Risk-stratification of febrile African children at risk of sepsis using sTREM-1 as basis for a rapid triage test

Innovative strategies for the surveillance, prevention, and management of pediatric infections applied to low-income settings

INTRODUCTION

Infectious diseases still cause a significant burden of morbidity and mortality among children in low- and middle-income countries (LMICs). There are ample opportunities for innovation in surveillance, prevention, and management, with the ultimate goal of improving survival.

AREAS COVERED

This review discusses the current status in the use and development of innovative strategies for pediatric infectious diseases in LMICs by focusing on surveillance, diagnosis, prevention, and management. Topics covered are: Minimally Invasive Tissue Sampling as a technique to accurately ascertain the cause of death; Genetic Surveillance to trace the pathogen genomic diversity and emergence of resistance; Artificial Intelligence as a multidisciplinary tool; Portable noninvasive imaging methods; and Prognostic Biomarkers to triage and risk stratify pediatric patients.

EXPERT OPINION

To overcome the specific hurdles in child health for LMICs, some innovative strategies appear at the forefront of research. If the development of these next-generation tools remains focused on accessibility, sustainability and capacity building, reshaping epidemiological surveillance, diagnosis, and treatment in LMICs, can become a reality and result in a significant public health impact. Their integration with existing healthcare infrastructures may revolutionize disease detection and surveillance, and improve child health and survival.

Angiogenesis-associated pathways play critical roles in neonatal sepsis outcomes

Neonatal sepsis is a major cause of childhood mortality. Limited diagnostic tools and mechanistic insights have hampered our abilities to develop prophylactic or therapeutic interventions. Biomarkers in human neonatal sepsis have been repeatedly identified as associated with dysregulation of angiopoietin signaling and altered arachidonic acid metabolism. We here provide the mechanistic evidence in support of the relevance for these observations. Angiopoetin-1 (Ang-1), which promotes vascular integrity, was decreased in blood plasma of human and murine septic newborns. In preclinical models, administration of Ang-1 provided prophylactic protection from septic death. Arachidonic acid metabolism appears to be functionally connected to Ang-1 via reactive oxygen species (ROS) with a direct role of nitric oxide (NO). Strengthening this intersection via oral administration of arachidonic acid and/or the NO donor L-arginine provided prophylactic as well as therapeutic protection from septic death while also increasing plasma Ang-1 levels among septic newborns. Our data highlight that targeting angiogenesis-associated pathways with interventions that increase Ang-1 activity directly or indirectly through ROS/eNOS provide promising avenues to prevent and/or treat severe neonatal sepsis.

sTREM-1: A Biomarker of Mortality in Severe Malaria Impacted by Acute Kidney Injury

BACKGROUND

Malaria is an important cause of mortality in African children. Identification of biomarkers to identify children at risk of mortality has the potential to improve outcomes.

METHODS

We evaluated 11 biomarkers of host response in 592 children with severe malaria. The primary outcome was biomarker performance for predicting mortality. Biomarkers were evaluated using receiver operating characteristic (ROC) curve analysis comparing the area under the ROC curve (AUROC).

RESULTS

Mortality was 7.3% among children in the study with 72% of deaths occurring within 24 hours of admission. Among the candidate biomarkers, soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) had the highest AUROC (0.78 [95% confidence interval, .70-.86]), outperforming several other biomarkers including C-reactive protein and procalcitonin. sTREM-1 was the top-performing biomarker across prespecified subgroups (malaria definition, site, sex, nutritional status, age). Using established cutoffs, we evaluated mortality across sTREM-1 risk zones. Among children with acute kidney injury, 39.9% of children with a critical-risk sTREM-1 result had an indication for dialysis. When evaluated relative to a disease severity score, sTREM-1 improved mortality prediction (difference in AUROC, P = .016).

CONCLUSIONS

sTREM-1 is a promising biomarker to guide rational allocation of clinical resources and should be integrated into clinical decision support algorithms, particularly when acute kidney injury is suspected.

Advances in sepsis biomarkers

Sepsis, a dysregulated host immune response to an infectious agent, significantly increases morbidity and mortality for hospitalized patients worldwide. This chapter reviews (1) the basic principles of infectious diseases, pathophysiology and current definition of sepsis, (2) established sepsis biomarkers such lactate, procalcitonin and C-reactive protein, (3) novel, newly regulatory-cleared/approved biomarkers, such as assays that evaluate white blood cell properties and immune response molecules, and (4) emerging biomarkers and biomarker panels to highlight future directions and opportunities in the diagnosis and management of sepsis.

Adjunctive rosiglitazone treatment for severe pediatric malaria: A randomized placebo-controlled trial in Mozambican children

OBJECTIVES

We tested the hypothesis that adjunctive rosiglitazone treatment would reduce levels of circulating angiopoietin-2 (Angpt-2) and improve outcomes of Mozambican children with severe malaria.

METHODS

A randomized, double-blind, placebo-controlled trial of rosiglitazone vs placebo as adjunctive treatment to artesunate in children with severe malaria was conducted. A 0.045 mg/kg/dose of rosiglitazone or matching placebo were administered, in addition to standard of malaria care, twice a day for 4 days. The primary endpoint was the rate of decline of Angpt-2 over 96 hours. Secondary outcomes included the longitudinal dynamics of angiopoietin-1 (Angpt-1) and the Angpt-2/Angpt-1 ratio over 96 hours, parasite clearance kinetics, clinical outcomes, and safety metrics.

RESULTS

Overall, 180 children were enrolled; 91 were assigned to rosiglitazone and 89 to placebo. Children who received rosiglitazone had a steeper rate of decline of Angpt-2 over the first 96 hours of hospitalization compared to children who received placebo; however, the trend was not significant (P = 0.28). A similar non-significant trend was observed for Angpt-1 (P = 0.65) and the Angpt-2/Angpt-1 ratio (P = 0.34). All other secondary and safety outcomes were similar between groups (P >0.05).

CONCLUSION

Adjunctive rosiglitazone at this dosage was safe and well tolerated but did not significantly affect the longitudinal kinetics of circulating Angpt-2.

Rationale and design of the pullback pressure gradient (PPG) global registry

INTRODUCTION

Diffuse disease has been identified as one of the main reasons leading to low post-PCI fractional flow reserve (FFR) and residual angina after PCI. Coronary pressure pullbacks allow for the evaluation of hemodynamic coronary artery disease (CAD) patterns. The pullback pressure gradient (PPG) is a novel metric that quantifies the distribution and magnitude of pressure losses along the coronary artery in a focal-to-diffuse continuum.

AIM

The primary objective is to determine the predictive capacity of the PPG for post-PCI FFR.

METHODS

This prospective, large-scale, controlled, investigator-initiated, multicenter study is enrolling patients with at least 1 lesion in a major epicardial vessel with a distal FFR ≤ 0.80 intended to be treated by PCI. The study will include 982 subjects. A standardized physiological assessment will be performed pre-PCI, including the online calculation of PPG from FFR pullbacks performed manually. PPG quantifies the CAD pattern by combining several parameters from the FFR pullback curve. Post-PCI physiology will be recorded using a standardized protocol with FFR pullbacks. We hypothesize that PPG will predict optimal PCI results (post-PCI FFR ≥ 0.88) with an area under the ROC curve (AUC) ≥ 0.80. Secondary objectives include patient-reported and clinical outcomes in patients with focal vs. diffuse CAD defined by the PPG. Clinical follow-up will be collected for up to 36 months, and an independent clinical event committee will adjudicate events.

RESULTS

Recruitment is ongoing and is expected to be completed in the second half of 2023.

CONCLUSION

This international, large-scale, prospective study with pre-specified powered hypotheses will determine the ability of the preprocedural PPG index to predict optimal revascularization assessed by post-PCI FFR. In addition, it will evaluate the impact of PPG on treatment decisions and the predictive performance of PPG for angina relief and clinical outcomes.

Low lymphocyte to high-density lipoprotein ratio predicts mortality in sepsis patients

Background

The lymphocyte-to-high-density lipoprotein (HDL) ratio (LHR) is associated with both inflammation and immunity, and may have the potential to predict the prognosis of sepsis. Our study aimed to evaluate the relationship between LHR and sepsis-related mortality.

Methods

We collected data from the Medical Information Mart for Intensive Care IV (MIMIC-IV, version 2.2) database by targeting patients who met the Sepsis-3 criteria and recorded the absolute values of lymphocytes and HDL after admission. We then used restricted cubic splines based on logistic regression to simulate the relationship between the LHR and 90-day mortality. Subsequently, the hazardous threshold was derived based on the mortality curve, and further evaluations were performed using different methods and data sources for hazardous threshold.

Results

We ultimately included 1027 eligible patients from the MIMIC-IV database and described the nonlinear relationship between LHR and 90-day mortality. Based on the curve, an LHR of ≤ 0.6 indicated harmful threshold, and the odds ratio for mortality was 1.74 (P=0.001). The outperforming hazard was particularly marked in patients with chronic lung disease and remained consistent after adjusting for baseline data and validating multiple data sources.

Conclusions

The LHR has prognostic value in patients with sepsis, and an LHR ≤ 0.6 is a deleterious load that increases mortality.

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.

Pediatric Malaria with Respiratory Distress: Prognostic Significance of Point-of-Care Lactate

Respiratory distress (RD) in pediatric malaria portends a grave prognosis. Lactic acidosis is a biomarker of severe disease. We investigated whether lactate, measured at admission using a handheld device among children hospitalized with malaria and RD, was predictive of subsequent mortality. We performed a pooled analysis of Ugandan children under five years of age hospitalized with malaria and RD from three past studies. In total, 1324 children with malaria and RD (median age 1.4 years, 46% female) from 21 health facilities were included. Median lactate level at admission was 4.6 mmol/L (IQR 2.6–8.5) and 586 patients (44%) had hyperlactatemia (lactate > 5 mmol/L). The mortality was 84/1324 (6.3%). In a mixed-effects Cox proportional hazard model adjusting for age, sex, clinical severity score (fixed effects), study, and site (random effects), hyperlactatemia was associated with a 3-fold increased hazard of death (aHR 3.0, 95%CI 1.8–5.3, p < 0.0001). Delayed capillary refill time (τ = 0.14, p < 0.0001), hypotension (τ = −0.10, p = 0.00049), anemia (τ = −0.25, p < 0.0001), low tissue oxygen delivery (τ = −0.19, p < 0.0001), high parasite density (τ = 0.10, p < 0.0001), and acute kidney injury (p = 0.00047) were associated with higher lactate levels. In children with malaria and RD, bedside lactate may be a useful triage tool, predictive of mortality.

Circulating protein and lipid markers of early sepsis diagnosis and prognosis: a scoping review

PURPOSE OF REVIEW

Sepsis is the extreme response to infection associated with high mortality, yet reliable biomarkers for its identification and stratification are lacking.

RECENT FINDINGS

Our scoping review of studies published from January 2017 to September 2022 that investigated circulating protein and lipid markers to inform non-COVID-19 sepsis diagnosis and prognosis identified interleukin (IL)-6, IL-8, heparin-binding protein (HBP), and angiopoietin-2 as having the most evidence. Biomarkers can be grouped according to sepsis pathobiology to inform biological data interpretation and four such physiologic processes include: immune regulation, endothelial injury and coagulopathy, cellular injury, and organ injury. Relative to proteins, the pleiotropic effects of lipid species' render their categorization more difficult. Circulating lipids are relatively less well studied in sepsis, however, low high-density lipoprotein (HDL) is associated with poor outcome.

SUMMARY

There is a lack of robust, large, and multicenter studies to support the routine use of circulating proteins and lipids for sepsis diagnosis or prognosis. Future studies will benefit from standardizing cohort design as well as analytical and reporting strategies. Incorporating biomarker dynamic changes and clinical data in statistical modeling may improve specificity for sepsis diagnosis and prognosis. To guide future clinical decisions at the bedside, point-of-care circulating biomarker quantification is needed.

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.

Diagnosis of cerebral malaria: Tools to reduce Plasmodium falciparum associated mortality

Cerebral malaria (CM) is a major cause of mortality in Plasmodium falciparum (Pf) infection and is associated with the sequestration of parasitised erythrocytes in the microvasculature of the host's vital organs. Prompt diagnosis and treatment are key to a positive outcome in CM. However, current diagnostic tools remain inadequate to assess the degree of brain dysfunction associated with CM before the window for effective treatment closes. Several host and parasite factor-based biomarkers have been suggested as rapid diagnostic tools with potential for early CM diagnosis, however, no specific biomarker signature has been validated. Here, we provide an updated review on promising CM biomarker candidates and evaluate their applicability as point-of-care tools in malaria-endemic areas.

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.

MICROVASCULAR ENDOTHELIAL ACTIVATION/DYSFUNCTION AND DYSREGULATION OF THE ANGIOPOIETIN-TIE2 SYSTEM IN THE PATHOGENESIS OF LIFE-THREATENING INFECTIONS

Microvascular endothelial activation/dysfunction has emerged as an important mechanistic pathophysiological process in the development of morbidity and mortality in life-threatening infections. The angiopoietin-Tie2 system plays an integral role in the regulation of microvascular endothelial integrity. Angiopoietin-1 (Ang-1), produced by platelets and pericytes, is the cognate agonistic ligand for Tie2, promoting endothelial quiescence and inhibiting microvascular leak. Angiopoietin-2 (Ang-2), released from activated endothelial cells in Weibel-Palade bodies, competes with Ang-1 for binding to Tie-2, thereby promoting endothelial activation/dysfunction and microvascular leak. In healthy homeostasis, levels of Ang-1 far exceed Ang-2 in circulating serum/plasma. In diseases associated with systemic inflammation, Ang-1 falls and Ang-2 rises (i.e., Ang-1/2 dysregulation). Our research has shown that Ang-1/2 dysregulation is a prominent feature in a number of life-threatening infections and critical illnesses, including sepsis, cerebral malaria, COVID-19, streptococcal toxic shock syndrome (STSS), hemolytic-uremic syndrome (HUS), dengue, and CAR T-cell-associated neurotoxicity. Further work has implicated Ang-1/2 dysregulation in the development of end-organ injury, including acute lung injury/ARDS, acute kidney injury (AKI), and blood-brain-barrier (BBB) breakdown. Current studies are focused in three areas: (a) translation of Ang-1 and -2 as clinically informative prognostic and "theranostic" biomarkers in critically ill individuals; (b) incorporation of Ang-1/2 assays in a point of care device for clinical triage decision making; and (c) development of an engineered Ang-1 super agonist nanoparticle as a novel pathogen-agnostic therapeutic to prevent and/or mitigate end-organ dysfunction in individuals with life-threatening infections and critical illnesses associated with systemic inflammation.

Biomarkers of Intestinal Injury and Dysfunction: Adding New Possibilities to Current Methods for Risk Stratification of Children with Malaria Disease

Malaria remains, in 2022, a major cause of pediatric preventable mortality, with its major burden disproportionately circumscribed to sub-Saharan African countries. Although only ~1 to 2% of malaria cases can be considered severe and potentially life threatening, it is often challenging to identify them so as to prioritize adequate health care and resources. In a recent investigation, M. L. Sarangam, R. Namazzi, D. Datta, C. Bond, et al. (mBio 13:e01325-22, 2022, https://journals.asm.org/doi/10.1128/mbio.01325-22) studied intestinal barrier dysfunction and injury in Ugandan children hospitalized with severe malaria and in healthy community controls. By measuring circulating levels of four different and complementary biomarkers of gut barrier dysfunction and microbial translocation, they demonstrated that intestinal injury is common in pediatric severe malaria (18% of all cases) and is associated with increased mortality, acute kidney injury, acidosis, and endothelial activation. This commentary discusses the prognostic implications of these results, knowledge gaps that remain to be filled, and how findings could be potentially translated into effective interventions to improve outcomes in children with malaria.

Performance of host-response biomarkers to risk-stratify children with pneumonia in Bhutan

Pneumonia is the leading cause of post-neonatal death amongst children under five years of age; however, there is no simple triage tool to identify children at risk of progressing to severe and fatal disease. Such a tool could assist for early referral and prioritization of care to improve outcomes and enhance allocation of scarce resources. We compared the performance of inflammatory and endothelial activation markers in addition to clinical signs or scoring scales to risk-stratify children hospitalized with pneumonia at the national referral hospital of Bhutan with the goal of predicting clinical outcome. Of 118 children, 31 evolved to a poor prognosis, defined as either mortality, admission in the paediatric intensive care unit, requirement of chest drainage or requirement of more than five days of oxygen therapy. Soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) was the best performing biomarker and performed better than clinical parameters. sTREM-1 levels upon admission had good predictive accuracy to identify children with pneumonia at risk of poor prognosis. Our findings confirm that immune and endothelial activation markers could be proactively used at first encounter as risk-stratification and clinical decision-making tools in children with pneumonia; however, further external validation is needed.

Intestinal Injury in Ugandan Children Hospitalized With Malaria

BACKGROUND

Severe malaria is associated with multiple organ dysfunction syndrome (MODS), which may involve the gastrointestinal tract.

METHODS

In a prospective cohort study in Uganda, we measured markers of intestinal injury (intestinal fatty-acid binding protein [I-FABP] and zonula occludens-1 [ZO-1]) and microbial translocation (lipopolysaccharide binding protein [LBP] and soluble complement of differentiation 14 [sCD14]) among children admitted with malaria. We examined their association with biomarkers of inflammation, endothelial activation, clinical signs of hypoperfusion, organ injury, and mortality.

RESULTS

We enrolled 523 children (median age 1.5 years, 46% female, 7.5% mortality). Intestinal FABP was above the normal range (≥400 pg/mL) in 415 of 523 patients (79%). Intestinal FABP correlated with ZO-1 (ρ = 0.11, P = .014), sCD14 (ρ = 0.12, P = .0046) as well as markers of inflammation and endothelial activation. Higher I-FABP levels were associated with lower systolic blood pressure (ρ = -0.14, P = .0015), delayed capillary refill time (ρ = 0.17, P = .00011), higher lactate level (ρ = 0.40, P < .0001), increasing stage of acute kidney injury (ρ = 0.20, P = .0034), and coma (P < .0001). Admission I-FABP levels ≥5.6 ng/mL were associated with a 7.4-fold higher relative risk of in-hospital death (95% confidence interval, 1.4-11, P = .0016).

CONCLUSIONS

Intestinal injury occurs commonly in children hospitalized with malaria and is associated with microbial translocation, systemic inflammation, tissue hypoperfusion, MODS, and fatal outcome.

Biochemical characteristics of patients with imported malaria

Objectives

This study aimed to investigate the clinical and biochemical profiles of patients with imported malaria infection between 1 January 2011 and 30 April 2022 and admitted to the Fourth People’s Hospital of Nanning.

Methods

This cohort study enrolled 170 patients with conformed imported malaria infection. The clinical and biochemical profiles of these participants were analyzed with malaria parasite clearance, and signs and symptoms related to malaria disappearance were defined as the primary outcome. A multivariable logistic regression model was used to evaluate the odds ratios (ORs) with 95% confidence intervals (CIs) for cerebral malaria. The Cox model was used to estimate the hazard ratios (HRs) with 95% CIs for parasite clearance.

Results

Adenosine deaminase and parasitemia were found to be independent risk factors for severe malaria in patients with imported malaria (OR = 1.0088, 95% CI: 1.0010–1.0167, p = 0.0272 and OR = 2.0700, 95% CI: 1.2584–3.4050, p = 0.0042, respectively). A 0.5–standard deviation (SD) increase of variation for urea (HR = 0.6714, 95% CI: 0.4911–0.9180), a 0.5-SD increase of variation for creatinine (HR = 0.4566, 95% CI: 0.2762–0.7548), a 0.25-SD increase of variation for albumin (HR = 0.4947, 95% CI: 0.3197–0.7653), a 0.25-SD increase of variation for hydroxybutyrate dehydrogenase (HR = 0.6129, 95% CI: 0.3995–0.9402), and a 1.0-SD increase of variation for ferritin (HR = 0.5887, 95% CI: 0.3799–0.9125) were associated with a higher risk for increased parasite clearance duration than a low-level change.

Conclusions

Aspartate aminotransferase, urea, creatinine, albumin, hydroxybutyrate dehydrogenase, and ferritin are useful biochemical indicators in routine clinical practice to evaluate prognosis for imported malaria.

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).

Blackwater fever and acute kidney injury in children hospitalized with an acute febrile illness: pathophysiology and prognostic significance

BACKGROUND

Acute kidney injury (AKI) and blackwater fever (BWF) are related but distinct renal complications of acute febrile illness in East Africa. The pathogenesis and prognostic significance of BWF and AKI are not well understood.

METHODS

A prospective observational cohort study was conducted to evaluate the association between BWF and AKI in children hospitalized with an acute febrile illness. Secondary objectives were to examine the association of AKI and BWF with (i) host response biomarkers and (ii) mortality. AKI was defined using the Kidney Disease: Improving Global Outcomes criteria and BWF was based on parental report of tea-colored urine. Host markers of immune and endothelial activation were quantified on admission plasma samples. The relationships between BWF and AKI and clinical and biologic factors were evaluated using multivariable regression.

RESULTS

We evaluated BWF and AKI in 999 children with acute febrile illness (mean age 1.7 years (standard deviation 1.06), 55.7% male). At enrollment, 8.2% of children had a history of BWF, 49.5% had AKI, and 11.1% had severe AKI. A history of BWF was independently associated with 2.18-fold increased odds of AKI (95% CI 1.15 to 4.16). When examining host response, severe AKI was associated with increased immune and endothelial activation (increased CHI3L1, sTNFR1, sTREM-1, IL-8, Angpt-2, sFlt-1) while BWF was predominantly associated with endothelial activation (increased Angpt-2 and sFlt-1, decreased Angpt-1). The presence of severe AKI, not BWF, was associated with increased risk of in-hospital death (RR, 2.17 95% CI 1.01 to 4.64) adjusting for age, sex, and disease severity.

CONCLUSIONS

BWF is associated with severe AKI in children hospitalized with a severe febrile illness. Increased awareness of AKI in the setting of BWF, and improved access to AKI diagnostics, is needed to reduce disease progression and in-hospital mortality in this high-risk group of children through early implementation of kidney-protective measures.

Pathophysiology of Acute Kidney Injury in Malaria and Non-Malarial Febrile Illness: A Prospective Cohort Study

Acute kidney injury (AKI) is a life-threatening complication. Malaria and sepsis are leading causes of AKI in low-and-middle-income countries, but its etiology and pathogenesis are poorly understood. A prospective observational cohort study was conducted to evaluate pathways of immune and endothelial activation in children hospitalized with an acute febrile illness in Uganda. The relationship between clinical outcome and AKI, defined using the Kidney Disease: Improving Global Outcomes criteria, was investigated. The study included 967 participants (mean age 1.67 years, 44.7% female) with 687 (71.0%) positive for malaria by rapid diagnostic test and 280 (29.1%) children had a non-malarial febrile illness (NMFI). The frequency of AKI was higher in children with NMFI compared to malaria (AKI, 55.0% vs. 46.7%, p = 0.02). However, the frequency of severe AKI (stage 2 or 3 AKI) was comparable (12.1% vs. 10.5%, p = 0.45). Circulating markers of both immune and endothelial activation were associated with severe AKI. Children who had malaria and AKI had increased mortality (no AKI, 0.8% vs. AKI, 4.1%, p = 0.005), while there was no difference in mortality among children with NMFI (no AKI, 4.0% vs. AKI, 4.6%, p = 0.81). AKI is a common complication in children hospitalized with acute infections. Immune and endothelial activation appear to play central roles in the pathogenesis of AKI.