Intestinal barrier disruption with Plasmodium falciparum infection in pregnancy and risk of preterm birth: a cohort study.

BACKGROUND: Malaria in early pregnancy is a risk factor for preterm birth and is associated with sustained inflammation and dysregulated angiogenesis across gestation. This study investigated whether malaria is associated with increased gut leak and whether this contributes to systemic inflammation, altered angiogenesis, and preterm birth. METHODS: We quantified plasma concentrations of gut leak markers, soluble CD14 (sCD14) and lipopolysaccharide binding protein (LBP) from 1339 HIV-negative pregnant Malawians at <24 weeks gestational age. We assessed the relationship of sCD14 and LBP concentrations with markers of inflammation, angiogenesis, and L-arginine bioavailability and compared them between participants with and without malaria, and with and without preterm birth. FINDINGS: Plasma concentrations of sCD14 and LBP were significantly higher in participants with malaria and were associated with parasite burden (p <0.0001, both analyses and analytes). The odds ratio for preterm birth associated with one log sCD14 was 2.67 (1.33 to 5.35, p = 0.006) and 1.63 (1.07-2.47, p = 0.023) for LBP. Both gut leak analytes were positively associated with increases in proinflammatory cytokines CRP, sTNFR2, IL18-BP, CHI3L1 and Angptl3 (p <0.05, all analytes) and sCD14 was significantly associated with angiogenic proteins Angpt-2, sENG and the sFLT:PlGF ratio (p <0.05, all analytes). sCD14 was negatively associated with L-arginine bioavailability (p <0.001). INTERPRETATION: Malaria in early pregnancy is associated with intestinal barrier dysfunction, which is linked to an increased risk of preterm birth. FUNDING: Open Philanthropy, Canadian Institutes of Health Research, Canada Research Chair program, European and Developing Countries Clinical Trials Partnership, Bill & Melinda Gates Foundation.

Inflammatory profiles in febrile children with moderate and severe malnutrition presenting at-hospital in Uganda are associated with increased mortality.

BACKGROUND: Children in Africa carry a disproportionate burden of malnutrition and infectious disease. Together, malnutrition and infection are major contributors to global child mortality; however, their collective impact on immune activation are not well described. METHODS: This was a secondary analysis of a prospective cohort study of children hospitalized with acute febrile illness at a single centre in Uganda. We investigated the association between malnutrition (determined using the mid-upper arm circumference, MUAC), immune activation (as measured by inflammatory markers IL-6, IL-8, CXCL10, CHI3L1, sTNFR1, Cystatin C, granzyme B, and sTREM-1), and mortality. FINDINGS: Of the 1850 children eligible for this secondary analysis, 71 (3.8%) and 145 (11.7%) presented with severe acute malnutrition (SAM, MUAC <115 mm) and moderate malnutrition (MUAC 115 to < 125 mm), respectively. SAM was associated with increased concentrations of CHI3L1, sTNFR1, Cystatin C, and sTREM-1, and decreased concentrations of CXCL10 and granzyme B, even after controlling for age, sex, and disease severity at presentation. There were 77 deaths (4.2%). SAM was associated with a 9.2-fold (95% CI 4.8-46), 17-fold (95% CI 3.9-74), and 13-fold (95% CI 3.5-52) increased odds of death in children with pneumonia, malaria, and diarrheal illness, respectively. Mediation analysis implicated sTREM-1 and CHI3L1 in the effect of SAM on mortality, suggesting that enhanced activation of these inflammatory pathways is associated with the increased mortality in undernourished children with pneumonia and malaria. INTERPRETATION: Collectively, these data highlight systemic inflammation as a common pathway associated with malnutrition and infection that could be targeted to mitigate the burden of acute febrile illness in LMICs. FUNDING: This work was supported in part by the Canadian Institutes of Health Research, and by kind donations from The Tesari Foundation and Kim Kertland. The funders had no role in design, analysis, or reporting of these studies.

Sequential disruptions to inflammatory and angiogenic pathways and risk of spontaneous preterm birth in Malawian women.

Preterm birth is a leading cause of death in children under five years of age. We hypothesized that sequential disruptions to inflammatory and angiogenic pathways during pregnancy increase the risk of placental insufficiency and spontaneous preterm labor and delivery. We conducted a secondary analysis of inflammatory and angiogenic analytes measured in plasma samples collected across pregnancy from 1462 Malawian women. Women with concentrations of the inflammatory markers sTNFR2, CHI3L1, and IL18BP in the highest quartile before 24 weeks gestation and women with anti-angiogenic factors sEndoglin and sFlt-1/PlGF ratio in the highest quartile at 28-33 weeks gestation had an increased relative risk of preterm birth. Mediation analysis further supported a potential causal link between early inflammation, subsequent angiogenic dysregulation detrimental to placental vascular development, and earlier gestational age at delivery. Interventions designed to reduce the burden of preterm birth may need to be implemented before 24 weeks of gestation.

Prognostic accuracy of biomarkers of immune and endothelial activation in Mozambican children hospitalized with pneumonia.

Pneumonia is a leading cause of child mortality. However, currently we lack simple, objective, and accurate risk-stratification tools for pediatric pneumonia. Here we test the hypothesis that measuring biomarkers of immune and endothelial activation in children with pneumonia may facilitate the identification of those at risk of death. We recruited children <10 years old fulfilling WHO criteria for pneumonia and admitted to the Manhiça District Hospital (Mozambique) from 2010 to 2014. We measured plasma levels of IL-6, IL-8, Angpt-2, sTREM-1, sFlt-1, sTNFR1, PCT, and CRP at admission, and assessed their prognostic accuracy for in-hospital, 28-day, and 90-day mortality. Healthy community controls, within same age strata and location, were also assessed. All biomarkers were significantly elevated in 472 pneumonia cases versus 80 controls (p<0.001). IL-8, sFlt-1, and sTREM-1 were associated with in-hospital mortality (p<0.001) and showed the best discrimination with AUROCs of 0.877 (95% CI: 0.782 to 0.972), 0.832 (95% CI: 0.729 to 0.935) and 0.822 (95% CI: 0.735 to 0.908), respectively. Their performance was superior to CRP, PCT, oxygen saturation, and clinical severity scores. IL-8, sFlt-1, and sTREM-1 remained good predictors of 28-day and 90-day mortality. These findings suggest that measuring IL-8, sFlt-1, or sTREM-1 at hospital presentation can guide risk-stratification of children with pneumonia, which could enable prioritized care to improve survival and resource allocation.

Soluble Urokinase-Type Plasminogen Activator Receptor as a Prognostic Marker of Ugandan Children at Risk of Severe and Fatal Malaria.

BACKGROUND: Current malaria diagnostic tests do not reliably identify children at risk of severe and fatal infection. Host immune and endothelial activation contribute to malaria pathogenesis. Soluble urokinase-type plasminogen activator receptor (suPAR) is a marker of these pathways. We hypothesized that measuring suPAR at presentation could risk-stratify children with malaria. METHODS: Plasma suPAR levels were determined in consecutive febrile children with malaria at presentation to hospital in Jinja, Uganda. We evaluated the accuracy of suPAR in predicting in-hospital mortality, and whether suPAR could improve a validated clinical scoring system (Lambaréné Organ Dysfunction Score [LODS]). RESULTS: Of the 1226 children with malaria, 39 (3.2%) died. suPAR concentrations at presentation were significantly higher in children who went on to die than in those who survived (P < .0001). suPAR levels were associated with disease severity (LODS: 0 vs 1, P = .001; 1 vs 2, P < .001; 2 vs 3, 0 vs 2, 1 vs 3, and 0 vs 3, P < .0001). suPAR concentrations were excellent predictors of in-hospital mortality (area under the receiver operating characteristic curve [AUROC], 0.92 [95% confidence interval {CI}, .91-.94]). The prognostic accuracy of LODS (AUROC, 0.93 [95% CI, .91-.94]) was improved when suPAR was added (AUROC, 0.97 [95% CI, .96-.98]; P < .0001). CONCLUSIONS: Measuring suPAR at presentation can identify children at risk of severe and fatal malaria. Adding suPAR to clinical scores could improve the recognition and triage of children at risk of death. suPAR can be detected with a point-of-care test and can now be evaluated in prospective trials.

Developmental origins of disease highlight the immediate need for expanded access to comprehensive prenatal care.

The prenatal environment plays a critical role in shaping fetal development and ultimately the long-term health of the child. Here, we present data linking prenatal health, via maternal nutrition, comorbidities in pregnancy (e.g., diabetes, hypertension), and infectious and inflammatory exposures, to lifelong health through the developmental origins of disease framework. It is well-established that poor maternal health puts a child at risk for adverse outcomes in the first 1,000 days of life, yet the full health impact of the in utero environment is not confined to this narrow window. The developmental origins of disease framework identifies cognitive, neuropsychiatric, metabolic and cardiovascular disorders, and chronic diseases in childhood and adulthood that have their genesis in prenatal life. This perspective highlights the enormous public health implications for millions of pregnancies where maternal care, and therefore maternal health and fetal health, is lacking. Despite near universal agreement that access to antenatal care is a priority to protect the health of women and children in the first 1,000 days of life, insufficient progress has been achieved. Instead, in some regions there has been a political shift toward deprioritizing maternal health, which will further negatively impact the health and safety of pregnant people and their children across the lifespan. In this article we argue that the lifelong health impact attributed to the perinatal environment justifies policies aimed at improving access to comprehensive antenatal care globally.

Allometric scaling relationships in mouse placenta.

Fetal growth and maturation are highly intertwined with placental development during pregnancy. Here we used placental vascular morphology measurements (depth and span) as well as the umbilical artery (UA) diameter of previously published studies on three different mouse strains (C57BL6/J, CD-1 and BALB/c), which were exposed to different conditions (combination antiretroviral therapy, chronic maternal hypoxia and malaria infection) at different embryonic days, to test the hypothesis that placental vascularization and specifically the UA size affect conceptus weight. Interaction of each study parameter with embryonic day, strain and exposure to treatments are studied to investigate the stability of the scaling relationships across and/or within strains and conditions. In addition, the effect of UA diameter on the placental growth measurements (depth and span) is studied. These results show that the power-law scaling relationship of conceptus weight and placental depth with the UA diameter is conserved across strains and conditions with the scaling exponent of approximately 3/8 and 5/8, respectively. By contrast, the relationship between conceptus weight and either the placental span or depth is different between strains and conditions, suggesting multiple mechanisms of vascular adaptation.

Sex as a determinant of disease severity and clinical outcome in febrile children under five presenting to a regional referral hospital in Uganda.

Sex and gender are well-established determinants of health in adult and adolescent populations in low resource settings. There are limited data on sex as a determinant of host response to disease and clinical outcome in febrile children in sub-Saharan Africa, where the risk of infection-related mortality is greatest. We examined sex differences and gender biases in health-seeking behavior, clinical care, biological response to infection, or outcome in a prospective observational cohort of febrile children under 5 years of age presenting to a regional referral hospital in Jinja, Uganda. Main outcomes (stratified by sex) were disease severity at presentation measured by clinical and biological parameters, clinical management (e.g., time to see a physician, treatment by diagnosis), and disease outcome (e.g., mortality). Clinical measures of disease severity included Lambaréné Organ Dysfunction Score (LODS), Signs of Inflammation in Children that Kill (SICK), and the Pediatric Early Death Index for Africa (PEDIA). Biological measures of disease severity were assessed using circulating markers of immune and endothelial activation associated with severe and fatal infections. Differences in outcome by sex were analyzed using bivariate analyses with Bonferroni correction for multiple comparisons. In this cohort of febrile patients admitted to hospital (n = 2049), malaria infection was common (59.2%). 15.9% of children presented with severe disease (LODS score ≥ 2). 97 children (4.7%) died, and most deaths (n = 83) occurred within 48 hours of hospital admission. Clinical measures of disease severity at presentation, clinical management, and outcome (e.g., mortality) did not differ by sex in children under five years of age. Host response to infection, as determined by endothelial and inflammatory mediators (e.g., sTREM1, Ang-2) quantified at hospital presentation, did not differ by sex. In this cohort of children under the age of five, sex was not a principal determinant of disease severity at hospital presentation, clinical management, disease outcome, or biological response to infection (p-values not significant for all comparisons, after Bonferroni correction). The results suggest that health seeking behavior by caregivers and clinical care in the hospital setting did not reflect a gender bias in this cohort.

Immune and endothelial activation markers and risk stratification of childhood pneumonia in Uganda: A secondary analysis of a prospective cohort study.

BACKGROUND: Despite the global burden of pneumonia, reliable triage tools to identify children in low-resource settings at risk of severe and fatal respiratory tract infection are lacking. This study assessed the ability of circulating host markers of immune and endothelial activation quantified at presentation, relative to currently used clinical measures of disease severity, to identify children with pneumonia who are at risk of death. METHODS AND FINDINGS: We conducted a secondary analysis of a prospective cohort study of children aged 2 to 59 months presenting to the Jinja Regional Hospital in Jinja, Uganda between February 2012 and August 2013, who met the Integrated Management of Childhood Illness (IMCI) diagnostic criteria for pneumonia. Circulating plasma markers of immune (IL-6, IL-8, CXCL-10/IP-10, CHI3L1, sTNFR1, and sTREM-1) and endothelial (sVCAM-1, sICAM-1, Angpt-1, Angpt-2, and sFlt-1) activation measured at hospital presentation were compared to lactate, respiratory rate, oxygen saturation, procalcitonin (PCT), and C-reactive protein (CRP) with a primary outcome of predicting 48-hour mortality. Of 805 children with IMCI pneumonia, 616 had severe pneumonia. Compared to 10 other immune and endothelial activation markers, sTREM-1 levels at presentation had the best predictive accuracy in identifying 48-hour mortality for children with pneumonia (AUROC 0.885, 95% CI 0.841 to 0.928; p = 0.03 to p < 0.001) and severe pneumonia (AUROC 0.870, 95% CI 0.824 to 0.916; p = 0.04 to p < 0.001). sTREM-1 was more strongly associated with 48-hour mortality than lactate (AUROC 0.745, 95% CI 0.664 to 0.826; p < 0.001), respiratory rate (AUROC 0.615, 95% CI 0.528 to 0.702; p < 0.001), oxygen saturation (AUROC 0.685, 95% CI 0.594 to 0.776; p = 0.002), PCT (AUROC 0.650, 95% CI 0.566 to 0.734; p < 0.001), and CRP (AUROC 0.562, 95% CI 0.472 to 0.653; p < 0.001) in cases of pneumonia and severe pneumonia. The main limitation of this study was the unavailability of radiographic imaging. CONCLUSIONS: In this cohort of Ugandan children, sTREM-1 measured at hospital presentation was a significantly better indicator of 48-hour mortality risk than other common approaches to risk stratify children with pneumonia. Measuring sTREM-1 at clinical presentation may improve the early triage, management, and outcome of children with pneumonia at risk of death. TRIAL REGISTRATION: The trial was registered at clinicaltrial.gov (NCT04726826).

Plasma concentrations of leptin at mid-pregnancy are associated with gestational weight gain among pregnant women in Tanzania: a prospective cohort study.

BACKGROUND: Gestational weight gain (GWG) has critical implications for maternal and child health. Inflammation and angiogenesis are implicated in various aspects of maternal metabolism that may play a role in gestational weight gain. The associations of inflammatory, angiogenic, and metabolic pathways with GWG are yet to be elucidated. This study evaluated associations between a panel of inflammatory, angiogenic, and metabolic proteins measured in mid-pregnancy and gestational weight gain. METHODS: Pregnant women were enrolled from Dar es Salaam, Tanzania, between 2001 and 2004. The participants were enrolled at mid-pregnancy (12 to 27 weeks of gestation) and followed up until delivery. This analysis focused on a cohort of 1002 women who were primigravid, had singleton live births, had longitudinal measures of gestational weight, and whose mid-pregnancy plasma samples underwent analysis for 18 proteins. RESULTS: Higher plasma concentrations of leptin (mean difference in GWG percent adequacy comparing highest with lowest quartiles: 10.24; 95% CI 3.31, 17.16; p-trend = 0.003) and chitinase-3-like protein-1 (CH3L1) (mean difference in GWG percent adequacy comparing highest with lowest quartiles: 7.02; 95% CI 0.31, 13.72; p-trend = 0.007) were associated with greater GWG in a dose-response pattern. Higher leptin concentrations were associated with a lower risk of inadequate GWG (risk ratio comparing highest with lowest quartiles: 0.77; 95% CI 0.65, 0.91; p-trend = 0.001) and a higher risk of excessive GWG (risk ratio comparing highest with lowest quartiles: 1.57; 95% CI 1.03, 2.39; p-trend = 0.03). Higher CH3L1 concentrations were associated with a higher risk of excessive GWG (p-trend = 0.007). The associations of leptin and CH3L1 with inadequate GWG were stronger during the second than the third trimester. The other 16 proteins examined were not significantly associated with GWG. CONCLUSIONS: Mid-pregnancy plasma leptin concentrations may be associated with GWG and have clinical predictive utility in identifying women at a higher risk of inadequate or excessive gestational weight gain.

Neurocognitive outcomes in Malawian children exposed to malaria during pregnancy: An observational birth cohort study.

BACKGROUND: Annually 125 million pregnancies are at risk of malaria infection. However, the impact of exposure to malaria in pregnancy on neurodevelopment in children is not well understood. We hypothesized that malaria in pregnancy and associated maternal immune activation result in neurodevelopmental delay in exposed offspring. METHODS AND FINDINGS: Between April 2014 and April 2015, we followed 421 Malawian mother-baby dyads (median [IQR] maternal age: 21 [19, 28] years) who were previously enrolled (median [IQR] gestational age at enrollment: 19.7 [17.9, 22.1] weeks) in a randomized controlled malaria prevention trial with 5 or 6 scheduled assessments of antenatal malaria infection by PCR. Children were evaluated at 12, 18, and/or 24 months of age with cognitive tests previously validated in Malawi: the Malawi Developmental Assessment Tool (MDAT) and the MacArthur-Bates Communicative Development Inventories (MCAB-CDI). We assessed the impact of antenatal malaria (n [%] positive: 240 [57.3]), placental malaria (n [%] positive: 112 [29.6]), and maternal immune activation on neurocognitive development in children. Linear mixed-effects analysis showed that children exposed to antenatal malaria between 33 and 37 weeks gestation had delayed language development across the 2-year follow-up, as measured by MCAB-CDI (adjusted beta estimate [95% CI], -7.53 [-13.04, -2.02], p = 0.008). Maternal immune activation, characterized by increased maternal sTNFRII concentration, between 33 and 37 weeks was associated with lower MCAB-CDI language score (adjusted beta estimate [95% CI], -8.57 [-13.09, -4.06], p < 0.001). Main limitations of this study include a relatively short length of follow-up and a potential for residual confounding that is characteristic of observational studies. CONCLUSIONS: This mother-baby cohort presents evidence of a relationship between malaria in pregnancy and neurodevelopmental delay in offspring. Malaria in pregnancy may be a modifiable risk factor for neurodevelopmental injury independent of birth weight or prematurity. Successful interventions to prevent malaria during pregnancy may reduce the risk of neurocognitive delay in children.

Malaria in Pregnancy and Adverse Birth Outcomes: New Mechanisms and Therapeutic Opportunities.

Malaria infection during pregnancy is associated with adverse birth outcomes but underlying mechanisms are poorly understood. Here, we discuss the impact of malaria in pregnancy on three pathways that are important regulators of healthy pregnancy outcomes: L-arginine-nitric oxide biogenesis, complement activation, and the heme axis. These pathways are not mutually exclusive, and they collectively create a proinflammatory, antiangiogenic milieu at the maternal-fetal interface that interferes with placental function and development. We hypothesize that targeting these host-response pathways would mitigate the burden of adverse birth outcomes attributable to malaria in pregnancy.

Early malaria infection, dysregulation of angiogenesis, metabolism and inflammation across pregnancy, and risk of preterm birth in Malawi: A cohort study.

BACKGROUND: Malaria in pregnancy is associated with adverse birth outcomes. However, the underlying mechanisms remain poorly understood. Tight regulation of angiogenic, metabolic, and inflammatory pathways are essential for healthy pregnancies. We hypothesized that malaria disrupts these pathways leading to preterm birth (PTB). METHODS AND FINDINGS: We conducted a secondary analysis of a randomized trial of malaria prevention in pregnancy conducted in Malawi from July 21, 2011, to March 18, 2013. We longitudinally assessed circulating mediators of angiogenic, metabolic, and inflammatory pathways during pregnancy in a cohort of HIV-negative women (n = 1,628), with a median age of 21 years [18, 25], and 562 (35%) were primigravid. Pregnancies were ultrasound dated, and samples were analyzed at 13 to 23 weeks (Visit 1), 28 to 33 weeks (Visit 2), and/or 34 to 36 weeks (Visit 3). Malaria prevalence was high; 70% (n = 1,138) had PCR-positive Plasmodium falciparum infection at least once over the course of pregnancy and/or positive placental histology. The risk of delivering preterm in the entire cohort was 20% (n = 304/1506). Women with malaria before 24 weeks gestation had a higher risk of PTB (24% versus 18%, p = 0.005; adjusted relative risk [aRR] 1.30, 95% confidence interval [CI] 1.04-1.63, p = 0.021); and those who were malaria positive only before week 24 had an even greater risk of PTB (28% versus 17%, p = 0.02; with an aRR of 1.67, 95% CI 1.20-2.30, p = 0.002). Using linear mixed-effects modeling, malaria before 24 weeks gestation was associated with altered kinetics of inflammatory (C-Reactive Protein [CRP], Chitinase 3-like protein-1 [CHI3L1], Interleukin 18 Binding Protein [IL-18BP], soluble Tumor Necrosis Factor receptor II [sTNFRII], soluble Intercellular Adhesion Molecule-1 [sICAM-1]), angiogenic (soluble Endoglin [sEng]), and metabolic mediators (Leptin, Angiopoietin-like 3 [Angptl3]) over the course of pregnancy (χ2 > 13.0, p ≤ 0.001 for each). Limitations include being underpowered to assess the impact on nonviable births, being unable to assess women who had not received any antimalarials, and, because of the exposure to antimalarials in the second trimester, there were limited numbers of malaria infections late in pregnancy. CONCLUSIONS: Current interventions for the prevention of malaria in pregnancy are initiated at the first antenatal visit, usually in the second trimester. In this study, we found that many women are already malaria-infected by their first visit. Malaria infection before 24 weeks gestation was associated with dysregulation of essential regulators of angiogenesis, metabolism, and inflammation and an increased risk of PTB. Preventing malaria earlier in pregnancy may reduce placental dysfunction and thereby improve birth outcomes in malaria-endemic settings.

The Impact of Infection in Pregnancy on Placental Vascular Development and Adverse Birth Outcomes.

Healthy fetal development is dependent on nutrient and oxygen transfer via the placenta. Optimal growth and function of placental vasculature is therefore essential to support in utero development. Vasculogenesis, the de novo formation of blood vessels, and angiogenesis, the branching and remodeling of existing vasculature, mediate the development and maturation of placental villi, which form the materno-fetal interface. Several lines of evidence indicate that systemic maternal infection and consequent inflammation can disrupt placental vasculogenesis and angiogenesis. The resulting alterations in placental hemodynamics impact fetal growth and contribute to poor birth outcomes including preterm delivery, small-for-gestational age (SGA), stillbirth, and low birth weight (LBW). Furthermore, pathways involved in maternal immune activation and placental vascularization parallel those involved in normal fetal development, notably neurovascular development. Therefore, immune-mediated disruption of angiogenic pathways at the materno-fetal interface may also have long-term neurological consequences for offspring. Here, we review current literature evaluating the influence of maternal infection and immune activation at the materno-fetal interface and the subsequent impact on placental vascular function and birth outcome. Immunomodulatory pathways, including chemokines and cytokines released in response to maternal infection, interact closely with the principal pathways regulating placental vascular development, including the angiopoietin-Tie-2, vascular endothelial growth factor (VEGF), and placental growth factor (PlGF) pathways. A detailed mechanistic understanding of how maternal infections impact placental and fetal development is critical to the design of effective interventions to promote placental growth and function and thereby reduce adverse birth outcomes.

Systemic inflammation is associated with malaria and preterm birth in women living with HIV on antiretrovirals and co-trimoxazole.

Women living with HIV (WLHIV) have an increased risk of malaria in pregnancy (MiP). It is unclear if MiP in WLHIV causes a systemic inflammatory response and increases the risk of adverse birth outcomes, especially for women receiving antiretroviral therapy (ART) and daily trimethoprim-sulfamethoxazole (TMP/SXT). We analyzed repeated plasma samples in a cohort of malaria-exposed Ugandan WLHIV receiving ART and daily TMP/SXT to examine changes in inflammatory markers across pregnancy and their association with birth outcomes. Concentrations of CHI3L1, CRP, IL-18BP, IL-6, sICAM-1, and sTNFR2 were quantified by ELISA in 1115 plasma samples collected over pregnancy from 326 women. MiP was associated with increased sTNFR2, sICAM-1 and IL-18BP concentrations across pregnancy. Women who delivered preterm had elevated concentrations of sTNFR2 and altered levels of IL-6 during pregnancy. Women with sTNFR2 concentrations in the highest quartile within 6 weeks of delivery had an increased relative risk of preterm birth. Our results indicate that despite daily TMP/SXT, MiP in WLHIV induced a systemic inflammatory response that was associated with an increased risk of preterm birth. These findings highlight the need for additional strategies to protect WLHIV from malaria infection in pregnancy to promote healthy outcomes for mother and child.

Perspective: L-arginine and L-citrulline Supplementation in Pregnancy: A Potential Strategy to Improve Birth Outcomes in Low-Resource Settings.

The available data support the hypothesis that L-arginine or L-citrulline supplementation would be suitable for implementation in resource-constrained settings and will enhance placental vascular development and improve birth outcomes. In resource-constrained settings, the rates of adverse birth outcomes, including fetal growth restriction, preterm birth, and low birth weight, are disproportionately high. Complications resulting from preterm birth are now the leading cause of mortality in children <5 y of age worldwide. Despite the global health burden of adverse birth outcomes, few effective interventions are currently available and new strategies are urgently needed, especially for low-resource settings. L-arginine is a nutritionally essential amino acid in pregnancy and an immediate precursor of nitric oxide. During pregnancy, placental and embryonic growth increases the demand for L-arginine, which can exceed endogenous synthesis of L-arginine from L-citrulline, necessitating increased dietary intake. In many low-resource settings, dietary intake of L-arginine in pregnancy is inadequate owing to widespread protein malnutrition and depletion of endogenous L-arginine due to maternal infections, in particular malaria. Here we examine the role of the L-arginine-nitric oxide biosynthetic pathway in pregnancy including placental vascular development and fetal growth. We review the evidence for the relations between altered L-arginine bioavailability and pregnancy outcomes, and strategies for arginine supplementation in pregnancy. Existing studies of L-arginine supplementation in pregnancy in high-resource settings have shown improved maternal and fetal hemodynamics, prevention of pre-eclampsia, and improved birth outcomes including higher birth weight and longer gestation. Arginine supplementation studies now need to be extended to pregnant women in low-resource settings, especially those at risk of malaria.

Integrated fever management: disease severity markers to triage children with malaria and non-malarial febrile illness.

Febrile symptoms in children are a leading cause of health-care seeking behaviour worldwide. The majority of febrile illnesses are uncomplicated and self-limited, without the need for referral or hospital admission. However, current diagnostic tools are unable to identify which febrile children have self-limited infection and which children are at risk of progressing to life-threatening infections, such as severe malaria. This paper describes the need for a simple community-based tool that can improve the early recognition and triage of febrile children, with either malarial or non-malarial illness, at risk of critical illness. The integration of a disease severity marker into existing malaria rapid diagnostic tests (RDT) could enable detection of children at risk of severe infection in the hospital and community, irrespective of aetiology. Incorporation of a disease severity marker could inform individualized management and early triage of children at risk of life-threatening infection. A child positive for both malaria and a disease severity marker could be prioritized for urgent referral/admission and parenteral therapy. A child positive for malaria and negative for a disease severity marker could be managed conservatively, as an out-patient, with oral anti-malarial therapy. An RDT with a disease severity marker could facilitate an integrated community-based approach to fever syndromes and improve early recognition, risk stratification, and prompt treatment of severe malaria and other life-threatening infections.

Malaria in pregnancy alters l-arginine bioavailability and placental vascular development.

Reducing adverse birth outcomes due to malaria in pregnancy (MIP) is a global health priority. However, there are few safe and effective interventions. l-Arginine is an essential amino acid in pregnancy and an immediate precursor in the biosynthesis of nitric oxide (NO), but there are limited data on the impact of MIP on NO biogenesis. We hypothesized that hypoarginemia contributes to the pathophysiology of MIP and that l-arginine supplementation would improve birth outcomes. In a prospective study of pregnant Malawian women, we show that MIP was associated with lower concentrations of l-arginine and higher concentrations of endogenous inhibitors of NO biosynthesis, asymmetric and symmetric dimethylarginine, which were associated with adverse birth outcomes. In a model of experimental MIP, l-arginine supplementation in dams improved birth outcomes (decreased stillbirth and increased birth weight) compared with controls. The mechanism of action was via normalized angiogenic pathways and enhanced placental vascular development, as visualized by placental microcomputerized tomography imaging. These data define a role for dysregulation of NO biosynthetic pathways in the pathogenesis of MIP and support the evaluation of interventions to enhance l-arginine bioavailability as strategies to improve birth outcomes.

Estradiol Levels Are Altered in Human Immunodeficiency Virus-Infected Pregnant Women Randomized to Efavirenz-Versus Lopinavir/Ritonavir-Based Antiretroviral Therapy.

Background: Combination antiretroviral therapy (cART) use in pregnancy has been associated with hormonal dysregulation. We performed a secondary retrospective analysis of longitudinal progesterone and estradiol levels in pregnancy using specimens from the Protease Inhibitors to Reduce Malaria Morbidity in HIV-infected Pregnant Women study, which randomized Ugandan human immunodeficiency virus (HIV)-infected ART-naive women to initiate either lopinavir/ritonavir (LPV/r)-based or efavirenz (EFV)-based cART. Methods: Three hundred twenty-six women (160 randomized to the EFV arm and 166 women to the LPV/r arm) with at least 1 plasma sample collected during pregnancy were included. Enrollment samples collected prior to cART initiation were used as a cART-naive comparator group. Hormone levels were quantified by enzyme-linked immunosorbent assay. Results: Estradiol levels were differentially affected by the 2 cART regimens. Exposure to LPV/r was associated with an increase in estradiol (P < .0001), whereas exposure to EFV was associated with a decrease in estradiol (P < .0001), relative to the cART-naive gestationally matched comparator group. Lower estradiol levels correlated with small for gestational age (SGA) (P = .0019) and low birth weight (P = .019) in the EFV arm, while higher estradiol levels correlated with SGA in the LPV/r arm (P = .027). Although progesterone levels were similar between treatment arms, we observed an association between SGA and lower progesterone in the LPV/r arm (P = .04). No association was observed between hormone levels and preterm birth in either arm. Levels of progesterone and estradiol were lower in cases of stillbirth, and levels of both hormones declined immediately prior to stillbirth in 5 of 8 cases. Conclusions: Combination ART regimens differentially affect estradiol levels in pregnancy, a hormone critical to the maintenance of a healthy pregnancy. Identifying cART regimens that minimize perinatal HIV transmission without contributing to hormonal dysregulation represents an urgent public health priority. Clinical Trials Registration: NCT00993031.