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.

A severe case of Plasmodium falciparum malaria in a traveler returning from Kazakhstan, a malaria-free country

Following a two-weeks trip to Kazakhstan, a 42-year-old woman presented at the emergency department in Germany with fever, headache, nausea, and neurological symptoms. An infection with Plasmodium falciparum was rapidly diagnosed. The patient was immediately treated with intravenous artesunate and transferred to an intensive care unit. The initial parasite density was as high as 30% infected erythrocytes with 845880 parasites/µL. Since Kazakhstan was declared malaria-free in 2012, molecular testing for Plasmodium has been initiated to identify a possible origin. Genotyping of the msp-1 gene and microsatellite markers showed that the parasites are of African origin, with two different alleles indicating a polyclonal infection. After a hospitalization of 10 days, the patient was discharged in good health. Overall, our results emphasize that malaria must be on the list of differential diagnoses for patients with fever of unknown origin, even if they come from countries where malaria does not commonly occur.

From GWAS to functional variants: ARL14 cis-regulatory variants are associated with severe malaria

BACKGROUND

GWAS have identified several non-functional tagSNPs associated with severe malaria. We hypothesized that causal SNPs could play a significant role in severe malaria by altering promoter or enhancer activity. Here, we sought to identify such regulatory SNPs.

METHODS

SNPs in linkage disequilibrium with tagSNPs associated with severe malaria were identified and were further annotated using FUMA. Then, SNPs were prioritized using IW-scoring method to identify regulatory ones. Gene reporter assays were performed to assess the regulatory effect of a region containing candidates. The association between SNPs and severe malaria was assessed using logistic regression models in a Senegalese cohort.

RESULTS

Among 418 SNPs, the best candidates were rs116525449 and rs79644959, which were in full disequilibrium between them, and located within the ARL14 promoter. Our gene reporter assay results revealed that the region containing the SNPs exhibited cell-specific promoter or enhancer activity, while the SNPs influenced promoter activity. We detected an association between severe malaria and those two SNPs using the overdominance model and we replicated the association of severe malaria with the tagSNP rs116423146.

CONCLUSIONS

We suggest that these SNPs regulate ARL14 expression in immune cells and the presentation of antigens to T lymphocytes, thus influencing severe malaria development.

Prevalence and risk factors of gross neurologic deficits in children after severe malaria: a systematic review protocol

Background

Children exposed to severe malaria may recover with gross neurologic deficits (GND). Several risk factors for GND after cerebral malaria (CM), the deadliest form of severe malaria, have been identified in children. However, there is inconsistency between previously reported and more recent findings. Although CM patients are the most likely group to develop GND, it is not clear if other forms of severe malaria (non-CM) may also contribute to the malaria related GND. The aim of this systematic review is to synthesize evidence on the prevalence and risk factors for GND in children following CM and map the changes in patterns over time. In addition, this review will synthesize evidence on the reported prevalence and risk factors of gross neurologic deficits following other forms of severe malaria.

Methods

The systematic review will be conducted according to recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols (PRISMA-P). Relevant research articles will be identified using relevant search terms from the following databases: MEDLINE, Embase, Web of Science and Global Index Medicus (GIM). The articles will be screened at title and abstract, then at full text for inclusion using a priori eligibility criteria. Data extraction will be done using a tool developed and optimized in Excel spreadsheet. Risk of bias assessment will be done using appropriate tools including ROBINS-E ('Risk Of Bias In Non-randomized Studies of Exposure') tool, while publication bias will be assessed using funnel plot. A random-effects meta-analysis and structured narrative synthesis of the outcomes will be performed and results presented.

Discussion

Findings from this systematic review will inform policy makers on planning, design and implementation of interventions targeting the treatment and rehabilitation of GND following severe malaria in children.

Systematic review registration

The protocol is registered in the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42022297109.

Exploring adjunctive therapies for cerebral malaria

Cerebral malaria (CM) is one of the most severe complications of malaria infection characterized by coma and neurological effects. Despite standardized treatment of malaria infection with artemisinin-based combination therapies (ACT), the mortality rate is still high, and it primarily affects pediatric patients. ACT reduces parasitemia but fails to adequately target the pathogenic mechanisms underlying CM, including blood-brain-barrier (BBB) disruption, endothelial activation/dysfunction, and hyperinflammation. The need for adjunctive therapies to specifically treat this form of severe malaria is critical as hundreds of thousands of people continue to die each year from this disease. Here we present a summary of some potential promising therapeutic targets and treatments for CM, as well as some that have been tested and deemed ineffective or, in some cases, even deleterious. Further exploration into these therapeutic agents is warranted to assess the effectiveness of these potential treatments for CM patients.

Enhanced Antimalarial and Antisequestration Activity of Methoxybenzenesulfonate-Modified Biopolymers and Nanoparticles for Tackling Severe Malaria

Severe malaria is a life-threatening condition that is associated with a high mortality. Severe Plasmodium falciparum infections are mediated primarily by high parasitemia and binding of infected red blood cells (iRBCs) to the blood vessel endothelial layer, a process known as sequestration. Here, we show that including the 5-amino-2-methoxybenzenesulfonate (AMBS) chemical modification in soluble biopolymers (polyglutamic acid and heparin) and poly(acrylic acid)-exposing nanoparticles serves as a universal tool to introduce a potent parasite invasion inhibitory function in these materials. Importantly, the modification did not add or eliminated (for heparin) undesired anticoagulation activity. The materials protected RBCs from invasion by various parasite strains, employing both major entry pathways. Two further P. falciparum strains, which either expose ligands for chondroitin sulfate A (CSA) or intercellular adhesion molecule 1 (ICAM-1) on iRBCs, were tested in antisequestration assays due to their relevance in placental and cerebral malaria, respectively. Antisequestration activity was found to be more efficacious with nanoparticles vs gold-standard soluble biopolymers (CSA and heparin) against both strains, when tested on receptor-coated dishes. The nanoparticles also efficiently inhibited and reversed the sequestration of iRBCs on endothelial cells. First, the materials described herein have the potential to reduce the parasite burden by acting at the key multiplication stage of reinvasion. Second, the antisequestration ability could help remove iRBCs from the blood vessel endothelium, which could otherwise cause vessel obstruction, which in turn can lead to multiple organ failure in severe malaria infections. This approach represents a further step toward creation of adjunctive therapies for this devastating condition to reduce morbidity and mortality.

Clinico-epidemiological profiles & outcome of severe malaria in children under-five in the tribal area of Kalahandi, Odisha

BACKGROUND OBJECTIVES

Severe malaria is a cause of excess mortality and morbidity in children in malaria-endemic areas where indigenous people live. Currently, available reports are all from secondary or tertiary care hospitals across India and some African countries. The objective of this study was to assess the clinical and epidemiological profiles of children under five years in two primary care health centres located in tribal-dominant Thuamul Rampur Block of Kalahandi district, Odisha. The outcome of management of severe malaria in these children was also assessed.

METHODS

A retrospective review of case records of children under five years of age diagnosed and admitted with severe malaria in two non-governmental primary care facilities between 2017 and 2022, was undertaken.

RESULTS

There was a declining trend in malaria cases documented in primary care health facilities between January 2017 and June 2022. Of the 4858 cases recorded, 242 (4.9%) had severe malaria, of whom 70.7 per cent (n=171) were children under 5 yr. The median age of the study children was 24 months (16-36). Children aged 1-2 yr had a significantly higher risk of malaria. The majority were tribals (87%), more than half the children presented with neurological manifestations (64.4%), and 49.6 per cent had respiratory manifestations, while 20.5 per cent had severe anaemia (Hb <5 g/dl). Most, 167 (97.7%) severe malaria was due to Plasmodium falciparum. Thirty-two percent of children were severely wasted (WHZ < -3 SD) and 28 per cent were moderately wasted (WHZ <-2 SD). There was no fatality among the 171 children who were managed for severe malaria in the two primary care facilities.

INTERPRETATION CONCLUSIONS

In high endemic areas severe malaria is predominantly a disease of under-five children and is caused by P. falciparum. Clinical manifestations of severe malaria in children can be varied and life-threatening. Primary health facilities can manage severe malaria successfully, thereby reducing child mortality. Effective collaboration between malaria control and nutrition intervention programmes is essential for appropriate case management.

Pathogenicity and virulence of malaria: Sticky problems and tricky solutions

Infections with Plasmodium falciparum and Plasmodium vivax cause over 600,000 deaths each year, concentrated in Africa and in young children, but much of the world's population remain at risk of infection. In this article, we review the latest developments in the immunogenicity and pathogenesis of malaria, with a particular focus on P. falciparum, the leading malaria killer. Pathogenic factors include parasite-derived toxins and variant surface antigens on infected erythrocytes that mediate sequestration in the deep vasculature. Host response to parasite toxins and to variant antigens is an important determinant of disease severity. Understanding how parasites sequester, and how antibody to variant antigens could prevent sequestration, may lead to new approaches to treat and prevent disease. Difficulties in malaria diagnosis, drug resistance, and specific challenges of treating P. vivax pose challenges to malaria elimination, but vaccines and other preventive strategies may offer improved disease control.

Blood biomarkers of neuronal injury in paediatric cerebral malaria and severe malarial anaemia

Persistent neurodisability is a known complication in paediatric survivors of cerebral malaria and severe malarial anaemia. Tau, ubiquitin C-terminal hydrolase-L1, neurofilament-light chain, and glial fibrillary acidic protein have proven utility as biomarkers that predict adverse neurologic outcomes in adult and paediatric disorders. In paediatric severe malaria, elevated tau is associated with mortality and neurocognitive complications. We aimed to investigate whether a multi-analyte panel including ubiquitin C-terminal hydrolase-L1, neurofilament-light chain, and glial fibrillary acidic protein can serve as biomarkers of brain injury associated with mortality and neurodisability in cerebral malaria and severe malarial anaemia. In a prospective cohort study of Ugandan children, 18 months to 12 years of age with cerebral malaria (n = 182), severe malarial anaemia (n = 158), and asymptomatic community children (n = 118), we measured admission blood levels of ubiquitin C-terminal hydrolase-L1, neurofilament-light chain, and glial fibrillary acidic protein. We investigated differences in biomarker levels, associations with mortality, blood-brain barrier integrity, neurodeficits and cognitive Z-scores in survivors up to 24-month follow-up. Admission ubiquitin C-terminal hydrolase-L1 levels were elevated >95th percentile of community children in 71 and 51%, and neurofilament-light chain levels were elevated >95th percentile of community children in 40 and 37% of children with cerebral malaria and severe malarial anaemia, respectively. Glial fibrillary acidic protein was not elevated in disease groups compared with controls. In cerebral malaria, elevated neurofilament-light chain was observed in 16 children who died in hospital compared with 166 survivors (P = 0.01); elevations in ubiquitin C-terminal hydrolase-L1 levels were associated with degree of blood-brain barrier disruption (P = 0.01); and the % predictive value for neurodeficits over follow-up (discharge, 6-, 12-, and 24 months) increased for ubiquitin C-terminal hydrolase-L1 (60, 67, 72, and 83), but not neurofilament-light chain (65, 68, 60, and 67). In cerebral malaria, elevated ubiquitin C-terminal hydrolase-L1 was associated with worse memory scores in children <5 years at malaria episode who crossed to over 5 years old during follow-up cognitive testing [β -1.13 (95% confidence interval -2.05, -0.21), P = 0.02], and elevated neurofilament-light chain was associated with worse attention in children ≥5 years at malaria episode and cognitive testing [β -1.08 (95% confidence interval -2.05, -1.05), P = 0.03]. In severe malarial anaemia, elevated ubiquitin C-terminal hydrolase-L1 was associated with worse attention in children <5 years at malaria episode and cognitive testing [β -0.42 (95% confidence interval -0.76, -0.07), P = 0.02]. Ubiquitin C-terminal hydrolase-L1 and neurofilament-light chain levels are elevated in paediatric cerebral malaria and severe malarial anaemia. In cerebral malaria, elevated neurofilament-light chain is associated with mortality whereas elevated ubiquitin C-terminal hydrolase-L1 is associated with blood-brain barrier dysfunction and neurodeficits over follow-up. In cerebral malaria, both markers are associated with worse cognition, while in severe malarial anaemia, only ubiquitin C-terminal hydrolase-L1 is associated with worse cognition.

Implementation of the Revised National Malaria Control Guidelines: Compliance and Challenges in Public Health Facilities in a Southern Nigerian State

Background

There has been a concerted effort to reduce malaria burden and bring malaria related mortality to zero. The objectives of this survey were to assess the level of adherence to the current revised malaria control guidelines in the public health facilities in Cross River State of Nigeria and to identify the challenges as well as suggest ways for improvement in treatment outcomes.

Methods

This was a mixed observational and qualitative survey conducted in 32 public health facilities from 21st to 25th June 2022. Treatment records on malaria were assessed for adherence to the National guidelines. In-depth interviews were conducted with 36 key informants and 4 purposefully selected stakeholders to identify the successes and challenges. Quantitative data were summarized and presented in simple proportions and percentages while qualitative information was recorded, the transcripts thematically coded, analyzed and presented using NVivo 11 software.

Results

The survey revealed that vector control program was poorly implemented across the state. For case management, presumptive treatment was frequently practiced especially at secondary health facilities for uncomplicated malaria. More than 60% of uncomplicated malaria were being treated with parenteral artemether instead of oral artemisinin combination therapy (ACTs) as recommended. Severe malaria were not treated with Intravenous (IV) Artesunate as first line drug in about 40% of the secondary health facilities. Key successes were noted in malaria management in pregnancy. Major challenges identified include: stock out of commodities, shortage of clinical man power, and low trust in parasitological diagnosis.

Conclusion

The survey showed that adherence to the key recommendations in various categories of malaria control among health care providers in the public health facilities was below expectation. Malaria preventive treatment in pregnancy with SP fared better perhaps because of its inclusion in ANC packages.

The association of intraleucocytic malaria pigment and disease severity in Papua New Guinean children with severe P. falciparum malaria

BACKGROUND

Plasmodium falciparum pigment-containing leucocytes (PCLs) are associated with adverse clinical manifestations of severe malaria in African children. However, limited data exist on the association of PCLs in settings outside of Africa.

METHODS

Thin films on peripheral blood slides obtained from children ages 6 months-10 y with severe malaria were examined for PCLs. The intraleucocytic pigment data were correlated with clinical phenotypic data such as severe anaemia, metabolic acidosis and coma to determine the association of PCLs with clinical phenotypes of severe malaria and outcome.

RESULTS

Of the 169 children with severe P. falciparum malaria confirmed by microscopy, 76% (129/169) had PCLs. Compared with children without PCLs, the presence (adjusted odds ratio [AOR] 3.2 [95% confidence interval {CI} 1.5 to 6.9], p≤0.01) and quantity (AOR 1.0 [95% CI 1.0 to 1.1], p=0.04) of pigment-containing monocytes (PCMs) was significantly associated with severe anaemia, while the quantity of both PCMs (AOR 1.0 [95% CI 1.0 to 1.1], p≤0.01) and pigment-containing neutrophils (AOR 1.0 [95% CI 1.0 to 1.1], p=0.01) was significantly associated with metabolic acidosis. Plasma P. falciparum histidine-rich protein-2 level negatively correlated with the platelet count (r=-0.5, p≤0.01) in patients with PCLs and no PCLs.

CONCLUSIONS

In Papua New Guinean children with severe P. falciparum malaria, the presence and quantity of PCLs are predictors of disease severity, severe anaemia and metabolic acidosis.

Whole-genome surveillance identifies markers of Plasmodium falciparum drug resistance and novel genomic regions under selection in Mozambique

IMPORTANCE

Malaria is a devastating disease caused by Plasmodium parasites. The evolution of parasite drug resistance continues to hamper progress toward malaria elimination, and despite extensive efforts to control malaria, it remains a leading cause of death in Mozambique and other countries in the region. The development of successful vaccines and identification of molecular markers to track drug efficacy are essential for managing the disease burden. We present an analysis of the parasite genome in Mozambique, a country with one of the highest malaria burdens globally and limited available genomic data, revealing current selection pressure. We contribute additional evidence to limited prior studies supporting the effectiveness of SWGA in producing reliable genomic data from complex clinical samples. Our results provide the identity of genomic loci that may be associated with current antimalarial drug use, including artemisinin and lumefantrine, and reveal selection pressure predicted to compromise the efficacy of current vaccine candidates.

Natural immunity to malaria preferentially targets the endothelial protein C receptor-binding regions of PfEMP1s

Antibody responses to variant surface antigens (VSAs) produced by the malaria parasite Plasmodium falciparum may contribute to age-related natural immunity to severe malaria. One VSA family, P. falciparum erythrocyte membrane protein-1 (PfEMP1), includes a subset of proteins that binds endothelial protein C receptor (EPCR) in human hosts and potentially disrupts the regulation of inflammatory responses, which may lead to the development of severe malaria. We probed peptide microarrays containing segments spanning five PfEMP1 EPCR-binding domain variants with sera from 10 Malian adults and 10 children to determine the differences between adult and pediatric immune responses. We defined serorecognized peptides and amino acid residues as those that elicited a significantly higher antibody response than malaria-naïve controls. We aimed to identify regions consistently serorecognized among adults but not among children across PfEMP1 variants, potentially indicating regions that drive the development of immunity to severe malaria. Adult sera consistently demonstrated broader and more intense serologic responses to constitutive PfEMP1 peptides than pediatric sera, including peptides in EPCR-binding domains. Both adults and children serorecognized a significantly higher proportion of EPCR-binding peptides than peptides that do not directly participate in receptor binding, indicating a preferential development of serologic responses at functional residues. Over the course of a single malaria transmission season, pediatric serological responses increased between the start and the peak of the season, but waned as the transmission season ended. IMPORTANCE Severe malaria and death related to malaria disproportionately affect sub-Saharan children under 5 years of age, commonly manifesting as cerebral malaria and/or severe malarial anemia. In contrast, adults in malaria-endemic regions tend to experience asymptomatic or mild disease. Our findings indicate that natural immunity to malaria targets specific regions within the EPCR-binding domain, particularly peptides containing EPCR-binding residues. Epitopes containing these residues may be promising targets for vaccines or therapeutics directed against severe malaria. Our approach provides insight into the development of natural immunity to a binding target linked to severe malaria by characterizing an "adult-like" response as recognizing a proportion of epitopes within the PfEMP1 protein, particularly regions that mediate EPCR binding. This "adult-like" response likely requires multiple years of malaria exposure, as increases in pediatric serologic response over a single malaria transmission season do not appear significant.

Antibody to Plasmodium falciparum Variant Surface Antigens, var Gene Transcription, and ABO Blood Group in Children With Severe or Uncomplicated Malaria

BACKGROUND

Antibodies to variant surface antigens (VSAs) such as Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) may vary with malaria severity. The influence of ABO blood group on antibody development is not understood.

METHODS

Immunoglobulin G antibodies to VSAs in Papua New Guinean children with severe (n = 41) or uncomplicated (n = 30) malaria were measured by flow cytometry using homologous P falciparum isolates. Isolates were incubated with ABO-matched homologous and heterologous acute and convalescent plasma. RNA was used to assess var gene transcription.

RESULTS

Antibodies to homologous, but not heterologous, isolates were boosted in convalescence. The relationship between antibody and severity varied by blood group. Antibodies to VSAs were similar in severe and uncomplicated malaria at presentation, higher in severe than uncomplicated malaria in convalescence, and higher in children with blood group O than other children. Six var gene transcripts best distinguished severe from uncomplicated malaria, including UpsA and 2 CIDRα1 domains.

CONCLUSIONS

ABO blood group may influence antibody acquisition to VSAs and susceptibility to severe malaria. Children in Papua New Guinea showed little evidence of acquisition of cross-reactive antibodies following malaria. Var gene transcripts in Papua New Guinean children with severe malaria were similar to those reported from Africa.

Trends in clinical features and severity of Plasmodium vivax malaria among children at tertiary care center in North India

BACKGROUND

Malaria is a significant cause of morbidity and mortality in adults and children. Plasmodium falciparum is the primary cause of severe malaria, but recently Plasmodium vivax is also recognized to cause severe malaria-associated morbidity and mortality. The study focuses on determining the mortality related to severity parameters in individuals under 12 years and their critical presentation in P.vivax malaria-infected children.

METHODS

A prospective cross-sectional hospital-based study was conducted at Safdarjung Hospital, New Delhi, and ICMR-NIMR, New Delhi. All clinically suspected cases were admitted for screening. Exclusion criteria (rapid malaria antigen test, microscopy and medication history) were applied to all the admitted patients (n = 221) to obtain P.vivax patients only. Patients aged ≤ 12 years were included in the study. DNA was extracted from dried blood spots and amplified by nested PCR, followed by visualization on gel electrophoresis.

RESULT

A total of 221 clinically suspected cases of malaria were screened for P.vivax. After implementing various exclusion criteria, 45/221 cases were enrolled for the study, among which 44.4% (20/45) of children had the symptoms of severe malaria in terms of cerebral malaria, thrombocytopenia, anemia, pancytopenia, acute respiratory distress syndrome and hemophagocytic lymphohistiocytosis.

CONCLUSION

Plasmodium vivax mono-infection can cause severe manifestation and must be treated as P.falciparum without any delay because it may lead to increased morbidity and mortality. A changing trend in clinical symptoms has shown in P.vivax which was an earlier phenomenon of P.falciparum.

Severe Falciparum and Vivax Malaria on the Thailand-Myanmar Border: A Review of 1503 Cases

BACKGROUND

The northwestern border of Thailand is an area of low seasonal malaria transmission. Until recent successful malaria elimination activities, malaria was a major cause of disease and death. Historically the incidences of symptomatic Plasmodium falciparum and Plasmodium vivax malaria were approximately similar.

METHODS

All malaria cases managed in the Shoklo Malaria Research Unit along the Thailand-Myanmar border between 2000 and 2016 were reviewed.

RESULTS

There were 80 841 consultations for symptomatic P. vivax and 94 467 for symptomatic P. falciparum malaria. Overall, 4844 (5.1%) patients with P. falciparum malaria were admitted to field hospitals, of whom 66 died, compared with 278 (0.34%) with P. vivax malaria, of whom 4 died (3 had diagnoses of sepsis, so the contribution of malaria to their fatal outcomes is uncertain). Applying the 2015 World Health Organization severe malaria criteria, 68 of 80 841 P. vivax admissions (0.08%) and 1482 of 94 467 P. falciparum admissions (1.6%) were classified as severe. Overall, patients with P. falciparum malaria were 15 (95% confidence interval, 13.2-16.8) times more likely than those with P. vivax malaria to require hospital admission, 19 (14.6-23.8) times more likely to develop severe malaria, and ≥14 (5.1-38.7) times more likely to die.

CONCLUSIONS

In this area, both P. falciparum and P. vivax infections were important causes of hospitalization, but life-threatening P. vivax illness was rare.

Renin as a Biomarker of Acute Kidney Injury and Mortality in Children With Severe Malaria or Sickle Cell Disease

BACKGROUND

Globally, a very high percentage of acute kidney injury (AKI) occurs in low- and middle-income countries (LMICs) where late recognition contributes to increased mortality. There are challenges with using existing biomarkers of AKI in LMICs. Emerging evidence suggests renin may serve as a biomarker of kidney injury that can overcome limitations in creatinine-based diagnostics.

METHODS

Two study populations in Uganda were assessed. Cohort #1 was a two-site, prospective cohort study enrolling 600 children with severe malaria (SM). Cohort #2 was a prospective cohort study enrolling 185 children with sickle cell disease (SCD) hospitalized with a vaso-occlusive crisis. Plasma or serum renin concentrations were measured in both cohorts of children at the time of hospital admission using Luminex® (Luminex Corporation, Austin, Texas, United States) or enzyme-linked immunosorbent assay (ELISA), respectively. We assessed the ability of renin to discriminate between children with or without AKI and between children who survived and children who died using receiver operating characteristic curves.

RESULTS

In both cohorts, renin concentrations were strongly associated with AKI and mortality. Renin was able to discriminate between children with or without AKI with an area under the curve (AUC) of 0.70 (95%CI, 0.65-0.74) in children with SM and 0.72 (95%CI, 0.6co3-0.81) in children with SCD. Renin was able to discriminate between children who survived and children who died with an AUC of 0.73 (95%CI, 0.63-0.83) in children with SM and 0.94 (95%CI, 0.89-0.99) in children with SCD. In Cohort #2, we compared renin against urine neutrophil gelatinase-associated lipocalin (NGAL) as the leading biomarker of AKI, and it had comparable performance in discriminating AKI and predicting mortality.

CONCLUSIONS

In two independent populations of children at risk of AKI with key differences in the etiology of kidney injury, renin was strongly associated with AKI and mortality and had moderate to good diagnostic performance to predict mortality.

Respiratory Distress Complicating Falciparum Malaria Imported to Berlin, Germany: Incidence, Burden, and Risk Factors

While European healthcare systems face resource shortages as a consequence of the coronavirus pandemic, numbers of imported falciparum malaria cases increased again with re-intensifying international travel. The aim of the study was to identify malaria-specific complications associated with a prolonged intensive care unit (ICU) length of stay (ICU-LOS) in the pre-COVID-19 era and to determine targets for their prevention. This retrospective observational investigation included all the cases treated from 2001 to 2015 at the Charité University Hospital, Berlin. The association of malaria-specific complications with the ICU-LOS was assessed using a multivariate Cox proportional hazard regression. The risk factors for the individual complications were determined using a multivariate Bayesian logistic regression. Among the 536 included cases, 68 (12.7%) required intensive care and 55 (10.3%) suffered from severe malaria (SM). The median ICU-LOS was 61 h (IQR 38-91 h). Respiratory distress, which occurred in 11 individuals (2.1% of the total cases, 16.2% of the ICU patients, and 20% of the SM cases), was the only complication independently associated with ICU-LOS (adjusted hazard ratio for ICU discharge by 61 h 0.24, 95% confidence interval, 95%CI, 0.08-0.75). Shock (adjusted odds ratio, aOR, 11.5; 95%CI, 1.5-113.3), co-infections (aOR 7.5, 95%CI 1.2-62.8), and each mL/kg/h fluid intake in the first 24 treatment hours (aOR 2.2, 95%CI 1.1-5.1) were the independent risk factors for its development. Respiratory distress is not rare in severe imported falciparum malaria, and it is associated with a substantial burden. Cautious fluid management, including in shocked individuals, and the control of co-infections may help prevent its development and thereby reduce the ICU-LOS.

Artemisinin-based combination therapy successfully treated two hyperparasitaemic Plasmodium falciparum cases

Hyperparasitaemia is an important event in the cascade of Plasmodium falciparum severe malaria (SM), and may also lead to SM associated complications and death, if left untreated. Here, we report two hyperparasitaemic patients with no life-threatening complications. Malaria diagnosis was performed using thick and thin blood smears and immunochromatographic-based rapid diagnostic tests (RDTs) purchased from three different manufacturers. Parasitaemia was calculated following the World Health Organization (WHO) guidelines. Haematological and biochemical investigations were also performed. Weekly follow-up of blood smear examination, blood pressure and temperature were recorded up to day 63. The first patient had 42% parasitaemia (100% asexual parasites). The second patient had 9.5% parasitaemia, comprising 46% asexual and 54% sexual stages, with a 1:1 male to female ratio. On the day of admission, both had presented abnormal haematological and biochemical parameters compared to the reference values. Remarkably, both the patients recovered successfully with oral artemisinin-based combination therapy (ACT) and a single dose of primaquine on day 1. Weekly follow-up did not show any parasite suggesting successful treatment with ACT without any side effects. The presence of hypergametocytaemia may hinder malaria elimination efforts, if not treated immediately.

Magnitude and patterns of severe Plasmodium vivax monoinfection in Vietnam: a 4-year single-center retrospective study

Introduction

Infection with Plasmodium vivax is a recognized cause of severe malaria including deaths. The exact burden and patterns of severe P. vivax monoinfections is however still not well quantified, especially in P. vivax endemic regions. We examined the magnitude and patterns of severe malaria caused by monoinfections of P. vivax and associated predictors among patients admitted to a tertiary care center for malaria in Vietnam.

Methods

A retrospective cohort study was conducted based on the patients' medical records at the Hospital for Tropical Diseases from January 2015 to December 2018. Extracted information included demographic, epidemiologic, clinical, laboratory and treatment characteristics.

Results

Monoinfections with P. vivax were found in 153 (34.5, 95% CI 30.3-39.1%) patients of whom, uncomplicated and severe malaria were documented in 89.5% (137/153, 95% CI 83.7-93.5%) and 10.5% (16/153, 95% CI 6.5-16.3%), respectively. Patterns of severe malaria included jaundice (8 cases), hypoglycemia (3 cases), shock (2 cases), anemia (2 cases), and cerebral malaria (1 case). Among 153 patients, 73 (47.7%) had classic malaria paroxysm, 57 (37.3%) had >7 days of illness at the time of admission, and 40 (26.1%) were referred from other hospitals. A misdiagnosis as having other diseases from malaria cases coming from other hospitals was up to 32.5% (13/40). Being admitted to hospital after day 7th of illness (AOR = 6.33, 95% CI 1.14-35.30, p = 0.035) was a predictor of severe malaria. Severe malaria was statistically associated with longer hospital length of stay (p = 0.035). Early and late treatment failures and recrudescence were not recorded. All patients recovered completely.

Discussion

This study confirms the emergence of severe vivax malaria in Vietnam which is associated with delayed hospital admission and increased hospital length of stay. Clinical manifestations of P. vivax infection can be misdiagnosed which results in delayed treatment. To meet the goal of malaria elimination by 2030, it is crucial that the non-tertiary hospitals have the capacity to quickly and correctly diagnose malaria and then provide treatment for malaria including P. vivax infections. More robust studies need to be conducted to fully elucidate the magnitude of severe P. vivax in Vietnam.

A Water-Soluble Polymer-Lumefantrine Conjugate for the Intravenous Treatment of Severe Malaria

Uncomplicated malaria is effectively treated with oral artemisinin-based combination therapy (ACT). Yet, there is an unmet clinical need for the intravenous treatment of the more fatal severe malaria. There is no combination intravenous therapy for uncomplicated due to the nonavailability of a water-soluble partner drug for the artemisinin, artesunate. The currently available treatment is a two-part regimen split into an intravenous artesunate followed by the conventional oral ACT . In a novel application of polymer therapeutics, the aqueous insoluble antimalarial lumefantrine is conjugated to a carrier polymer to create a new water-soluble chemical entity suitable for intravenous administration in a clinically relevant formulation . The conjugate is characterized by spectroscopic and analytical techniques, and the aqueous solubility of lumefantrine is determined to have increased by three orders of magnitude. Pharmacokinetic studies in mice indicate that there is a significant plasma release of lumefantrine and production its metabolite desbutyl-lumefantrine (area under the curve of metabolite is ≈10% that of the parent). In a Plasmodium falciparum malaria mouse model, parasitemia clearance is 50% higher than that of reference unconjugated lumefantrine. The polymer-lumefantrine shows potential for entering the clinic to meet the need for a one-course combination treatment for severe malaria.

The kidney-brain pathogenic axis in severe falciparum malaria

Severe falciparum malaria is a medical emergency and a leading cause of death and neurodisability in endemic areas. Common complications include acute kidney injury (AKI) and cerebral malaria, and recent studies have suggested links between kidney and brain dysfunction in Plasmodium falciparum infection. Here, we review these new findings and present the hypothesis of a pivotal pathogenic crosstalk between the kidneys and the brain in severe falciparum malaria. We highlight the evidence of a role for distant organ involvement in the development of cerebral malaria and subsequent neurocognitive impairment post-recovery, describe the challenges associated with current diagnostic shortcomings for both AKI and brain involvement in severe falciparum malaria, and explore novel potential therapeutic strategies.

Food and Drug Administration Approval of Artesunate for Severe Malaria: Enough to Achieve Best Practice?

Intravenous artesunate has been the global standard of care for severe malaria for over 2 decades. Yet, until recently, artesunate has only been available to patients through an expanded-access protocol from the Centers for Disease Control and Prevention. In May 2020, the Food and Drug Administration approved artesunate, allowing US hospitals to stock the drug and ensuring prompt treatment for this life-threatening infection. However, because of artesunate's high cost and the infrequency of severe malaria in the United States, hospitals may be reluctant to stock the drug. As US health systems weigh the decision to stock artesunate, we propose a hospital tier framework to inform this decision and support clinicians caring for patients who present with severe malaria.

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.

Post-artesunate Delayed Hemolysis in Patients With Severe Malaria in the United States-April 2019 Through July 2021

BACKGROUND

Studies have demonstrated the safety and efficacy of intravenous artesunate (IVAS) for treatment of severe malaria in endemic and nonendemic countries. However, post-artesunate delayed hemolysis (PADH) is an increasingly recognized phenomenon after its administration. This study describes the prevalence and outcomes of PADH events among severe malaria cases treated with IVAS in the United States.

METHODS

Patients diagnosed with severe malaria and treated with IVAS from April 2019 to July 2021 were included. Demographic, clinical, laboratory, therapeutic, and outcome measures were described using proportions, medians, and interquartile range. Patients reported to experience PADH were compared with those not reported to have PADH, and tests of significance were performed.

RESULTS

Of 332 patients included in our analysis, 9 (2.7%) experienced PADH. The majority of infections in both groups were in non-Hispanic Black individuals. Parasite density (11.0% vs 8.0%), admission hemoglobin (11.0 g/dL vs 11.8 g/dL) were similar in the 2 groups. Total bilirubin levels at admission (4.7 mg/dL vs 2.2 mg/dL) and within 8 hours after completion of IVAS (2.6 mg/dL vs 1.2 mg/dL) were notably higher in PADH patients. Cumulative IVAS dose of >9.5 mg/kg and >3 doses of IVAS were risk factors for PADH. The majority (7 of 9) of PADH cases were diagnosed within 2 weeks after initiation of IVAS. Five patients (56%) required blood transfusions, and all recovered without sequelae.

CONCLUSIONS

PADH is an uncommon and self-limiting adverse event in many cases; weekly monitoring of hemoglobin and hemolytic markers may identify cases requiring intervention in a timely manner.

High Plasma Levels of Neopterin Are Associated with Increased Mortality among Children with Severe Malaria in Benin

Among the barriers to accessing adequate treatment and high-level monitoring for malaria febrile patients is the lack of effective prognostic markers. Neopterin, which is a marker of monocyte/macrophage activation, was found have increased during severe malaria. In this study, we used quantitative ELISA in order to assess the levels of plasma soluble neopterin in 151 patients from a cohort of Beninese children with severe malaria. We evaluated the prognostic accuracy of this molecule in order to predict the outcome of the disease. Our results show that neopterin levels were not significantly different between patients with different forms of severe malaria, including severe non-cerebral malaria (SNCM) and cerebral malaria (CM). However, the levels of this molecule were found to be higher in patients with severe malarial anemia (SMA) among both CM and SNCM cases (p-value = 0.02). Additionally, the levels of this molecule were found to be higher in patients who died from these pathologies compared to those who survived among the two clinical groups (p-value < 0.0001) and within the same group (p-value < 0.0001 for the CM group, p-value = 0.0046 for the SNCM group). The AUC-ROC for fatality among all the severe cases was 0.77 with a 95%CI of (0.69-0.85). These results suggest that plasma neopterin levels constitute a potential biomarker for predicting fatality among severe falciparum malaria patients.

A severe case of Plasmodium falciparum malaria imported by a French traveler from Cameroon to French Guiana despite regular intake of Artemisia annua herbal tea

The use of herbal tea with Artemisia annua by travelers and traditional communities in Africa has increased in recent years as a supposed form of malaria prophylaxis, although its use is not recommended due to lack of efficacy. The risk of severe malaria complications that can lead to death is real regarding said behavior, and awareness needs to be raised. We report a case of severe Plasmodium falciparum malaria imported in the Amazon rainforest by a traveler returning from Cameroon who treated himself with Artemisia annua herbal tea.

Relation between Increased IL-10 Levels and Malaria Severity: A Systematic Review and Meta-Analysis

The roles of anti-inflammatory cytokines in the pathogenesis of severe malaria have been widely studied, and the role of IL-10 in the pathogenesis of severe malaria remains unclear. Therefore, we performed a systematic review and meta-analysis to determine the difference in IL-10 levels between patients with severe malaria and those with non-severe malaria. The search for relevant studies was performed using PubMed, Scopus, and Embase from 1 February 2022 to 12 February 2022. The quality of the included studies was assessed according to the guidelines of the Strengthening the Reporting of Observational Studies in Epidemiology. The random-effects model was used to estimate the pooled effect. In all, 1215 studies were identified, and 19 were included in the quantitative syntheses. The results showed that patients with severe malaria had a higher IL-10 level than those with non-severe malaria (p = 0.03, pooled standardized mean difference: 0.74, 95% CI: 0.08-1.40, I²: 97.22%, 19 studies/21 sub studies). The meta-analysis results demonstrated increased IL-10 levels in patients with severe malaria compared with those with non-severe malaria. However, with the heterogeneity of the meta-analysis results, further studies are required to confirm the changes in the IL-10 levels according to the severity of malaria and to investigate whether a combination of other severity parameters with IL-10 levels could be an alternative marker for severe malaria.

Cross-sectional prevalence and pattern of non-anaemia severe malaria among 2-10 year olds in Sokoto in Northwestern Nigeria

Malaria is highly prevalent in Nigeria and accounts for approximately 40% of global malaria mortality. However, most reports on severe malaria in Nigeria are from hospital-based studies without accurate information from communities; thus, malaria-related deaths in the community are left untracked. This study aimed to describe the prevalence and pattern of severe malaria in a community in Northwestern Nigeria. A cross-sectional study was conducted among 2-10-year-old children in Sokoto, in August and December 2016, to determine the endemicity of malaria based on Plasmodium falciparum prevalence rate (PfPR2-10) and to describe the disease pattern. Severe malaria was diagnosed according to the World Health Organisation criteria. Data were described using Stata version 15. The prevalence of non-anaemia severe malaria was higher than expected (2.6%), considering the endemicity pattern which was mesoendemic based on a PfPR2-10 of 34.8%. The mean age of children with severe malaria was 3.73 years, and the male-female ratio was 2:1. However, 54.0% of the patients had hyperparasitaemia. A relatively high prevalence of non-anaemia severe malaria was found in Wamakko. This finding suggests the need to identify and treat cases in the community using modifications of current strategies, particularly seasonal malaria chemoprophylaxis.

Whole Blood Transfusion for Severe Malarial Anemia in a High Plasmodium falciparum Transmission Setting

BACKGROUND

Severe malaria resulting from Plasmodium falciparum infection is the leading parasitic cause of death in children worldwide, and severe malarial anemia (SMA) is the most common clinical presentation. The evidence in support of current blood transfusion guidelines for patients with SMA is limited.

METHODS

We conducted a retrospective cohort study of 911 hospitalized children with SMA in a holoendemic region of Zambia to examine the association of whole blood transfusion with in-hospital survival. Data were analyzed in adjusted logistic regression models using multiple imputation for missing data.

RESULTS

The median age of patients was 24 months (interquartile range, 16-30) and overall case fatality was 16%. Blood transfusion was associated with 35% reduced odds of death in children with SMA (odds ratio, 0.65; 95% confidence interval, .52-.81; P = .0002) corresponding to a number-needed-to-treat (NNT) of 14 patients. Children with SMA complicated by thrombocytopenia were more likely to benefit from transfusion than those without thrombocytopenia (NNT = 5). Longer storage time of whole blood was negatively associated with survival and with the posttransfusion rise in the platelet count but was not associated with the posttransfusion change in hemoglobin concentration.

CONCLUSIONS

Whole blood given to pediatric patients with SMA was associated with improved survival, mainly among those with thrombocytopenia who received whole blood stored for <4 weeks. These findings point to a potential use for incorporating thrombocytopenia into clinical decision making and management of severe malaria, which can be further assessed in prospective studies, and underline the importance of maintaining reliable blood donation networks in areas of high malaria transmission.

Intestinal Injury Biomarkers Predict Mortality in Pediatric Severe Malaria

Severe malaria (SM) increases the risk of invasive bacterial infection, and there is evidence to suggest increased gastrointestinal permeability. Studies have shown sequestration of infected erythrocytes in intestinal microvasculature, and in vivo studies of rectal mucosa have demonstrated disruption of microvascular blood flow. However, the extent of intestinal injury in pediatric malaria is not well characterized. In this study, two serum biomarkers of intestinal injury, trefoil factor 3 (TFF3) and intestinal fatty acid binding protein (I-FABP), were analyzed in 598 children with SM and 120 healthy community children (CC), 6 months to 4 years of age. Serum was collected at enrollment and 1 month for laboratory studies, and participants were monitored for 12 months. Intestinal injury biomarkers were significantly elevated in children with SM, with 18.1% having levels of TFF3 and/or I-FABP greater than the 99th percentile of CC levels. TFF3 levels continued to be elevated at 1 month, while I-FABP levels were comparable to CC levels. Both markers predicted in-hospital mortality {odds ratio (OR) (95% confidence interval [CI]), 4.4 (2.7, 7.3) and 2.3 (1.7, 3.1)} for a natural log increase in TFF3 and I-FABP, respectively. TFF3 was also associated with postdischarge mortality (OR, 2.43 [95% CI, 1.1, 4.8]). Intestinal injury was associated with acute kidney injury (AKI), acidosis (P < 0.001 for both), and angiopoietin 2, a maker of endothelial activation. In conclusion, intestinal injury is common in pediatric severe malaria and is associated with an increased mortality. It is strongly associated with AKI, acidosis, and endothelial activation. IMPORTANCE In children with severe malaria, intestinal injury is a common complication associated with increased mortality. Intestinal injury is associated with acute kidney injury, acidosis, and endothelial activation. Interventions promoting intestinal regeneration and repair represent novel approaches to improve outcomes.

Transforming Growth Factor-β Concerning Malarial Infection and Severity: A Systematic Review and Meta-Analysis

Transforming growth factor-β (TGF-β) is important in the pathophysiology of malaria, but its role in acute and severe malaria is largely unknown. As a result, this study used a meta-analysis approach to investigate the difference in TGF-β levels between several groups of malaria patients and healthy controls. The systematic review protocol was registered at PROSPERO (ID: CRD42022318864). From inception to 7 March 2022, studies that reported TGF-β levels in patients with uncomplicated and healthy controls and patients with severe and uncomplicated malaria were searched in PubMed, Scopus and Embase. The assessment of the quality of the included studies was conducted according to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines. Qualitative and quantitative syntheses were performed to narratively describe and quantitatively pool the mean difference (MD) in TGF-β levels between uncomplicated malaria and healthy controls, and between severe and uncomplicated malaria, using a random-effects model. A total of 1027 relevant articles were identified, and 13 studies were included for syntheses. The meta-analysis results show 233 patients with uncomplicated malaria and 239 healthy controls. Patients with uncomplicated malaria (233 cases) had lower mean TGF-β levels than healthy controls (239 cases; p < 0.01, pooled MD = −14.72 pg/mL, 95% confidence interval (95% CI) = −20.46 to 8.99 pg/mL, I2 = 98.82%, seven studies). The meta-analysis found no difference in mean TGF-β levels between patients with severe malaria (367 cases) and patients with uncomplicated malaria (180 cases; p = 0.11, pooled MD = −6.07 pg/mL, 95% CI = −13.48 to 1.35 pg/mL, I2 = 97.73%, six studies). The meta-analysis demonstrated decreased TGF-β levels in patients with uncomplicated malaria compared to healthy controls. In addition, no difference in TGF-β levels was found between patients with severe and uncomplicated malaria. More research is needed to determine whether TGF-β levels could be a candidate marker for malarial infection or disease severity.

Comparative Analysis of Host Metabolic Alterations in Murine Malaria Models with Uncomplicated or Severe Malaria

Malaria varies in severity, with complications ranging from uncomplicated to severe malaria. Severe malaria could be attributed to peripheral hyperparasitemia or cerebral malaria. The metabolic interactions between the host and Plasmodium species are yet to be understood during these infections of varied pathology and severity. An untargeted metabolomics approach utilizing the liquid chromatography-mass spectrometry platform has been used to identify the affected host metabolic pathways and associated metabolites in the serum of murine malaria models with uncomplicated malaria, hyperparasitemia, and experimental cerebral malaria. We report that mice with malaria share similar metabolic attributes like higher levels of bile acids, bile pigments, and steroid hormones that have been reported for human malaria infections. Moreover, in severe malaria, upregulated levels of metabolites like phenylalanine, histidine, valine, pipecolate, ornithine, and pantothenate, with decreased levels of arginine and hippurate, were observed. Metabolites of sphingolipid metabolism were upregulated in experimental cerebral malaria. Higher levels of 20-hydroxy-leukotriene B₄ and epoxyoctadecamonoenoic acids were found in uncomplicated malaria, with lower levels observed for experimental cerebral malaria. Our study provides insights into host biology during different pathological stages of malaria disease and would be useful for the selection of animal models for evaluating diagnostic and therapeutic interventions against malaria. The raw data files are available via MetaboLights with the identifier MTBLS4387.

Procalcitonin as a Candidate Biomarker for Malarial Infection and Severe Malaria: A Meta-Analysis

Procalcitonin (PCT), as a marker of malaria severity, remains to be investigated. The present study collated and compared the levels of PCT between patients with severe malaria, uncomplicated malaria, and control participants to assess their role in predicting malaria infection and disease severity. The systematic review was registered at PROSPERO with registration number CRD42021297243. The search for relevant studies that reported PCT in patients with malaria was performed in PubMed, Scopus, and Web of Science. The following meta-analyses were conducted; (1) the pooled mean PCT levels in patients with severe and uncomplicated malaria, and (2) the pooled mean difference in PCT levels between patients with severe and uncomplicated malaria. Fifteen studies were included for qualitative and quantitative syntheses. The meta-analysis results show that the pooled mean PCT levels in patients with uncomplicated malaria were 3.92 ng/mL (95% CI: 2.26-5.58 ng/mL, I²: 96.5, five studies), whereas the pooled mean PCT levels in patients with severe malaria were 14.13 ng/mL (95% CI: 8.75-19.5 ng/mL, I²: 92.6, six studies). The meta-analysis showed that patients with severe malaria had an equal mean of PCT compared to those with uncomplicated malaria when the random-effects model was used (p: 0.055, weighted mean difference: 6.93, 95% CI: -0.16-14.02, I²: 84.6%, four studies). There were probable correlations between the level of parasitemia, immunity level, and possibly bacterial or other parasitic co-infection that could affect the PCT level among different clinical severities of malaria. Therefore, the PCT level alone does not seem to be a suitable biomarker to discriminate the severe/uncomplicated or infected/uninfected cases. Further studies should investigate the increased PCT levels in combination with other markers in association with malaria infection and severity.

Outcomes reported in trials of treatments for severe malaria: The need for a core outcome set

OBJECTIVES

Malaria is one of the most important parasitic infectious diseases worldwide. Despite the scale-up of effective antimalarials, mortality rates from severe malaria (SM) remain significantly high; thus, numerous trials are investigating both antimalarials and adjunctive therapy. This review aimed to summarise all the outcome measures used in trials in the last 10 years to see the need for a core outcome set.

METHODS

A systematic review was undertaken to summarise outcomes of individually randomised trials assessing treatments for SM in adults and children. We searched key databases and trial registries between 1 January 2010 and 30 July 2020. Non-randomised trials were excluded to allow comparison of similar trials. Trial characteristics including phase, region, population, interventions, were summarised. All primary and secondary outcomes were extracted and categorised using a taxonomy table.

RESULTS

Twenty-seven of 282 screened trials met our inclusion criteria, including 10,342 patients from 19 countries: 19 (70%) trials from Africa and 8 (30%) from Asia. A large amount of heterogeneity was observed in the selection of outcomes and instruments, with 101 different outcomes measures recorded, 78/101 reported only in a single trial. Parasitological outcomes (17 studies), neurological status (14 studies), death (14 studies) and temperature (10 studies), were the most reported outcomes. Where an outcome was reported in >1 study it was often measured differently: temperature (4 different measures), renal function (7 measures), nervous system (13 measures) and parasitology (10 measures).

CONCLUSION

Outcomes used in SM trials are inconsistent and heterogeneous. Absence of consensus for outcome measures used impedes research synthesis and comparability of different interventions. This systematic review demonstrates the need to develop a standardised collection of core outcomes for clinical trials of treatments for SM and next steps to include the development of a panel of experts in the field, a Delphi process, and a consensus meeting.

Treatment outcome and factors associated with mortality due to malaria in Munini District Hospital, Rwanda in 2016-2017: Retrospective cross-sectional study

Introduction

Malaria is a major public health burden in developing countries despite efforts made by several countries. This disease leads to high morbidity and mortality among Rwandans, particularly in the Southern Province where it was the sixth national cause of morality; at Munini hospital it is the first cause of mortality, but the associated factors remain unknown. In this study, we determined the factors associated with deaths among patients with severe malaria to come up with evidence-based interventions to prevent malaria and its factors.

Methods

A retrospective cross-sectional study was conducted on malaria patients who were treated at the Munini District Hospital from 2016 to 2017. Data were collected from the hospital records or registers relating to patients who were admitted with severe malaria. The odds ratio was estimated by bivariate logistic regression and multivariate hierarchical regression models for determining the associated factors of deaths. Data were analyzed using STATA/MP Version 14.1 and Epi-info with proportions.

Results

The study population were mostly women (n = 237, 59.1%), farmers (n = 313, 78.05%), aged 16-30 years (n = 107, 26.68%). Our results indicated that the majority of deaths were women (56.25%). Socio-economic and clinical determinants are important predictors of death among patients with severe malaria. Patients with coma had higher odds of dying (AOR = 7.31, 95% CI :3.33-16.1, p < 0.001) than those who were not. The possibility of mortality increased by almost four times in patients who delayed consultation by a day (AOR = 3.7, 95%CI:1.8-4.1; p < 0.001) compared to those who came in very early. Patients who had severe malaria in the dry season were at a lower risk of mortality (AOR = 0.23, 95%CI:0.08-0.64, p = 0.005) compared to those with severe malaria during the rainy season.

Conclusion

Lack of health insurance, age of the patient, delayed diagnosis, coma, proximity and access to healthcare services, and weather conditions were the major factors associated with mortality among patients with severe malaria. Comprehensive, long-term, equity-based healthcare interventions and immediate care strategies are recommended.

Caregivers' perception and determinants of delayed presentation of children with severe malaria in an emergency room in Benin City, Nigeria

INTRODUCTION

Severe malaria is a leading cause of mortality due to late presentation to health facilities. Hence, there is a need to identify and mitigate factors promoting delayed presentation with severe malaria.

OBJECTIVE

This study aimed to evaluate determinants of delayed presentation of children with severe malaria in a tertiary referral hospital.

METHODS

This study adopted a descriptive, cross-sectional design. The participants were children with a diagnosis of severe malaria, based on WHO diagnostic criteria. Delayed presentation was defined as presentation at the referral centre at >3 days of illness. Inferential analyses were done to identify factors associated with delayed presentation. P < 0.05 was considered statistically significant.

RESULTS

A total of 126 children with severe malaria participated in the study; their mean (standard deviation) age was 4.2 (5.3) years. The prevalence of delayed presentation in this study is 37.3%. Socio-economic class (P = 0.003); marital status (P = 0.015) and the number of health facilities visited before admission in the referral centre (P = 0.008) were significantly associated with delayed presentation. Children from upper socio-economic class were thrice more likely to present late, compared to those from lower social class (odds ratio [OR] = 3.728, 95% confidence interval [CI]: 1.694-8.208; P = 0.001). Likewise, the Yorubas were more delayed than the Binis (OR = 0.408, 95% CI: 0.180-0.928; P = 0.033). There was a negative correlation between caregivers' perception of treatment (r = -0.113, P = 0.21) of convulsion in severe malaria and timing of presentation.

CONCLUSIONS

Delayed presentation is common with multifactorial determinants in the setting. Health education of caregivers on the consequences of delayed presentation in severe malaria is desirable.

Updates in central nervous system malaria: literature review and considerations

PURPOSE OF REVIEW

Cerebral malaria (CM) represents one of the most common and severe complications of Plasmodium falciparum infection, leading to high morbidity and mortality along with challenging sequelae, especially in children.

RECENT FINDINGS

Although CM pathogenesis remains unclear due to the few studies made and the difficulty to analyze affected patients, there are valid theories involving P. falciparum endothelium interactions, and clinical manifestations have been better investigated and differentiated between adults and children.

SUMMARY

At the time of writing, diagnostic management is based on fast severe malaria identification by blood smear (thin and thick). However, newer techniques involving molecular testing (such as PCR or LAMP) and biomarkers identification are now available. It is also important to check patients' cerebral functions. As regards therapeutic management, although we could rely on several options, artesunate represents the gold standard treatment. Cerebral complications such as seizures and coma need to be managed as well.

Identifying Targets of Protective Antibodies against Severe Malaria in Papua, Indonesia, Using Locally Expressed Domains of Plasmodium falciparum Erythrocyte Membrane Protein 1

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), a diverse family of multidomain proteins expressed on the surface of malaria-infected erythrocytes, is an important target of protective immunity against malaria. Our group recently studied transcription of the var genes encoding PfEMP1 in individuals from Papua, Indonesia, with severe or uncomplicated malaria. We cloned and expressed domains from 32 PfEMP1s, including 22 that were upregulated in severe malaria and 10 that were upregulated in uncomplicated malaria, using a wheat germ cell-free expression system. We used Luminex technology to measure IgG antibodies to these 32 domains and control proteins in 63 individuals (11 children). At presentation to hospital, levels of antibodies to PfEMP1 domains were either higher in uncomplicated malaria or were not significantly different between groups. Using principal component analysis, antibodies to 3 of 32 domains were highly discriminatory between groups. These included two domains upregulated in severe malaria, a DBLβ13 domain and a CIDRα1.6 domain (which has been previously implicated in severe malaria pathogenesis), and a DBLδ domain that was upregulated in uncomplicated malaria. Antibody to control non-PfEMP1 antigens did not differ with disease severity. Antibodies to PfEMP1 domains differ with malaria severity. Lack of antibodies to locally expressed PfEMP1 types, including both domains previously associated with severe malaria and newly identified targets, may in part explain malaria severity in Papuan adults.

Prevalence of Signs of Severity Identified in the Thai Population with Malaria: A Systematic Review and Meta-Analysis

Understanding the prevalence of signs of severity identified in the Thai population with malaria could aid clinical management and disease control efforts, decrease mortality, and promote malaria elimination in Thailand. This systematic review aimed to collate the evidence regarding signs of severity identified in the Thai population with malaria. MEDLINE, Web of Science, and Scopus were searched for potentially relevant studies. The quality of the included studies was assessed using the Joanna Briggs Institute critical appraisal tools. The pooled prevalence of signs of severity among patients with severe malaria and the pooled proportion of each sign of severity among all signs of severity were estimated using random-effects models. Heterogeneity among included studies was assessed using Cochran’s Q test. A subgroup analysis was performed to evaluate whether differences in pooled estimates between different study sites. Publication bias was assessed by visualizing funnel plot asymmetry and using Egger’s test. Among 741 studies identified by literature searching, 12 studies of a total of 2900 patients with severe malaria, in 7 Thai hospitals, met the eligibility criteria. Results of meta-analyses showed that the signs of the severity of malaria with the highest prevalence in Thailand were jaundice (54%), hyperparasitemia (47%), impaired consciousness/coma (21%), acidosis (18%), renal impairment (13%), shock (10%), convulsions (9%), severe anemia (8%), pulmonary edema/acute respiratory distress syndrome (ARDS) (8%), hypoglycemia (4%), and bleeding/disseminated intravascular coagulation (DIC) (2%). The signs of the severity of malaria that made up the highest proportion of all signs of severity identified in the Thai population with malaria were hyperparasitemia (33%), jaundice (33%), impaired consciousness/coma (12%), acidosis (9%), renal impairment (7%), severe anemia (6%), convulsions (5%), shock (5%), pulmonary edema/ARDS (3%), bleeding/DIC (1%), and hypoglycemia (1%). The present study revealed the prevalence of signs of severity identified in the Thai population with malaria. Jaundice, hyperparasitemia, and impaired consciousness/coma were the most common signs of severity identified. These results may inform the management of patients with severe malaria and promote malaria-elimination efforts in Thailand.

Safety and Effectiveness of Intravenous Artesunate for Treatment of Severe Malaria in the United States-April 2019 Through December 2020

BACKGROUND

Severe malaria can be deadly and requires treatment with intravenous artesunate (IVAS). The Centers for Disease Control and Prevention provided IVAS starting 1 April 2019 for all patients with severe malaria in the United States. This study describes the safety and effectiveness of IVAS in these patients.

METHODS

Patients meeting criteria for severe malaria April 2019-December 2020 who received IVAS were included. Demographic, clinical, laboratory, adverse event, and outcome information were collected. Clinical presentation, time to reach 1% and 0% parasitemia, adverse events, and death were described using proportions, medians, interquartile range (IQR), and tests of significance for differences in proportions.

RESULTS

Of 280 patients included, the majority were male (61.4%), Black (75.0%), with a median age of 35 years (IQR: 15.8-53.9). Most had Plasmodium falciparum (83.6%) with median parasitemia of 8.0% (IQR: 4.6-13.2). Of 170 patients with information, 159 (93.5%) reached ≤1% parasitemia by the third IVAS dose with a median time of 17.6 hours (IQR: 10.8-28.8), and 0% parasitemia in a median of 37.2 hours (IQR 27.2-55.2). Patients with parasite densities >10% and those requiring adjunct therapy had significantly higher parasite clearance times. Adverse events associated with IVAS were reported in 4.8% (n = 13 of 271). Eight patients had post-artesunate delayed hemolysis that resolved. There were 5 (1.8%) deaths, all attributable to severe malaria.

CONCLUSIONS

IVAS is a safe and effective drug for the treatment of severe malaria in the United States; timely administration can be lifesaving.

Insilico Functional Analysis of Genome-Wide Dataset From 17,000 Individuals Identifies Candidate Malaria Resistance Genes Enriched in Malaria Pathogenic Pathways

Recent genome-wide association studies (GWASs) of severe malaria have identified several association variants. However, much about the underlying biological functions are yet to be discovered. Here, we systematically predicted plausible candidate genes and pathways from functional analysis of severe malaria resistance GWAS summary statistics (N = 17,000) meta-analysed across 11 populations in malaria endemic regions. We applied positional mapping, expression quantitative trait locus (eQTL), chromatin interaction mapping, and gene-based association analyses to identify candidate severe malaria resistance genes. We further applied rare variant analysis to raw GWAS datasets (N = 11,000) of three malaria endemic populations including Kenya, Malawi, and Gambia and performed various population genetic structures of the identified genes in the three populations and global populations. We performed network and pathway analyses to investigate their shared biological functions. Our functional mapping analysis identified 57 genes located in the known malaria genomic loci, while our gene-based GWAS analysis identified additional 125 genes across the genome. The identified genes were significantly enriched in malaria pathogenic pathways including multiple overlapping pathways in erythrocyte-related functions, blood coagulations, ion channels, adhesion molecules, membrane signalling elements, and neuronal systems. Our population genetic analysis revealed that the minor allele frequencies (MAF) of the single nucleotide polymorphisms (SNPs) residing in the identified genes are generally higher in the three malaria endemic populations compared to global populations. Overall, our results suggest that severe malaria resistance trait is attributed to multiple genes, highlighting the possibility of harnessing new malaria therapeutics that can simultaneously target multiple malaria protective host molecular pathways.

Intravenous Artesunate for the Treatment of Severe Imported Malaria: Implementation, Efficacy, and Safety in 1391 Patients

BACKGROUND

Intravenous artesunate is the World Health Organization-recommended first-line treatment for severe malaria worldwide, but it is still not fully licensed in Europe. Observational studies documenting its safety and efficacy in imported malaria are thus essential.

METHODS

We prospectively collected clinical and epidemiological features of 1391 artesunate-treated patients among 110 participant centers during the first 7 years (2011-2017) of a national program implemented by the French Drug Agency.

RESULTS

Artesunate became the most frequent treatment for severe malaria in France, rising from 9.9% in 2011 to 71.4% in 2017. Mortality was estimated at 4.1%. Treatment failure was recorded in 27 patients, but mutations in the Kelch-13 gene were not observed. Main reported adverse events (AEs) were anemia (136 cases), cardiac events (24, including 20 episodes of conduction disorders and/or arrhythmia), and liver enzyme elevation (23). Mortality and AEs were similar in the general population and in people with human immunodeficiency virus, who were overweight, or were pregnant, but the only pregnant woman treated in the first trimester experimented a hemorrhagic miscarriage. The incidence of post-artesunate-delayed hemolysis (PADH) was 42.8% when specifically assessed in a 98-patient subgroup, but was not associated with fatal outcomes or sequelae. PADH was twice as frequent in patients of European compared with African origin.

CONCLUSIONS

Artesunate was rapidly deployed and displayed a robust clinical benefit in patients with severe imported malaria, despite a high frequency of mild to moderate PADH. Further explorations in the context of importation should assess outcomes during the first trimester of pregnancy and collect rare but potentially severe cardiac AEs.

Elevated admission C-reactive protein to albumin ratios are associated with disease severity and respiratory complications in adults with imported falciparum malaria

BACKGROUND

In imported falciparum malaria, systemic inflammation with increased capillary permeability can cause life-threatening complications, such as acute pulmonary edema (APO) or adult respiratory distress syndrome (ARDS). This observational study assessed the association of the admission serum albumin level (ALB) and C-reactive protein to albumin ratio (CRP/ALB) with disease severity and these respiratory complications.

METHODS

All adult cases hospitalized during 2001-2015 in the Charité University Hospital, Berlin, with ALB and CRP values measured upon admission, were retrospectively analysed.

RESULTS

Seventy-six patients were enrolled (26 female, median age: 37 y), 60 with uncomplicated malaria and 16 with severe malaria (SM). SM was associated with lower ALB (p<0.0001) and higher CRP/ALB (p<0.0001) values; the areas under the receiver operator curves (AUROCs) were 0.85 (95% CI 0.74 to 0.96) for ALB and 0.88 (95% CI 0.80 to 0.97) for CRP/ALB. Radiologic changes consistent with APO/ARDS were detectable in 5 of 45 admission chest X-rays performed (11.1%); the AUROCs were 0.86 (95% CI 0.74 to 0.99) for ALB and 0.91 (95% CI 0.82 to 0.99) for CRP/ALB.

CONCLUSIONS

Diminished admission ALB levels and elevated CRP/ALB ratios are associated with disease severity and respiratory complications in imported falciparum malaria. These readily and ubiquitously available markers may facilitate early identification of at-risk patients.

The Impact of Undernutrition on Cognition in Children with Severe Malaria and Community Children: A Prospective 2-Year Cohort Study

BACKGROUND

The frequency of recovery from undernutrition after an episode of severe malaria, and the relationship between undernutrition during severe malaria and clinical and cognitive outcomes are not well characterized.

METHODS

We evaluated undernutrition and cognition in children in Kampala, Uganda 18 months to 5 years of age with cerebral malaria (CM), severe malarial anemia (SMA) or community children (CC). The Mullen Scales of Early Learning was used to measure cognition. Undernutrition, defined as 2 SDs below median for weight-for-age (underweight), height-for-age (stunting) or weight-for-height (wasting), was compared with mortality, hospital readmission and cognition over 24-month follow-up.

RESULTS

At enrollment, wasting was more common in CM (16.7%) or SMA (15.9%) than CC (4.7%) (both p < 0.0001), and being underweight was more common in SMA (27.0%) than CC (12.8%; p = 0.001), while prevalence of stunting was similar in all three groups. By 6-month follow-up, prevalence of wasting or being underweight did not differ significantly between children with severe malaria and CC. Undernutrition at enrollment was not associated with mortality or hospital readmission, but children who were underweight or stunted at baseline had lower cognitive z-scores than those who were not {underweight, mean difference [95% confidence interval (CI)] -0.98 (-1.66, -0.31), -0.72 (-1.16, -0.27) and -0.61 (-1.08, -0.13); and stunted, -0.70 (-1.25, -0.15), -0.73 (-1.16, -0.31) and -0.61 (-0.96, -0.27), for CM, SMA and CC, respectively}.

CONCLUSION

In children with severe malaria, wasting and being underweight return to population levels after treatment. However, being stunted or underweight at enrollment was associated with worse long-term cognition in both CC and children with severe malaria.

Performance of Automated Point-of-Care Respiratory Rate Counting versus Manual Counting in Children under Five Admitted with Severe Febrile Illness to Kisantu Hospital, DR Congo

To improve the early recognition of danger signs in children with severe febrile illness in low resource settings, WHO promotes automated respiratory rate (RR) counting, but its performance is unknown in this population. Therefore, we prospectively evaluated the field performance of automated point-of-care plethysmography-based RR counting in hospitalized children with severe febrile illness (<5 years) in DR Congo. A trained research nurse simultaneously counted the RR manually (comparative method) and automatically with the Masimo Rad G pulse oximeter. Valid paired RR measurements were obtained in 202 (83.1%) children, among whom 43.1% (87/202) had fast breathing according to WHO criteria based on manual counting. Automated counting frequently underestimated the RR (median difference of -1 breath/minute; p2.5-p97.5 limits of agreement: -34-6), particularly at higher RR. This resulted in a failure to detect fast breathing in 24.1% (21/87) of fast breathing children (positive percent agreement: 75.9%), which was not explained by clinical characteristics (p > 0.05). Children without fast breathing were mostly correctly classified (negative percent agreement: 98.3%). In conclusion, in the present setting the automated RR counter performed insufficiently to facilitate the early recognition of danger signs in children with severe febrile illness, given wide limits of agreement and a too low positive percent agreement.

Factors Associated with Prolonged Hospital Length of Stay in Adults with Imported Falciparum Malaria-An Observational Study from a Tertiary Care University Hospital in Berlin, Germany

Outcome of falciparum malaria is largely influenced by the standard of care provided, which in turn depends on the available medical resources. Worldwide, the COVID-19 pandemic has had a major impact on the availability of these resources, even in resource-rich healthcare systems such as Germany's. The present study aimed to determine the under-explored factors associated with hospital length of stay (LOS) in imported falciparum malaria to identify potential targets for improving management. This retrospective observational study used multivariate Cox proportional hazard regression with time to discharge as an endpoint for adults hospitalized between 2001 and 2015 with imported falciparum malaria in the Charité University Hospital, Berlin. The median LOS of the 535 cases enrolled was 3 days (inter-quartile range, IQR, 3-4 days). The likelihood of being discharged by day 3 strongly decreased with severe malaria (hazard ratio, HR, 0.274; 95% Confidence interval, 95%CI: 0.190-0.396) and by 40% with each additional presenting complication (HR, 0.595; 95%CI: 0.510-0.694). The 55 (10.3%) severe cases required a median LOS of 7 days (IQR, 5-12 days). In multivariate analysis, occurrence of shock (adjusted HR, aHR, 0.438; 95%CI 0.220-0.873), acute pulmonary oedema or acute respiratory distress syndrome (aHR, 0.450; 95%CI: 0.223-0.874), and the need for renal replacement therapy (aHR, 0.170; 95%CI: 0.063-0.461) were independently associated with LOS. All patients survived to discharge. This study illustrates that favourable outcomes can be achieved with high-standard care in imported falciparum malaria. Early recognition of disease severity together with targeted supportive care can lead to avoidance of manifest organ failure, thereby potentially decreasing LOS and alleviating pressure on bed capacities.

Artesunate for the treatment of severe malaria: A retrospective review of patients admitted to two tertiary hospital intensive care units in Johannesburg, South Africa

Background

Globally, malaria is one of the six major causes of deaths from communicable diseases. In South Africa, malaria is known to be endemic in three provinces. Two large trials, AQUAMAT and SEAQUAMAT, demonstrated the superiority of intravenous (IV) artesunate compared to quinine. A systematic review (including the above trials) demonstrated a mortality benefit for adult patients treated with artesunate, but included studies that were conducted in Asia with no adult data available for Africa. Given the lack of local data, we conducted this study to investigate the use of artesunate for the treatment of severe malaria at two academic adult intensive care units (ICUs) in Johannesburg.

Methods

We undertook a retrospective patient record review. All patients admitted to the two ICUs and treated for severe malaria using artesunate were included. The study period extended from April 2010 to April 2014. The primary outcome was to determine the observed mortality and relate it to the predicted mortality based on the Acute Physiology and Chronic Health Evaluation (APACHE II) severity of illness score. The ratio of the observed mortality to the expected mortality based on the APACHE II severity of illness score provides a standardised mortality ratio (SMR). Clinical and laboratory parameters data were analysed.

Results

There were 56 patients included in the study, of which 40 were male (71.4%). The mean APACHE II score was 19 (standard deviation 5.4). We observed a lower than predicted mortality rate of 21.4% (SMR 0.66). Human immunodeficiency virus (HIV) was the most prevalent comorbidity (32%). There was no travel history in 26.8% of patients. Heart rate, respiratory rate and Glasgow Coma Scale (GCS) all improved significantly from admission to the time of discharge (p ≤ 0.01). Acidaemia, bilirubin, urea and bleeding risk (platelet count) also improved (p ≤ 0.01). Mechanical ventilation was associated with an increased risk of death (OR 35; CI 7.0–182).

Conclusion

In this retrospective two-centre study, IV artesunate was associated with a lower than predicted mortality in adult patients with severe malaria requiring ICU admission.

Acute Kidney Injury and Jaundice in a Patient With Concurrent Severe Malaria and Acute Exacerbation of Hepatitis B

Patients chronically infected with hepatitis B virus (HBV) may travel to areas with high endemicity of malaria. The overlap between malaria and HBV infection can be clinically severe and present a diagnostic challenge as both diseases manifest similar symptoms. This case describes a fatal case of a 43-year-old man with chronic HBV infected with Plasmodium falciparum malaria that presents as acute kidney injury (AKI) and jaundice following a trip to malaria-endemic region. Despite administering antimalarial and 6 courses of renal replacement therapy, the patient’s clinical condition did not improve, leading to septic shock, multi-organ dysfunction, and eventually, death. AKI and jaundice are commonly seen in severe P. falciparum malaria, as well as acute exacerbation of chronic HBV. This case emphasizes the importance to consider malarial screening when evaluating sick returning travelers, even in those with underlying chronic HBV. Given the severity of coinfection, prompt identification of this overlap can avert the rapid deterioration of severe malaria by early administration of intravenous artesunate and renal replacement therapy.