Factors associated with HIV viral load control in the early postpartum period - a Canadian prospective cohort study

Despite success in managing HIV during pregnancy, challenges remain around sustained adherence with antiretroviral therapy (ART), and the suboptimal viral load (VL) suppression during the postpartum period. The objective of this study was to compare VL levels at delivery and during the postpartum period and assess factors associated with lack of viral suppression during the postpartum period in Canada. We combined data from two Canadian prospective cohorts, which included 286 HIV-positive women (352 pregnancies) who delivered between 2012 and 2020. Delivery VL, postpartum VL, and potential factors associated with an undetectable VL (<50 copies/mL), 2-18 weeks after delivery were assessed. To account for the correlation between multiple pregnancies from the same woman, generalized estimating equations were used to assess bivariate associations. Ninety-nine per cent of pregnant women were on ART during pregnancy compared to 93% during the postpartum period. Of those with available VL results (n = 214 pregnancies), 94% of women achieved an undetectable VL at delivery compared to 87% during the postpartum period. The postpartum period is a challenging time for ART use and VL control. Qualitative studies are needed to better understand these challenges and guide us in designing adequate interventions.

Relationship between raltegravir trough plasma concentration and virologic response and the impact of therapeutic drug monitoring during pregnancy

BACKGROUND

Limited data is available on raltegravir (RAL) pharmacokinetics during pregnancy and the value of therapeutic drug monitoring (TDM) in pregnancy is unknown. This study aims to describe RAL trough plasma concentrations (C_trough) during pregnancy and review the impact of RAL TDM on outcomes.

METHODS

Women from the prospective mother-infant HIV cohort of Mother and Children's Infectious Diseases Center who received RAL during their pregnancy between 2011-2020 were included. TDM reports were reviewed and C_trough values estimated when possible, using historical RAL half-lives.

RESULTS

We included 76 pregnant women of which 47 underwent TDM. We observed a significant association between virological response and C_trough (p-value .034) with an increase of 0.1 mg/L corresponding to a 2.96 reduction in the risk of having a detectable viral load. The results indicated that in pregnant women a RAL C_trough threshold of 0.04 mg/L has a higher specificity (75%) as compared to our current C_trough target value of 0.02 mg/L (25%) and an acceptable sensitivity (77%). No significant differences were observed between C_trough at each trimester. When comparing pregnancies with and without TDM, no statistically significant differences were observed in the virologic response during pregnancy and at delivery, or with the need for triple antiretroviral prophylaxis in newborns.

CONCLUSIONS

An association between RAL C_trough and viral load was observed and achieving a RAL C_trough of 0.04 mg/L or greater is a predictor of virologic response in pregnant women. The impact of TDM in pregnancy, however, could not be demonstrated.

Evaluation of cabergoline for lactation inhibition in women living with HIV

We wished to evaluate the efficacy, safety, and acceptability of cabergoline for lactation inhibition in women who live with HIV. In this multicenter prospective observational study, cabergoline was offered as a single oral dose of 1 mg within the first 48 h postpartum. Women were recruited if they delivered a live infant after 35 weeks of gestational age. Participants filled out a questionnaire regarding symptoms of lactation and cabergoline adverse effects on day 2 and day 14 postpartum. On day 14, they also completed a questionnaire about their satisfaction with cabergoline treatment. Prolactin serum level was measured on both visits. Among 68 participants, all but one received cabergoline. The overall effectiveness defined by partial or complete success at day 14 was 98.3% (confidence intervals: 89.5-99.9). At day 14, 67.4% of women who received cabergoline had prolactin serum levels <25 mcg/L (threshold necessary for galactopoiesis). Mild nonspecific adverse effects were experienced by 24 (29.9%) women on day 2 and 24 (41.4%) on day 14, and lasted 48 h or less. Overall, 96% of women were satisfied with cabergoline's ability to prevent postpartum lactation symptoms. In conclusion, cabergoline is an effective, well-accepted, and well-tolerated medication for lactation inhibition in WLWH.

Perspectives of women on screening and prevention of CMV in pregnancy

OBJECTIVE

To assess the choice and attitude of pregnant women regarding CMV serological screening and CMV prevention behaviors in pregnancy.

STUDY DESIGN

In this cross-sectional study, pregnant women were recruited in a single center during routine prenatal screening tests at 11-16 weeks. Participants filled out a questionnaire assessing knowledge about congenital CMV (cCMV) infection, risk perception and willingness to have CMV serological screening as well as their attitude toward CMV prevention behaviors.

RESULTS

Among 234 pregnant women, 74.4 % (95 % confidence interval: 68.8-80.0 %) wanted CMV serological screening in pregnancy. The factors significantly associated with the desire for screening were perceived risk and perceived severity of cCMV. An informed choice regarding CMV screening (value-consistent, based on good knowledge and deliberated) was performed by 54 % of women who chose the screening and 30 % of women who declined the screening (p = 0.039). The median scores regarding attitudes toward CMV prevention behaviors were 3.7/5 for avoiding sharing behaviors and 4.0/5 for not kissing a child on the lips.

CONCLUSION

The majority of pregnant women want to have CMV serological screening once informed about congenital CMV infection. New tools need to be developed to allow for informed choice regarding CMV serological screening in pregnancy.

Prenatal findings, neonatal symptoms and neurodevelopmental outcome of congenital cytomegalovirus infection in a university hospital in Montreal, Quebec

Background Outcome of congenital cytomegalovirus (cCMV) infection in the absence of routine CMV screening and third-trimester scan in North America is scarcely documented. The aim of this study was to assess the severe outcomes related to cCMV according to the indication for screening. Methods This was a retrospective study of 84 mother-child pairs followed for cCMV between 2003 and 2017 at CHU Sainte-Justine in Montreal, Canada. Prenatal ultrasound, neonatal symptoms, neuroimaging and severe outcomes (cerebral palsy, severe cognitive impairment, bilateral hearing loss or neonatal death) were reviewed. Results Among 38 cases with abnormal prenatal ultrasound, 41.9% of live-born infants developed severe outcomes. Sixteen (42.1%) were detected in the third trimester. Among 16 cases diagnosed prenatally because of maternal history, all had normal prenatal ultrasound, and none developed severe outcomes. Among cases diagnosed postnatally because of neonatal symptoms, 25% developed severe outcomes. All infants who developed severe outcomes had moderate/severe neonatal symptoms. Conclusion Outcome of cCMV infection varies according to the reason for screening and timing of diagnosis. Any prenatal ultrasound anomaly might indicate a risk of severe outcome, and warrants a detailed ultrasound scan. However, late detection, or postnatal diagnosis, represented more than half of the cases, and awareness of this will help ensuring optimal management.

Pregnancies Among the First Generation of Survivors of Perinatal HIV Infection

OBJECTIVE

Little is known about pregnancy outcomes among women who have acquired human immunodeficiency virus (HIV) through perinatal infection and survived into adulthood. The objectives of this study were to describe pregnancy outcomes among women with perinatal HIV infection (PHIV) in Canada and to identify potential challenges in the prevention of perinatal HIV transmission in this population.

METHODS

A retrospective review of all pregnancies among women with PHIV who were previously followed as children at two tertiary care centres in Montréal, Québec, was conducted. Data were extracted from pediatric and obstetrical records.

RESULTS

There were 21 pregnancies among 11 women, and 18 of these pregnancies were unintentional. Mean age at first pregnancy was 19.5 years (range 15-29 years). At the first prenatal visit, 79% had a detectable viral load, 36% were immunosuppressed (CD4 T cell count <200 mm³), and only 36% were receiving antiretroviral therapy (ART). At the time of delivery, although all were prescribed ART, 50% of these women still had a detectable viral load, and 36% remained immunosuppressed. All of the women harboured mutations conferring drug resistance to zidovudine and lamivudine, and the majority (73%) were also resistant to nevirapine. None of the infants were HIV infected, although all received prophylaxis with agents to which their mother's virus was resistant.

CONCLUSION

Unplanned pregnancies, difficulties with adherence to ART, and drug resistance were identified challenges in the management of pregnancies among women with PHIV. This study highlights a gap in the reproductive counselling of adolescents with PHIV and the need for close follow-up and adherence support during pregnancy in this population.

No association between early antiretroviral therapy during pregnancy and plasma levels of angiogenic factors: a cohort study

Background

Early antiretroviral therapy (ART) during pregnancy has dramatically reduced the risk of perinatal HIV transmission. However, studies have shown an association between premature delivery and the use of ART during pregnancy (particularly protease inhibitor (PI)-based therapies), which could be explained by placental dysfunction. The objective of this study was to evaluate the association of ART (class, duration of exposure and time of initiation) with placental function by using angiogenic factors placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) as biomarkers.

Methods

Clinical and biological data from 159 pregnant women living with HIV were analyzed. Levels of each biomarker were measured in the first and second trimester of pregnancy. After logarithmic transformation, we compared these using generalized estimating equations according to (a) the type of ART; (b) the duration of exposure to ART; and (c) the time of initiation of ART.

Results

After adjusting for variables such as ethnicity, maternal age, gestational age, body mass index, parity, smoking status, and sex of the fetus, we found no significant association between the class of ART (PI-based or not) and serum concentrations of PlGF or sFlt-1. Furthermore, no significant association was found between biomarker levels and the duration of ART exposure or the timing of ART initiation (pre- or post-conception).

Conclusions

This study suggests that first and second trimester angiogenic factor levels are not significantly associated with ART, regardless of the duration or type (with or without PI). These observations seem reassuring when considering the use of ART during early pregnancy.

Quasispecies Diversity Is a Major Risk Factor for Vertical Hepatitis C Virus Transmission

BACKGROUND

Vertical transmission is the major cause of pediatric hepatitis C virus (HCV) infection. The objective of this study was to better understand HCV pathogenesis in pregnant women and provide insights into risk factors and mechanisms involved in vertical transmission.

METHODS

Evolutionary dynamics of HCV variant spectra and HCV-specific neutralizing antibody responses were examined using high-throughput sequencing and pseudoparticle-based assays in pregnant women monoinfected with HCV (n = 17) or coinfected with HCV and human immunodeficiency virus (HIV)-1 (n = 15).

RESULTS

Overall, statistically significant associations were found between HCV quasispecies diversity, selective pressure exerted on the HCV E2 envelope protein, and neutralizing activity of maternal immunoglobulins. Women with low quasispecies diversity displayed significantly higher mean aspartate aminotransferase and alanine aminotransferase levels throughout pregnancy, but this difference was restricted to monoinfected participants. Low quasispecies diversity and inefficient neutralizing activity were also significantly associated with vertical transmission, but only in the monoinfected group.

CONCLUSIONS

These results indicate that maternal neutralizing antibody responses play a role in the prevention of vertical HCV transmission, but not in presence of HIV-1 coinfection, and suggest that the mechanism of vertical transmission may be different between monoinfected and coinfected women. These findings could inform management strategies for the prevention of vertical HCV transmission.

A Randomized Controlled Trial of the Safety and Immunogenicity of Tetanus, Diphtheria, and Acellular Pertussis Vaccine Immunization During Pregnancy and Subsequent Infant Immune Response

Background

Immunization of pregnant women with tetanus-diphtheria-acellular pertussis vaccine (Tdap) provides protection against pertussis to the newborn infant.

Methods

In a randomized, controlled, observer-blind, multicenter clinical trial, we measured the safety and immunogenicity of Tdap during pregnancy and the effect on the infant's immune response to primary vaccination at 2, 4, and 6 months and booster vaccination at 12 months of age. A total of 273 women received either Tdap or tetanus-diphtheria (Td) vaccine in the third trimester and provided information for the safety analysis and samples for the immunogenicity analyses; 261 infants provided serum for the immunogenicity analyses.

Results

Rates of adverse events were similar in both groups. Infants of Tdap recipients had cord blood levels that were 21% higher than maternal levels for pertussis toxoid (PT), 13% higher for filamentous hemagglutinin (FHA), 4% higher for pertactin (PRN), and 7% higher for fimbriae (FIM). These infants had significantly higher PT antibody levels at birth and at 2 months and significantly higher FHA, PRN, and FIM antibodies at birth and 2 and 4 months, but significantly lower PT and FHA antibody levels at 6 and 7 months and significantly lower PRN and FIM antibody levels at 7 months than infants whose mothers received Td. Differences persisted prebooster at 12 months for all antigens and postbooster 1 month later for PT, FHA, and FIM.

Conclusions

This study demonstrated that Tdap during pregnancy results in higher levels of antibodies early in infancy but lower levels after the primary vaccine series.

Clinical Trials Registration

NCT00553228.

No. 96-The Reproductive Care of Women Living With Hepatitis C Infection

OBJECTIVE

hepatitis C virus (HCV) is an increasingly important public health problem worldwide. Health care workers providing care to women of childbearing age are uniquely placed in their practices to identify a significant proportion of at-risk patients and to provide appropriate screening and counselling. The primary objective of this guideline is to provide accurate, current information to those offering reproductive care to women living with HCV. This document is also intended to raise awareness of HCV in both the medical and general populations.

OPTIONS

the areas of clinical practice considered in formulating this guideline are disease prevention, targeted screening of individuals at risk of contracting HCV, management of identified patients in the context of reproductive care, and the appropriate referral of patients to those with particular expertise.

OUTCOMES

implementation of these guidelines should facilitate identification of infected individuals. It should also result in improved physical and mental well-being for patients and their families and reduction in transmission rates.

EVIDENCE

the literature between 1966 and 2000, including non- English language publications, was extensively searched utilizing Medline. A multidisciplinary group consisting of experts within the fields of obstetrics and gynaecology, infectious diseases, hepatology, and public health convened in Montreal in February 2000. The working group also included a patient and a representative from the Hepatitis C Society of Canada. The level of evidence for the recommendations has been determined using the criteria described by the Canadian Task Force on Periodic Health Examination.

BENEFITS, HARMS AND COSTS

the public health benefits of increased identification of at-risk individuals, diagnosis, treatment, implementation of risk reduction behaviours, and reduced transmission rates, both on an individual and at the community level, are significant. However, it must be remembered that the diagnosis of a chronic disease may have far reaching effects for the individual patient and her family.

RECOMMENDATIONS

VALIDATION: references were collected through Medline searches and comparison made to existing current guidelines for assessment of consistency. External reviewers expert in their field were also consulted.

The association between antiretroviral therapy and early placental function: a cohort study

Objective: To evaluate the association of antiretroviral therapy (ART) type and duration of exposure with early placental function using biomarkers of aneuploidy screening.Study design: Three hundred thirty-eight pregnant women living with HIV were enrolled in two Canadian centers. Multiple linear regressions were performed adjusting for confounding factors (race, age, gestational age, body mass index, parity, smoking, and fetal sex).Results: Women receiving ART had significantly increased second trimester alpha-fetoprotein (AFP) levels (β = 0.147, 95% CI = [0.067-0.227] for protease inhibitor-based ART and β = 0.176, 95% CI = [0.080-0.272] for ART without protease inhibitor) compared to women who received no treatment. However, there was no significant association between ART type and the levels of free β-human chorionic gonadotrophin (β-hCG), pregnancy-associated plasma protein-A (first trimester), unconjugated estriol, total hCG, and inhibin A (second trimester). No significant association was shown between biomarker levels and duration of ART exposure.Conclusion: Early placental function does not appear to be significantly affected by ART, except for AFP.

Use of Cytomegalovirus-Specific Hyperimmunoglobulins in Pregnancy: A Retrospective Cohort

OBJECTIVE

There is no consensus on the use of cytomegalovirus (CMV)-specific hyperimmunoglobulins (CSHIGs) for suspected congenital CMV infections during pregnancy, but this therapy is currently used in some countries. The objectives of this study were to describe tolerability and pregnancy outcome following treatment with monthly intravenous CSHIG and compare rates of positive PCR and postnatal symptoms according to whether CSHIGs were given or not.

METHODS

This retrospective cohort study included all pregnant women who were diagnosed with primary CMV infection or congenital CMV infection at the Centre Hospitalier Universitaire Sainte-Justine (Montreal, QC) between 2005 and 2016. CSHIG was discussed with pregnant women who received positive CMV PCR results from amniotic fluid or if ultrasound anomalies suggested congenital infection and there was serologic evidence of maternal primary infection (therapeutic group). CSHIG was also offered as prophylaxis in pregnant women without fetal ultrasound anomalies but with evidence of maternal primary infection, when amniocentesis either had negative results or was not performed (prophylactic group). A matched analysis was performed to control for timing of maternal infection, amniocentesis, and type and timing of ultrasound anomaly.

RESULTS

Sixteen women received CSHIG, and 55 had no CMV-specific treatment. CSHIG treatment was well-tolerated. In bivariate analyses, the risk of congenital CMV infection and postnatal symptoms did not significantly decrease with CSHIG treatment, in both the therapeutic and the prophylactic groups. After matching, there was still no difference in outcomes between CSHIG-treated and untreated women.

CONCLUSION

The effectiveness of CSHIG in preventing congenital CMV infection and its clinical manifestations could not be demonstrated.

Optimization of pegylated iron oxide nanoplatforms for antibody coupling and bio-targeting

PEGylation has been established as a valuable strategy to minimize nanoparticle clearance by the reticulo-endothelial system due to hydrophilicity and steric repulsion of PEG chains. In this study we functionalized superparamagnetic iron oxide nanoparticle surface with two PEG differing in their length (n = 23 and 44) and terminal functionality, COOH and CH₃. By varying the ratio of the two different PEG, we optimized the molecular architecture of the nanoplatform to obtain maximum stability and low toxicity under physiological conditions. The best nanoplatform was evaluated as MRI contrast for mouse brain vascularization imaging at 7 T. The carboxylic acid functions of the nanoplatform were used to covalently bind an antibody, Ab. This antibody, labeled with a fluorophore, targets the ET_A receptor, a G-protein-coupled receptor involved in the endothelin axis and overexpressed in various solid tumours, including ovarian, prostate, colon, breast, bladder and lung cancers. In vitro studies, performed by flow cytometry and magnetic quantification, showed the targeting efficiency of the Ab-nanoplatforms. Clearly, an imaging tracer for cancer diagnosis from a bimodal contrast agent (fluorescence and MRI) was thus obtained.

Genetically tailored magnetosomes used as MRI probe for molecular imaging of brain tumor

We investigate here the potential of single step production of genetically engineered magnetosomes, bacterial biogenic iron-oxide nanoparticles embedded in a lipid vesicle, as a new tailorable magnetic resonance molecular imaging probe. We demonstrate in vitro the specific binding and the significant internalization into U87 cells of magnetosomes decorated with RGD peptide. After injection at the tail vein of glioblastoma-bearing mice, we evidence in the first 2 h the rapid accumulation of both unlabeled and functionalized magnetosomes inside the tumor by Enhanced Permeability and Retention effects. 24 h after the injection, a specific enhancement of the tumor contrast is observed on MR images only for RGD-labeled magnetosomes. Post mortem acquisition of histological data confirms MRI results with more magnetosomes found into the tumor treated with functionalized magnetosomes. This work establishes the first proof-of-concept of a successful bio-integrated production of molecular imaging probe for MRI.

Enhancement of Carbon Nanofibers Dispersion on Epoxy Resin Foams Leading to Remarkable Electrical Conductivity Improvement

A simple procedure to evaluate and improve the dispersion of carbon nanofibers is presented and validated, relating the observed dispersion of the nanofibers in an intermediate stage of the production process to the final macroscopic properties of the foams. Epoxy/carbon nanofiber foams with optimal nanofiber dispersion are produced taking advantage of this procedure using inexpensive industrial vapor grown carbon nanofibers. Furthermore, the main characteristics and the electrical resistivity of the foams with improved nanofibers dispersion have been determined and related to the presence of the carbon nanofibers, greatly enhancing the electrical conductivity of the epoxy/carbon nanofiber foams.

Possible Atazanavir-Induced Cholelithiasis in a Pregnant Woman: A Case Report

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Model-Based Network Meta-Analysis: A Framework for Evidence Synthesis of Clinical Trial Data

Model-based meta-analysis (MBMA) is increasingly used in drug development to inform decision-making and future trial designs, through the use of complex dose and/or time course models. Network meta-analysis (NMA) is increasingly being used by reimbursement agencies to estimate a set of coherent relative treatment effects for multiple treatments that respect the randomization within the trials. However, NMAs typically either consider different doses completely independently or lump them together, with few examples of models for dose. We propose a framework, model-based network meta-analysis (MBNMA), that combines both approaches, that respects randomization, and allows estimation and prediction for multiple agents and a range of doses, using plausible physiological dose-response models. We illustrate our approach with an example comparing the efficacies of triptans for migraine relief. This uses a binary endpoint, although we note that the model can be easily modified for other outcome types.

Awareness of cytomegalovirus and risk factors for susceptibility among pregnant women, in Montreal, Canada

BACKGROUND

Advances in diagnostic and therapeutic modalities for congenital cytomegalovirus (CMV) infection have generated a mounting interest in identifying mothers susceptible to CMV. The objectives of this study were to evaluate the prevalence and socio-demographic determinants of CMV susceptibility and CMV awareness, among pregnant women, in Montreal, Quebec.

METHODS

Between April and December 2012, women delivering at Centre Hospitalier Universitaire Sainte Justine were recruited for the study. Stored serum from the first trimester of pregnancy was tested for CMV IgG. Knowledge about CMV and socio-demographic characteristics were collected via standardized questionnaire.

RESULTS

Four hundred and ninety one women were enrolled in the study. Overall, 225 mothers (46%) were seronegative for CMV, and 85% (n = 415) were unaware of CMV or the associated risks in pregnancy. Significant risk factors for CMV seronegative status included Canadian vs. foreign born (aOR 6.88, 95% CI 4.33-10.94), and high vs. low family income (aOR 4.68, 95% CI 2.09-10.48). Maternal employment status was the only significant predictor of CMV unawareness, with unemployed mothers at the highest risk (aOR 85.6, 95% CI 17.3-421.3).

CONCLUSIONS

Nearly half of pregnant women studied were at risk of primary infection, and yet, the majority was unaware of potential risks associated with CMV. Canadian born mothers and those with a high socioeconomic status were more likely to be CMV seronegative. Increased education about CMV infection, through public health interventions and obstetrician/pediatric counseling, is needed for all pregnant women.

The Many Flavors of Model-Based Meta-Analysis: Part I-Introduction and Landmark Data

Meta-analysis is an increasingly important aspect of drug development as companies look to benchmark their own compounds with the competition. There is scope to carry out a wide range of analyses addressing key research questions from preclinical through to postregistration. This set of tutorials will take the reader through key model-based meta-analysis (MBMA) methods with this first installment providing a general introduction before concentrating on classical and Bayesian methods for landmark data.

Risk factors for pre-term birth in a Canadian cohort of HIV-positive women: role of ritonavir boosting?

BACKGROUND

The risk of pre-term birth (PTB) associated with the use of protease inhibitors (PIs) during pregnancy remains a subject of debate. Recent data suggest that ritonavir boosting of PIs may play a specific role in the initiation of PTB, through an effect on the maternal-fetal adrenal axis. The primary objective of this study is to compare the risk of PTB among women treated with boosted PI versus non-boosted PIs during pregnancy.

METHODS

Between 1988 and 2011, 705 HIV-positive women were enrolled into the Centre Maternel et Infantile sur le SIDA mother-infant cohort at Centre Hospitalier Universitaire Sainte-Justine in Montreal, Canada. Inclusion criteria for the study were: 1) attendance at a minimum of two antenatal obstetric visits and 2) singleton live birth, at 24 weeks gestational or older. The association between PTB (defined as delivery at <37 weeks gestational age), antiretroviral drug exposure and maternal risk factors was assessed retrospectively using logistic regression.

RESULTS

A total of 525 mother-infant pairs were included in the analysis. Among them, PI-based combination anti-retroviral therapy was used in 37.4%, boosted PI based in 24.4%, non-nucleoside reverse transcriptase inhibitor (NNRTI) or nucleoside reverse transcriptase inhibitor based in 28.1%, and no treatment was given in 10.0% of cases. Overall, 13.5% of women experienced PTB. Among women treated with antiretroviral therapy, the risk of PTB was significantly higher among women who received boosted versus non-boosted PI (OR 2.01, 95% CI 1.02-3.97). This remained significant after adjusting for maternal age, delivery CD4 count, hepatitis C co-infection, history of previous PTB, and parity (aOR 2.17, 95% CI 1.05-4.51). There was no increased risk of PTB with the use of unboosted PIs as compared to NNRTI- or NRTI-based regimens.

CONCLUSION

While previous studies on the association between PTB and PI use have generally considered all PIs the same, our results would indicate a possible role of ritonavir boosting as a risk factor for PTB. Further work is needed to understand the pathophysiologic mechanisms involved, and to identify the safest ARV regimens to be used in pregnancy.

Endothelin B receptors targeted by iron oxide nanoparticles functionalized with a specific antibody: toward immunoimaging of brain tumors

Vasculature enhancement is observed in mouse brain after intravenous injection of iron oxide nanoparticles functionalized with antibody targeting endothelin B receptors over-expressed in glioma.

[Intraoperative avoidance and recognition of recurrent laryngeal nerve palsy in thyroid surgery]

Recurrent laryngeal nerve palsy is an intrinsic complication of thyroid surgery. Prevention of nerve palsy is considered to be a feature of quality in this very frequently performed operation. Risk factors and prevention strategies are demonstrated and discussed with reference to the current literature. Exact knowledge of the anatomy and possible variants of the track of the recurrent laryngeal nerve as well as its visualization and careful dissection are the cornerstones for nerve preservation. The use of intraoperative neuromonitoring allows preservation of the anatomical structure and functional integrity of the nerve and lesions which are not visible can be detected. Preconditions for correct interpretation are a standardized application and preoperative and postoperative laryngoscopy.

Increase in transaminase levels following the use of raltegravir in a woman with a high HIV viral load at 35 weeks of pregnancy

BACKGROUND

Despite the efficacy of raltegravir in reducing viral load in HIV-infected patients, evidence for its safety in late pregnancy is lacking. A high rate of placental transfer was recently demonstrated.

CASE

A treatment-naïve 34-year-old HIV-1-positive woman of African origin began treatment with zidovudine/lamivudine, lopinavir/ritonavir, and raltegravir at 35 weeks of pregnancy. After 11 days of treatment with raltegravir, a substantial reduction in viral load was achieved. Concurrently, she had a 23-fold increase in serum alanine aminotransferase and a 10-fold increase in serum aspartate aminotransferase, both of which returned to normal when raltegravir treatment was discontinued. A healthy boy was delivered at term. The infant's tests for HIV were negative at five months, and he had no health problems at eight months.

CONCLUSION

This is the first case report, to our knowledge, of increased maternal serum transaminase levels following the use of raltegravir in a woman at a late stage of pregnancy.

Impact of maternal HIV-1 viremia on lymphocyte subsets among HIV-exposed uninfected infants: protective mechanism or immunodeficiency

BACKGROUND

Reports of increased morbidity and mortality from infectious diseases among HIV Exposed Uninfected (HEU) infants have raised concern about a possible underlying immunodeficiency among them. The objective of this study was to assess the immunological profile of HEU infants born to mothers exhibiting different levels of HIV-1 viremia at the time of delivery.

METHODS

Study subjects were enrolled in the Centre maternel et infantile sur le SIDA (CMIS) mother-child cohort between 1997 and 2010 (n =585). Infant CD4+ T cell, CD8+ T cell and CD19+ B cell counts were assessed at 2 and 6 months of age, and compared among HEU infants in groups defined by maternal viral load (VL) at the time of delivery (VL < 50 copies/ml, VL 50-1000 copies/ml, and VL > 1000 copies/ml) in a multivariable analysis.

RESULTS

At 2 months of age, infants born to mothers with VL > 1000 copies/ml had lower CD4+ T cell counts compared to those born to mothers with VL < 50 copies/ml at the time of delivery (44.3% versus 48.3%, p = 0.007, and 2884 vs. 2432 cells/mm3, p = 0.02). These differences remained significant after adjusting for maternal and infant antiretroviral drug use, gender, race and gestational age, and persisted at 6 months of age. There were no differences in CD8+ T cell count or absolute CD19+ B cell count between groups, though higher CD19+ B cell percentage was seen among infants born to mothers with VL > 1000 copies/ml.

CONCLUSIONS

These results suggest that exposure to high levels of HIV-1 viremia in utero, even in the absence of perinatal transmission, may affect the infant's developing immune system. While further work needs to be done to confirm these findings, they reinforce the need for optimal treatment of HIV infected pregnant women, and careful follow-up of HEU infants.

Evolution of HIV-1 coreceptor usage and coreceptor switching during pregnancy

Coreceptor switch from CCR5 to CXCR4 is associated with HIV disease progression. To document the evolution of coreceptor tropism during pregnancy, a longitudinal study of envelope gene sequences was performed in a group of pregnant women infected with HIV-1 of clade B (n=10) or non-B (n=9). Polymerase chain reaction (PCR) amplification of the V1-V3 region was performed on plasma viral RNA, followed by cloning and sequencing. Using geno2pheno and PSSMX4R5, the presence of X4 variants was predicted in nine of 19 subjects (X4 subjects) independent of HIV-1 clade. Six of nine X4 subjects exhibited CD4(+) T cell counts <200 cells/mm(3), and the presence of X4-capable virus was confirmed using a recombinant phenotypic assay in four of seven cases where testing was successful. In five of nine X4 subjects, a statistically significant decline in the geno2pheno false-positive rate was observed during the course of pregnancy, invariably accompanied by progressive increases in the PSSMX4R5 score, the net charge of V3, and the relative representation of X4 sequences. Evolution toward X4 tropism was also echoed in the primary structure of V2, as an accumulation of substitutions associated with CXCR4 tropism was seen in X4 subjects. Results from these experiments provide the first evidence of the ongoing evolution of coreceptor utilization from CCR5 to CXCR4 during pregnancy in a significant fraction of HIV-infected women. These results inform changes in host-pathogen interactions that lead to a directional shaping of viral populations and viral tropism during pregnancy, and provide insights into the biology of HIV transmission from mother to child.

Bioengineering the hair follicle

The hair follicle develops from the primitive embryonic epidermis as a result of complex epithelial-mesenchymal interactions. The full follicle, consisting of epithelial cylinders under control of a proximal lying mesenchymal papilla, grows in cycles giving rise to a new hair shaft during each cycle. The ability to cycle endows the follicle with regenerative properties. The evolution of hair follicle engineering began with the recognition in the early 1960's that hair follicles could be transplanted clinically into a foreign site and still grow a shaft typical of the donor site. Since that time, it has been found that the follicular papilla has hair follicle inducing properties and that the hair follicle houses within it epithelial stem cells that can respond to hair inductive signals. These findings have laid the foundation for isolating hair-forming cells, for expanding the cells in culture, and for forming new follicles in vivo.

Novel HIV-1 recombinant forms in antenatal cohort, Montreal, Quebec, Canada

Near full-length genomes of 4 unclassified HIV-1 variants infecting patients enrolled in an antenatal cohort in Canada were obtained by sequencing. All 4 variants showed original recombination profiles, including A1/A2/J, A1/D, and A1/G/J/CRF11_cpx structures. Identification of these variants highlights the growing prevalence of unique recombinant forms of HIV-1 in North America.

Antibioprophylaxie dans le cadre d'interventions obstétricales

Objectif

Analyser les résultats et formuler des recommandations sur le recours à l'antibioprophylaxie dans le cadre d'interventions obstétricales.

Issues

Parmi les issues évaluées, on trouve la nécessité et l'efficacité du recours à des antibiotiques aux fins de la prévention des infections dans le cadre d'interventions obstétricales.

Résultats

La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans Medline et The Cochrane Library au moyen de la rubrique « antibioprophylaxie dans le cadre d'interventions obstétricales ». Les résultats ont été restreints aux analyses systématiques, aux essais comparatifs randomisés / essais cliniques comparatifs et aux études observationnelles. Les recherches ont été mises à jour de façon régulière et les articles publiés entre janvier 1978 et juin 2009 ont été incorporés à la directive clinique. Les lignes directrices actuellement publiées par le American College of Obstetrics and Gynecology ont également été incorporées à la directive clinique. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales.

Valeurs

Les résultats obtenus ont été analysés et évalués par le comité sur les maladies infectieuses de la Société des obstétriciens et gynécologues du Canada sous la gouverne des auteures principales, et les recommandations ont été formulées conformément aux lignes directrices élaborées par le Groupe d'étude canadien sur les soins de santé préventifs (Tableau 1).

Avantages, désavantages et coûts

La mise en œuvre de la présente directive clinique devrait réduire les coûts et les torts attribuables à l’administration d’antibiotiques lorsque celle-ci ne s’avère pas requise, ainsi que les torts attribuables à la non-administration d’antibiotiques lorsque ceux-ci pourraient s’avérer bénéfiques.

Déclarations sommaires

1.

Les données disponibles ne soutiennent pas le recours à l'antibioprophylaxie en vue d'atténuer la morbidité infectieuse à la suite d'un accouchement vaginal opératoire. (II-1)

2.

Nous ne disposons pas de données suffisantes pour soutenir ou déconseiller le recours à l'antibioprophylaxie en vue d'atténuer la morbidité infectieuse dans les cas de retrait manuel du placenta. (III)

3.

Nous ne disposons pas de données suffisantes pour soutenir ou déconseiller le recours à l'antibioprophylaxie au moment de la dilatation-curetage postpartum visant des produits de conception en rétention. (III)

4.

Les données disponibles ne soutiennent pas le recours à l'antibioprophylaxie en vue d'atténuer la morbidité infectieuse à la suite d'un cerclage planifié ou d'urgence. (II-3)

Recommandations

1.

Toutes les femmes qui subissent une césarienne planifiée ou d'urgence devraient se voir administrer une antibioprophylaxie. (I-A)

2.

Une dose unique d'une céphalosporine de première génération devrait constituer l'antibiotique à privilégier pour ce qui est des césariennes. Lorsque la patiente présente une allergie à la pénicilline, on peut avoir recours à la clindamycine ou à l'érythromycine. (I-A)

3.

Dans le cas de la césarienne, l'antibioprophylaxie devrait être administrée de 15 à 60 minutes avant l'incision de la peau. Aucune dose additionnelle n'est recommandée. (I-A)

4.

Lorsqu'une intervention à abdomen ouvert est de longue durée (>3 heures) ou que la perte sanguine estimée est supérieure à 1 500 ml, une dose additionnelle d'antibiotique prophylactique peut être administrée de 3 à 4 heures à la suite de la dose initiale. (III-L)

5.

L'administration d'une antibioprophylaxie peut être envisagée pour atténuer la morbidité infectieuse associée à la réparation d'une lésion périnéale du troisième ou du quatrième degré. (I-B)

6.

Chez les patientes massivement obèses (IMC > 35), il est possible d'envisager le doublement de la dose d'antibiotiques. (III-B)

7.

L’administration d’antibiotiques aux seules fins de prévenir l’endocardite ne devrait pas être mise en œuvre chez les patientes qui doivent subir une intervention obstétricale, quelle qu’en soit la nature. (III-E)

Perinatal listeriosis: Canada's 2008 outbreaks

BACKGROUND

Listeriosis is one of the most severe foodborne illnesses worldwide. Most infections with Listeria are sporadic, but outbreaks do occur. Pregnant women exposed to this organism are at increased risk of chorioamnionitis, preterm labour, prematurity and intrauterine fetal demise. Severe neonatal infection can also occur.

CASES

Two recent outbreaks in Canada prompted a reassessment of the prevalence and the perinatal impact of this disease. We describe here three cases of perinatal listeriosis. The aim of our report is to demonstrate the variable clinical presentations and to emphasize the difficulty in diagnosing perinatal listeriosis.

CONCLUSION

Perinatal listeriosis is a severe disease with many possible clinical presentations. Clinical diagnosis may be difficult, so clinicians must maintain a high index of suspicion.

Behavioural signs of depression and apoptosis in the limbic system following myocardial infarction: effects of sertraline

Depression is diagnosed in 15-30% of patients following myocardial infarction (MI) and this may also be observed in the rat. We measured the effects of the antidepressant sertraline on behavioural and biochemical events following MI in a rat model. Following surgery, MI rats and sham controls were treated with sertraline (10 mg/kg, i.p.) or saline. Subgroups of rats were tested for behavioural depression 14 days after surgery. Apoptosis was estimated in other rats by measuring caspase-3 activity and TUNEL positive cells (3 days after surgery) in limbic structures (amygdale, hippocampus, hypothalamus, frontal and prefrontal cortices). Bax/Bcl-2 ratio was measured 14 days after surgery. Behavioural signs of depression (decreased sucrose intake and forced swimming time) were found in saline-treated MI rats but not in sertraline-treated rats. Compared with controls, caspase-3 activity and TUNEL positive cells were significantly increased in most limbic structures of MI rats. High prefrontal Bax/Bcl-2 ratio in MI rats correlated with low forced swimming time. Apoptosis was not found in sertraline-treated MI rats. These results establish the bases of a rat model of depression following MI and show for the first time that a selective serotonin reuptake inhibitor prevents both behavioural and biochemical markers in this model.