV-1 DNA was measured in PBMC using a real-time polymerase chain reaction assay. Loess estimates and regression analysis were used for modelling the variations of the CD4 cell count and HIV DNA level over time. Results: The study included 41 patients chronically infected with HIV-1 who had been taking HAART for a median duration of 60.4 months and had an undetectable plasma HIV RNA load ever since the first 6 months of HAART; 25 were tested for HIV-1 DNA. The mean CD4 cell count increase was high during the first 18 months on therapy (168 × 106 cells/l per year), much lower afterwards (38 × 106 cells/l per year), independently of the baseline CD4 cell count. Most of the patients (73.2%) reached a CD4 cell count constantly ⩾ 400 × 106/l during follow-up. HIV-1 DNA showed a mean decrease of 0.48 log10 copies/106 PBMC during the first year, of 0.18 log10 copies/106 PBMC per year during the 2nd and 3rd years, but no significant decrease afterwards. Conclusions: These results question the benefit of very long-term maintenance of HAART in terms of CD4 gain and HIV-1 DNA reduction.

Impact of Hiv-1 Genetic Diversity on Plasma Hiv-1 Rna Quantification: Usefulness of the Agence Nationale de Recherches sur le Sida Second-generation Long Terminal Repeat-based Real-time Reverse Transcriptase Polymerase Chain Reaction Test

The high genetic diversity of HIV-1 has a major impact on the quantification of plasma HIV-1 RNA, representing an increasingly difficult challenge. A total of 898 plasma specimens positive for HIV-1 RNA by commercial assays (Amplicor v1.5; Roche Diagnostic Systems, Alameda, CA or Versant v3.0; Bayer Diagnostics, Emeryville, CA) were tested using the Agence Nationale de Recherches sur le SIDA second-generation (G2) real-time reverse transcriptase polymerase chain reaction (RT-PCR) test: 518 samples containing HIV-1 of known subtype, including 88 from 2 subtype panels and 430 harboring B (n = 266) and non-B (n = 164) group M HIV-1 subtypes from patients followed up in 2002 through 2005 at Necker Hospital (Paris, France), and 380 samples from 10 different countries (Argentina, Cambodia, Cameroon, Central African Republic, France, Ivory Coast, Madagascar, Morocco, Thailand, and Zimbabwe). HIV-1 RNA values obtained by G2 real-time PCR were highly correlated with those obtained by the Amplicor v1.5 for B and non-B subtypes (R2 = 0.892 and 0.892, respectively) and for samples from diverse countries (R2 = 0.867 and 0.893 for real-time PCR vs. Amplicor v1.5 and real-time PCR vs. Versant v3.0, respectively). Approximately 30% of specimens harboring non-B subtypes were underquantified by at least −0.51 log10 in Amplicor v1.5 versus 5% underquantified in G2 real-time PCR. Discrepant results were also obtained with subtype B samples (14% underquantified by Amplicor v1.5 vs. 7% by G2 real-time PCR). Similar percentages were observed when comparing results obtained with the G2 real-time PCR assay with those obtained using the Versant assay. Addressing HIV-1 diversity, continual monitoring of HIV-1 RNA assays, together with molecular epidemiology studies, is required to improve the accuracy of all HIV RNA assays.

Early Levels of HIV-1 DNA in Peripheral Blood Mononuclear Cells Are Predictive of Disease Progression Independently of HIV-1 RNA Levels and CD4+ T Cell Counts

BACKGROUND The objective of this work was to assess the role of human immunodeficiency virus (HIV) reservoirs in the risk of disease progression, by studying the relationship between HIV DNA level in peripheral blood mononuclear cells (PBMCs) and progression toward acquired immunodeficiency syndrome (AIDS). METHODS HIV-1 DNA levels in PBMCs were determined by quantitative polymerase chain reaction for 383 patients enrolled in the SEROCO Cohort Study who had experienced seroconversion and had been followed up for >8 years. We compared the predictive values of HIV DNA level, HIV RNA level, and CD4+ cell count. RESULTS Between 6 and 24 months after seroconversion, HIV DNA level was a major predictor of progression to AIDS independently of HIV RNA level and CD4+ T cell count (adjusted relative risk [RR] for a 1-log(10) increase, 3.20 [95% confidence interval {CI}, 1.70-6.00]). HIV DNA level was also a major predictor of disease progression during the first 6 months after seroconversion (adjusted RR, 4.16 [95% CI, 1.70-10.21]), when HIV RNA level and CD4+ T cell count were less predictive. Thus, a combination of these 3 markers provides the best estimate of the risk of disease progression for each patient. CONCLUSIONS Our results suggest that HIV DNA level could be a useful additional marker in clinical practice and could aid in helping to define the best time to initiate treatment for each patient.

HIV-1 RNA detection in plasma for the diagnosis of infection in neonates

The objective of this study was to assess the frequency of detection of HIV-1 RNA in plasma of neonates born to HIV-1-seropositive mothers and to determine the diagnostic value of this method in the neonatal period. The study involved 96 infants among those enrolled in the French National Prospective Study. HIV-1 RNA was detected in the first 10 days of life by nucleic acid sequence-based amplification (NASBA) in 12 of 48 plasma samples of infected infants and in 39 of 39 of the second samples taken before the age of 3 months. On the same samples, peripheral blood mononuclear cell (PBMC) DNA polymerase chain reaction (PCR) or viral culture that had been routinely performed were found to be positive in 11 of 48 samples taken in the first 10 days of life and 39 of 39 second samples. For the noninfected infants, HIV-1 RNA was never detected in the 48 samples taken in the first 10 days of life and was detected in one of the 48 samples taken before the age of 3 months. HIV-1 RNA detection in plasma by NASBA has sensitivity and specificity equal to those of DNA PCR and culture on PBMC for the diagnosis of infection in infants with the clade B virus. This standardized method gives rapid results on a small volume of plasma and seems well suited for diagnosis on a large scale.

Early control of HIV replication in primary HIV-1 infection treated with antiretroviral drugs and pegylated IFNα : results from the Primoferon A (ANRS 086) study

IFN alpha has both antiviral and immunostimulating properties. The ANRS086 Primoferon A Study evaluated in 12 patients with primary HIV infection the tolerance and efficacy of an early and transient administration of pegylated IFN alpha, in addition to highly active antiretroviral therapy. Tolerance was good, and this regimen allowed the early control of HIV replication and rapid decay of the viral reservoir. These results support the initiation of comparative studies with pegylated INF alpha in primary HIV infection.

Frequent detection of HIV-1 in the gastric aspirates of neonates born to HIV-infected mothers.

OBJECTIVE To evaluate the frequency and correlates of oral route exposure of infants born to HIV-1-infected women. METHODS A multicenter study was performed within the prospective French Perinatal Cohort Study of mother-to-child HIV transmission. Oropharyngeal and gastric aspirates from 122 neonates were studied by reverse transcriptase (RT) polymerase chain reaction (PCR) for the presence of HIV-1, as well as for standard microbiology (Gram staining and culture). RESULTS Aspirates from 101 neonates were analyzed by RT-PCR; 28% of these were positive for HIV RNA. Another 21 aspirates could not be tested because of PCR inhibition. The median concentration of HIV RNA in the positive aspirates was 126 copies/ml (range: 8-1270). Detection of HIV-1 in the aspirate was significantly related to high maternal plasma-viral load, presence of blood in the aspirate, positive Gram stain or culture, episiotomy or perineal lesions, and sexually transmitted infections during the pregnancy. Most of the mothers received zidovudine prophylaxis during pregnancy and delivery. Among the six infants who were infected with HIV, three had positive aspirates. Of the three assumed to have acquired the infection intrapartum, only one had an HIV RNA-positive aspirate. CONCLUSION Exposure of the fetus to HIV via the oral route occurs frequently, even in the presence of zidovudine prophylaxis, and is likely to be one of the mechanisms of intrapartum transmission, but not the only one.

Performance of HIV-1 DNA or HIV-1 RNA Tests for Early Diagnosis of Perinatal HIV-1 Infection during Anti-Retroviral Prophylaxis

OBJECTIVE To compare performance of testing for human immunodeficiency virus (HIV)-1 DNA and HIV-1 RNA for diagnosis of HIV-1 infection in infants receiving preventive antiretroviral therapy. STUDY DESIGN This substudy of the French multicenter prospective cohort of neonates born to HIV-infected mothers, included 1567 infants tested for HIV with polymerase chain reaction (PCR) in a single laboratory, receiving post-natal prophylaxis, not breastfed, and having simultaneous HIV-1 DNA and RNA results before 45 days. The performance of PCR was assessed in reference to the 6-month HIV-1 RNA result. RESULTS Specificity of both HIV-1 RNA and HIV-1 DNA PCR was 100% at all ages (except 99.8% for DNA at birth); sensitivity was 58% (RNA) and 55% (DNA) at birth, and 89% at 1 month, 100% at 3 months for both, and 100% at 6 months (DNA). Concordance between HIV-1 DNA and RNA results was 0.78 and 0.81 (Kappa) at birth and 1 month and 100% at 3 and 6 months. Type of maternal and neonatal prophylaxis had no effect on sensitivity, but influenced viral load. CONCLUSION The performances of testing for HIV-1 DNA and RNA were similar with 100% sensitivity at 3 months. At 1 month during prophylaxis, 11% of infected children had negative PCR results.

Timing of mother-to-child HIV-1 transmission depends on maternal status

ObjectivesTo estimate when mother-to-child transmission occurs and investigate the possible role of maternal factors. DesignWe studied virological data obtained in the first 3 months of life of 95 infected newborns born to HIV-1-seropositive mothers included in the French Prospective Cohort Study who did not breast-feed. MethodsComparative Western blot analysis of sequential blood specimens from neonates and mothers with incomplete antibody patterns enabled us to detect antibody production in some infants. The results of viral investigation of neonate specimens enabled us to describe the acute phase of infection in newborns. Because the process between infection and antibody production is irreversible, we chose a Markov modelling technique, which is well suited for staged clinical processes. ResultsAbout two-thirds (65%) of the infants were considered to have been contaminated during delivery. In the remaining infants, the contamination was estimated to have occurred in utero and 95% of them had been infected less than 59 days before delivery. The association between the mothers immunological and virological status and the time of transmission was examined. The greater the degree of maternal immunodeficiency at delivery (in terms of p24 antigen and Western blot pattern) the higher the risk of in utero transmission, showing that vertical transmission is dependent on the mothers immunological status. ConclusionsThese estimates should be considered when designing strategies to prevent mother-to-child transmission.