Biomarkers of post-discharge mortality among children with complicated severe acute malnutrition

Post-discharge complications and hospital readmissions are associated with nutritional risk and malnutrition status in a cohort of Canadian pediatric patients

BACKGROUND

This study constitutes a secondary analysis of a prospective cohort aiming to evaluate the potential correlation between nutritional risk and status at admission with the occurrence of post-discharge complications and hospital readmissions in children receiving care at high resource Centres.

METHODS

Data was collected from 5 Canadian tertiary pediatric Centers between 2012 and 2016. Nutritional risk and status were evaluated at hospital admission with validated tools (STRONGkids and Subjective Global Nutrition Assessment [SGNA]) and anthropometric measurements. Thirty days after discharge, occurrence of post-discharge complications and hospital readmission were documented.

RESULTS

A total of 360 participants were included in the study (median age, 6.1 years; median length of stay, 5 days). Following discharge, 24.1% experienced complications and 19.5% were readmitted to the hospital. The odds of experiencing complications were nearly tripled for participants with a high nutritional risk compared to a low risk (OR = 2.85; 95% CI [1.08-7.54]; P = 0.035) and those whose caregivers reported having a poor compared to a good appetite (OR = 2.96; 95% CI [1.59-5.50]; P < 0.001). According to SGNA, patients identified as malnourished had significantly higher odds of complications (OR, 1.92; 95% CI, 1.15-3.20; P = 0.013) and hospital readmission (OR, 1.95; 95% CI, 1.12-3.39; P = 0.017) than to those well-nourished.

CONCLUSIONS

This study showed that complications and readmission post-discharge are common, and these are more likely to occur in malnourished children compared to their well-nourished counterparts. Enhancing nutritional care during admission, at discharge and in the community may be an area for future outcome optimization.

Mitochondrial perturbations in low-protein-diet-fed mice are associated with altered neutrophil development and effector functions

Severe malnutrition is associated with infections, namely lower respiratory tract infections (LRTIs), diarrhea, and sepsis, and underlies the high risk of morbidity and mortality in children under 5 years of age. Dysregulations in neutrophil responses in the acute phase of infection are speculated to underlie these severe adverse outcomes; however, very little is known about their biology in this context. Here, in a lipopolysaccharide-challenged low-protein diet (LPD) mouse model, as a model of malnutrition, we show that protein deficiency disrupts neutrophil mitochondrial dynamics and ATP generation to obstruct the neutrophil differentiation cascade. This promotes the accumulation of atypical immature neutrophils that are incapable of optimal antimicrobial response and, in turn, exacerbate systemic pathogen spread and the permeability of the alveolocapillary membrane with the resultant lung damage. Thus, this perturbed response may contribute to higher mortality risk in malnutrition. We also offer a nutritional therapeutic strategy, nicotinamide, to boost neutrophil-mediated immunity in LPD-fed mice.

Malnutrition enteropathy in Zambian and Zimbabwean children with severe acute malnutrition: A multi-arm randomized phase II trial

Malnutrition underlies almost half of all child deaths globally. Severe Acute Malnutrition (SAM) carries unacceptable mortality, particularly if accompanied by infection or medical complications, including enteropathy. We evaluated four interventions for malnutrition enteropathy in a multi-centre phase II multi-arm trial in Zambia and Zimbabwe and completed in 2021. The purpose of this trial was to identify therapies which could be taken forward into phase III trials. Children of either sex were eligible for inclusion if aged 6-59 months and hospitalised with SAM (using WHO definitions: WLZ <-3, and/or MUAC <11.5 cm, and/or bilateral pedal oedema), with written, informed consent from the primary caregiver. We randomised 125 children hospitalised with complicated SAM to 14 days treatment with (i) bovine colostrum (n = 25), (ii) N-acetyl glucosamine (n = 24), (iii) subcutaneous teduglutide (n = 26), (iv) budesonide (n = 25) or (v) standard care only (n = 25). The primary endpoint was a composite of faecal biomarkers (myeloperoxidase, neopterin, α1-antitrypsin). Laboratory assessments, but not treatments, were blinded. Per-protocol analysis used ANCOVA, adjusted for baseline biomarker value, sex, oedema, HIV status, diarrhoea, weight-for-length Z-score, and study site, with pre-specified significance of P < 0.10. Of 143 children screened, 125 were randomised. Teduglutide reduced the primary endpoint of biomarkers of mucosal damage (effect size -0.89 (90% CI: -1.69,-0.10) P = 0.07), while colostrum (-0.58 (-1.4, 0.23) P = 0.24), N-acetyl glucosamine (-0.20 (-1.01, 0.60) P = 0.67), and budesonide (-0.50 (-1.33, 0.33) P = 0.32) had no significant effect. All interventions proved safe. This work suggests that treatment of enteropathy may be beneficial in children with complicated malnutrition. The trial was registered at ClinicalTrials.gov with the identifier NCT03716115.

Effects of L-Carnitine Supplementation on the Rate of Weight Gain and Biomarkers of Environmental Enteric Dysfunction in Children with Severe Acute Malnutrition: A Double-Blind Randomized Controlled Clinical Trial

BACKGROUND

Severe acute malnutrition (SAM) is a major public health concern among low- and middle-income countries, where the majority of the children encountering this acute form of malnutrition suffer from environmental enteric dysfunction (EED). However, evidence regarding the effects of L-carnitine supplementation on the rate of weight gain and EED biomarkers in malnourished children is limited.

OBJECTIVES

We aimed to investigate the role of L-carnitine supplementation on the rate of weight gain, duration of hospital stays, and EED biomarkers among children with SAM.

METHODS

A prospective, double-blind, placebo-controlled, randomized clinical trial was conducted at the Nutritional Rehabilitation Unit (NRU) of Dhaka Hospital, International Centre for Diarrheal Disease Research, Bangladesh. Children with SAM aged 9-24 mo were randomly assigned to receive commercial L-carnitine syrup (100 mg/kg/d) or placebo for 15 d in addition to standard of care. A total of 98 children with Weight-for-Length-z-score (WLZ) < -3 Standard deviation were enrolled between October 2021 and March 2023. Analyses were conducted on an intention-to-treat basis.

RESULTS

The primary outcome variable, "rate of weight gain," was comparable between L-carnitine and placebo groups (2.09 ± 2.23 compared with 2.07 ± 2.70; P = 0.973), which was consistent even after adjusting for potential covariates (age, sex, Weight-for-Age z-score, asset index, and WASH practices) through linear regression [ß: 0.37; 95% confidence interval (CI): -0.63,1.37; P = 0.465]. The average hospital stay was ∼4 d. The results of adjusted median regression showed that following intervention, there was no significant difference in the EED biomarkers among the treatment arms; Myeloperoxidase (ng/mL) [ß: -1342.29; 95% CI: -2817.35, 132.77; P = 0.074], Neopterin (nmol/L) [ß: -153.33; 95% CI: -556.58, 249.91; P = 0.452], alpha-1-antitrypsin (mg/mL) [ß: 0.05; 95% CI: -0.15, 0.25; P = 0.627]. Initial L-carnitine (μmol/L) levels (median, interquartile range) for L-carnitine compared with placebo were 54.84 (36.0, 112.9) and 59.74 (45.7, 96.0), whereas levels after intervention were 102.05 (60.9, 182.1) and 105.02 (73.1, 203.7).

CONCLUSIONS

Although our study findings suggest that L-carnitine bears no additional effect on SAM, we recommend clinical trials with a longer duration of supplementation, possibly with other combinations of interventions, to investigate further into this topic of interest. This trial was registered at clinicaltrials.gov as NCT05083637.

Inflammation and epithelial repair predict mortality, hospital readmission, and growth recovery in complicated severe acute malnutrition

Severe acute malnutrition (SAM) is the most high-risk form of undernutrition, particularly when children require hospitalization for complications. Complicated SAM is a multisystem disease with high inpatient and postdischarge mortality, especially in children with comorbidities such as HIV; however, the underlying pathogenesis of complicated SAM is poorly understood. Targeted multiplex biomarker analysis in children hospitalized with SAM (n = 264) was conducted on plasma samples, and inflammatory markers were assessed on stool samples taken at recruitment, discharge, and 12 to 24 and 48 weeks after discharge from three hospitals in Zimbabwe and Zambia. Compared with adequately nourished controls (n = 173), we found that at baseline, complicated SAM was characterized by systemic, endothelial, and intestinal inflammation, which was exacerbated by HIV infection. This persisted over 48 weeks despite nutritional recovery and was associated with children's outcomes. Baseline plasma concentrations of vascular endothelial growth factor, glucagon-like peptide-2, and intestinal fatty acid-binding protein were independently associated with lower mortality or hospital readmission over the following 48 weeks. Following principal components analysis of baseline biomarkers, higher scores of a component representing growth factors was associated with greater weight-for-height z score recovery and lower mortality or hospital readmission over the 48 weeks. Conversely, components representing higher gut and systemic inflammation were associated with higher mortality or hospital readmission. These findings highlight the interplay between inflammation, which damages tissues, and growth factors, which mediate endothelial and epithelial regeneration, and support further studies investigating interventions to reduce inflammation and promote epithelial repair as an approach to reducing mortality and improving nutritional recovery.

Pediatric post-discharge mortality in resource-poor countries: a systematic review and meta-analysis

Background

Under-five mortality remains concentrated in resource-poor countries. Post-discharge mortality is becoming increasingly recognized as a significant contributor to overall child mortality. With a substantial recent expansion of research and novel data synthesis methods, this study aims to update the current evidence base by providing a more nuanced understanding of the burden and associated risk factors of pediatric post-discharge mortality after acute illness.

Methods

Eligible studies published between January 1, 2017 and January 31, 2023, were retrieved using MEDLINE, Embase, and CINAHL databases. Studies published before 2017 were identified in a previous review and added to the total pool of studies. Only studies from countries with low or low-middle Socio-Demographic Index with a post-discharge observation period greater than seven days were included. Risk of bias was assessed using a modified version of the Joanna Briggs Institute critical appraisal tool for prevalence studies. Studies were grouped by patient population, and 6-month post-discharge mortality rates were quantified by random-effects meta-analysis. Secondary outcomes included post-discharge mortality relative to in-hospital mortality, pooled risk factor estimates, and pooled post-discharge Kaplan-Meier survival curves. PROSPERO study registration: #CRD42022350975.

Findings

Of 1963 articles screened, 42 eligible articles were identified and combined with 22 articles identified in the previous review, resulting in 64 total articles. These articles represented 46 unique patient cohorts and included a total of 105,560 children. For children admitted with a general acute illness, the pooled risk of mortality six months post-discharge was 4.4% (95% CI: 3.5%-5.4%, I2 = 94.2%, n = 11 studies, 34,457 children), and the pooled in-hospital mortality rate was 5.9% (95% CI: 4.2%-7.7%, I2 = 98.7%, n = 12 studies, 63,307 children). Among disease subgroups, severe malnutrition (12.2%, 95% CI: 6.2%-19.7%, I2 = 98.2%, n = 10 studies, 7760 children) and severe anemia (6.4%, 95% CI: 4.2%-9.1%, I2 = 93.3%, n = 9 studies, 7806 children) demonstrated the highest 6-month post-discharge mortality estimates. Diarrhea demonstrated the shortest median time to death (3.3 weeks) and anemia the longest (8.9 weeks). Most significant risk factors for post-discharge mortality included unplanned discharges, severe malnutrition, and HIV seropositivity.

Interpretation

Pediatric post-discharge mortality rates remain high in resource-poor settings, especially among children admitted with malnutrition or anemia. Global health strategies must prioritize this health issue by dedicating resources to research and policy innovation.

Funding

No specific funding was received.

Association between severe acute malnutrition in childhood and hematological disorders in adulthood: the Lwiro follow-up study in the Eastern Democratic Republic of the Congo

BACKGROUND

Despite growing evidence on the short-term deleterious effects of severe acute malnutrition (SAM) in childhood on hematopoiesis, little is known about the long-term hematological effects of SAM in low-income countries (LICs). Our study explored the association between childhood SAM and hematological disorders in adults 11 to 30 years after post-SAM nutritional rehabilitation.

METHODS

This follow up study investigated 97 adults (mean age 32 years) treated for SAM during childhood in eastern Democratic Republic of the Congo (DRC) between 1988 and 2007. Participants were compared to 97 aged- and sex-matched adult controls living in the same community with no history of SAM. Outcomes of interest were hematological characteristics and disorders in adulthood, assessed by various biological markers. Logistic and linear regression models were used to estimate the association between SAM in childhood and risk of hematological abnormalities.

RESULTS

Compared to the unexposed, the exposed had higher mean white blood cells (/μl) [+ 840 (179 to 1501), p = 0.013], neutrophils [+ 504 (83 to 925), p = 0.019] and platelets (*103) [11.9 (8.1 to 17.9), p = 0.038] even after adjustment for food consumption in adulthood. No difference was observed in red blood cells (RBC), hemoglobin and erythrocytes parameters. With regard to the risk of hematological disorders, in contrast to the unexposed, exposed subjects had a risk of leukocytosis approximately three times higher [adjusted OR (95% CI): 2.98 (1.01 to 8.79), p = 0.048]. No difference was observed in terms of anemia, leukopenia, increased platelets and thrombocytopenia between the 2 groups.

CONCLUSION

Adults with a history of SAM in childhood have hematological characteristics that would be markers associated with chronic low-grade inflammatory or infectious diseases in an environment with no nutritional transition. Larger cohort studies with bone marrow analyses could provide further understanding of the impact of SAM on the overall hematological profile in adult life.

Inflammation: the driver of poor outcomes among children with severe acute malnutrition?

Severe acute malnutrition (SAM) is the most life-threatening form of undernutrition and underlies at least 10% of all deaths among children younger than 5 years in low-income countries. SAM is a complex, multisystem disease, with physiological perturbations observed in conjunction with the loss of lean mass, including structural and functional changes in many organ systems. Despite the high mortality burden, predominantly due to infections, the underlying pathogenic pathways remain poorly understood. Intestinal and systemic inflammation is heightened in children with SAM. Chronic inflammation and its consequent immunomodulation may explain the increased morbidity and mortality from infections in children with SAM, both during hospitalization and in the longer term after discharge. Recognition of the role of inflammation in SAM is critical in considering new therapeutic targets in this disease, which has not seen a transformational approach to treatment for several decades. This review highlights the central role of inflammation in the wide-ranging pathophysiology of SAM, as well as identifying potential interventions that have biological plausibility based on evidence from other inflammatory syndromes.

Severe acute malnutrition promotes bacterial binding over proinflammatory cytokine secretion by circulating innate immune cells

Children with severe acute malnutrition (SAM) have high infectious mortality and morbidity, implicating defects in their immune defenses. We hypothesized that circulating innate immune cells from children (0 to 59 months) hospitalized with SAM in Zambia and Zimbabwe (n = 141) have distinct capacity to respond to bacteria relative to adequately nourished healthy controls (n = 92). SAM inpatients had higher neutrophil and monocyte Escherichia coli binding capacity but lower monocyte activation and proinflammatory mediator secretion in response to lipopolysaccharide or heat-killed Salmonella typhimurium than controls. Among SAM cases, wasting severity was negatively associated with cytokine secretion, children with HIV had lower monocyte activation, and the youngest children released the least myeloperoxidase upon stimulation. Inpatient bacterial binding capacity and monocyte activation were associated with higher odds of persistent SAM at discharge, a risk factor for subsequent mortality. Thus, SAM shifts innate immune cell function, favoring bacterial containment over proinflammatory activation, which may contribute to health deficits after discharge.

Changes in polyunsaturated fatty acids during treatment of malnourished children may be insufficient to reach required essential fatty acid levels - A randomised controlled trial

BACKGROUND & AIMS

Severe acute malnutrition (SAM) is a global concern. Studies on the impact of ready-to-use therapeutic foods (RUTFs) on polyunsaturated fatty acids (PUFA) are almost non-existent. The aim was to investigate the change in whole-blood PUFA and nutrition and health markers among Cambodian children with SAM after treatment with RUTFs.

METHODS

The trial was an 8-week randomised clinical trial of the effectiveness of locally produced fish-based RUTF (L-RUTF) vs standard milk-based RUFT (S-RUTF). Whole-blood fatty acids were analysed using dried blood spots. Nutrition and health markers were assessed using anthropometric assessment and blood samples for markers of inflammation. The trial was conducted at the National Pediatric Hospital, Phnom Penh, Cambodia, with one hundred and twenty-one 6-59-month-old children in treatment for SAM.

RESULTS

L-RUTF had a higher content of n-3 PUFA and a higher content of arachidonic acid (AA) and docosahexaenoic acid (DHA), while S-RUTF had the highest content of n-6 PUFA. At baseline, the children presented with a Mead acid level in whole-blood of around 0.08% of total fatty acids (FA%) and an omega-3 index of ∼0.91 ± 0.44. After eight weeks of S-RUTF treatment, linoleic acid (LA), AA, n-6/n-3 PUFA ratio, and Mead acid levels were increased. The L-RUTF intervention did not change the whole-blood PUFAs from baseline. At discharge, the children in the L-RUTF group had a lower n-6/n-3 PUFA ratio than the children in the S-RUTF group, driven by a lower alpha-linolenic acid (ALA) (0.20 vs 0.27 FA%, p = 0.004) and lower LA (15.77 vs 14.21 FA%, p = 0.018) with no significant differences in AA or DHA levels. Weight-for-height z-score at discharge was negatively associated with total PUFA (β -1.4 FA%, 95%CI. -2.7; -0.1), n-6 LCPUFA (β -1.3 FA%, 95%CI. -1.3; -0.3), and AA (β -0.6 FA%, 95%CI. -1.0; -0.2). Age-adjusted height was negatively associated with the Mead acid:AA ratio (β -1.2 FA%, 95%CI. -2.2; -0.2). No significant change was seen in inflammation markers within groups or between groups during treatment, and n-3 and n-6 PUFAs were not associated with markers of inflammation or haemoglobin status at discharge.

CONCLUSION

The trial found that whole-blood markers of PUFA status were low in children at admission and discharge from SAM treatment, indicating that the currently recommended composition of RUTFs are not able to correct their compromised essential fatty acid status. The higher content of DHA and AA in L-RUTF did not give rise to any improvement in PUFA status. No changes in health markers or associations between PUFA and health markers were found.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02907424.

Malnourished Microbes: Host-Microbiome Interactions in Child Undernutrition

Childhood undernutrition is a major global health burden that is only partially resolved by nutritional interventions. Both chronic and acute forms of child undernutrition are characterized by derangements in multiple biological systems including metabolism, immunity, and endocrine systems. A growing body of evidence supports a role of the gut microbiome in mediating these pathways influencing early life growth. Observational studies report alterations in the gut microbiome of undernourished children, while preclinical studies suggest that this can trigger intestinal enteropathy, alter host metabolism, and disrupt immune-mediated resistance against enteropathogens, each of which contribute to poor early life growth. Here, we compile evidence from preclinical and clinical studies and describe the emerging pathophysiological pathways by which the early life gut microbiome influences host metabolism, immunity, intestinal function, endocrine regulation, and other pathways contributing to child undernutrition. We discuss emerging microbiome-directed therapies and consider future research directions to identify and target microbiome-sensitive pathways in child undernutrition.

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.

Skeletal manifestations of disease experience: Length of illness and porous cranial lesion formation in a contemporary juvenile mortality sample

OBJECTIVES

Porous lesions of the orbit (cribra orbitalia [CO]) and cranial vault (porotic hyperostosis [PH]) are used as skeletal indicators of childhood stress. Because they are understudied in contemporary populations, their relationship to disease experience is poorly understood. This paper examines the relationship between length of childhood illness and CO/PH formation in a clinically documented sample. "Turning points," which identify the window for lesion formation for CO/PH, are defined, implications for hidden heterogeneity in frailty are considered.

METHODS

Data are from 333 (199 males; 134 females) pediatric postmortem computed tomography scans. Individuals died in New Mexico (2011-2019) and are 0.5 to 15.99 years (mean = 7.1). Length of illness was estimated using information from autopsy and field reports. Logistic regression was used to estimate predicted probabilities, odds ratios, and the temporal window for lesion formation.

RESULTS

Illness, single bouts, or cumulative episodes lasting over 1 month is associated with higher odds of CO; individuals who were never sick have lower odds of having PH. This relationship was consistent for fatal and incidental illnesses that did not cause death. The developmental window for CO formation appears to close at 8 years.

CONCLUSIONS

Those ill for over 1 month are more likely to have CO/PH than those with acute illnesses. Some individuals lived sufficiently long to form CO/PH but died of illness. Others with lesions died of circumstances unrelated to disease. This indicates hidden variation in robusticity even among ill individuals with CO/PH, which is vital in interpreting lesion frequencies in the archeological record.

Predictive value of clinician impression for readmission and postdischarge mortality among neonates and young children in Dar es Salaam, Tanzania and Monrovia, Liberia

BACKGROUND

There are no validated clinical decision aids to identify neonates and young children at risk of hospital readmission or postdischarge mortality in sub-Saharan Africa, leaving the decision to discharge a child to a clinician's impression. Our objective was to determine the precision of clinician impression to identify neonates and young children at risk for readmission and postdischarge mortality.

METHODS

We conducted a survey study nested in a prospective observational cohort of neonates and children aged 1-59 months followed 60 days after hospital discharge from Muhimbili National Hospital in Dar es Salaam, Tanzania or John F. Kennedy Medical Center in Monrovia, Liberia. Clinicians who discharged each enrolled patient were surveyed to determine their perceived probability of the patient's risk of 60-day hospital readmission or postdischarge mortality. We calculated the area under the precision-recall curve (AUPRC) to determine the precision of clinician impression for both outcomes.

RESULTS

Of 4247 discharged patients, 3896 (91.7%) had available clinician surveys and 3847 (98.7%) had 60-day outcomes available: 187 (4.8%) were readmitted and 120 (3.1%) died within 60 days of hospital discharge. Clinician impression had poor precision in identifying neonates and young children at risk of hospital readmission (AUPRC: 0.06, 95% CI: 0.04 to 0.08) and postdischarge mortality (AUPRC: 0.05, 95% CI: 0.03 to 0.08). Patients for whom clinicians attributed inability to pay for future medical treatment as the reason for risk for unplanned hospital readmission had 4.76 times the odds hospital readmission (95% CI: 1.31 to 17.25, p=0.02).

CONCLUSIONS

Given the poor precision of clinician impression alone to identify neonates and young children at risk of hospital readmission and postdischarge mortality, validated clinical decision aids are needed to aid in the identification of young children at risk for these outcomes.

Associations between Stunting, Wasting and Body Composition: A Longitudinal Study in 6- to 15-Month-Old Kenyan Children

BACKGROUND

Early growth and body composition may influence the risk of obesity and health in adulthood. Few studies have examined how undernutrition is associated with body composition in early life.

OBJECTIVES

We assessed stunting and wasting as correlates of body composition in young Kenyan children.

METHODS

Nested in a randomized controlled nutrition trial, this longitudinal study assessed fat and fat-free mass (FM, FFM) using deuterium dilution technique among children at age 6 and 15 months. This trial was registered at http://controlled-trials.com/ (ISRCTN30012997). Cross-sectional and longitudinal associations between z-score categories of length-for-age (LAZ) or weight-for-length (WLZ) and FM, FFM, fat mass index (FMI), fat-free mass index (FFMI), triceps, and subscapular skinfolds were analyzed by linear mixed models.

RESULTS

Among the 499 children enrolled, breastfeeding declined from 99% to 87%, stunting increased from 13% to 32%, and wasting remained at 2% to 3% between 6 and 15 mo. Compared with LAZ >0, stunted children had a 1.12 kg (95% CI: 0.88, 1.36; P < 0.001) lower FFM at 6 mo and increased to 1.59 kg (95% CI: 1.25, 1.94; P < 0.001) at 15 mo, corresponding to differences of 18% and 17%, respectively. When analyzing FFMI, the deficit in FFM tended to be less than proportional to children's height at 6 mo (P ≤ 0.060) but not at 15 mo (P > 0.40). Stunting was associated with 0.28 kg (95% CI: 0.09, 0.47; P = 0.004) lower FM at 6 mo. However, this association was not significant at 15 mo, and stunting was not associated with FMI at any time point. A lower WLZ was generally associated with lower FM, FFM, FMI, and FFMI at 6 and 15 mo. Differences in FFM, but not FM, increased with time, whereas FFMI differences did not change, and FMI differences generally decreased with time.

CONCLUSIONS

Overall, low LAZ and WLZ among young Kenyan children were associated with reduced lean tissue, which may have long-term health consequences.

Effects of probiotic and synbiotic supplementation on ponderal and linear growth in severely malnourished young infants in a randomized clinical trial

Severe acute malnutrition (SAM) is a major global public health problem. We aimed to assess the effects of probiotic and synbiotic supplementation on rate of weight gain and change in length in young SAM infants. This study was substudy of a single-blind randomized clinical trial (NCT0366657). During nutritional rehabilitation, 67 <6 months old SAM infants were enrolled and randomized to receive either probiotic (Bifidobacterium. infantis EVC001) or synbiotic (B. infantis EVC001 + Lacto-N-neotetraose [LNnT]) or placebo (Lactose) for four weeks and were followed for four more weeks after supplementation. In multivariable linear regression model, the mean rate of weight gain in the probiotic arm compared to placebo was higher by 2.03 unit (P < 0.001), and 1.13 unit (P = 0.030) in the synbiotic arm. In linear mixed-effects model, mean WAZ was higher by 0.57 unit (P = 0.018) in probiotic arm compared to placebo. Although not statistically significant, delta length for age z score (LAZ) trended to be higher among children in probiotc (β = 0.25) and synbiotic (β = 0.26) arms compared to placebo in multivariable linear regression model. Our study describes that young SAM infants had a higher rate of weight gain when supplemented with probiotic alone, compared to their counterparts with either synbiotic or placebo.

The Childhood Acute Illness and Nutrition (CHAIN) network nested case-cohort study protocol: a multi-omics approach to understanding mortality among children in sub-Saharan Africa and South Asia

Introduction: Many acutely ill children in low- and middle-income settings have a high risk of mortality both during and after hospitalisation despite guideline-based care. Understanding the biological mechanisms underpinning mortality may suggest optimal pathways to target for interventions to further reduce mortality. The Childhood Acute Illness and Nutrition (CHAIN) Network ( www.chainnnetwork.org) Nested Case-Cohort Study (CNCC) aims to investigate biological mechanisms leading to inpatient and post-discharge mortality through an integrated multi-omic approach. Methods and analysis; The CNCC comprises a subset of participants from the CHAIN cohort (1278/3101 hospitalised participants, including 350 children who died and 658 survivors, and 270/1140 well community children of similar age and household location) from nine sites in six countries across sub-Saharan Africa and South Asia. Systemic proteome, metabolome, lipidome, lipopolysaccharides, haemoglobin variants, toxins, pathogens, intestinal microbiome and biomarkers of enteropathy will be determined. Computational systems biology analysis will include machine learning and multivariate predictive modelling with stacked generalization approaches accounting for the different characteristics of each biological modality. This systems approach is anticipated to yield mechanistic insights, show interactions and behaviours of the components of biological entities, and help develop interventions to reduce mortality among acutely ill children. Ethics and dissemination. The CHAIN Network cohort and CNCC was approved by institutional review boards of all partner sites. Results will be published in open access, peer reviewed scientific journals and presented to academic and policy stakeholders. Data will be made publicly available, including uploading to recognised omics databases. Trial registration NCT03208725.

A pragmatic randomized controlled trial of standard care versus steroids plus standard care for treatment of pneumonia in adults admitted to Kenyan hospitals (SONIA)

Background: It is unclear if adjunctive steroid therapy reduces mortality in community-acquired pneumonia, as very few studies have had mortality as a primary outcome. This question has become even more relevant following demonstration of a mortality benefit of dexamethasone when used in patients with COVID-19 who had severe disease. This has led to increased prescription of steroids in adults with community acquired pneumonia in low-resource settings even when their COVID-19 diagnosis is uncertain due to low testing rates. This pragmatic parallel randomised-controlled open-label trial will determine if adjunctive low-dose steroids for treatment of adults admitted to hospital with community acquired pneumonia whose SARS-CoV-2 status is either unknown or negative reduces mortality. Methods: We will enroll and randomize 2180 patients admitted with a clinical diagnosis of community acquired pneumonia into two arms; in Stratum A-participants will receive standard care for the treatment of community acquired pneumonia. In Stratum B-participants will receive a 10-day course of low-dose oral corticosteroids in addition to standard care. All participants will be followed up to 30 days post randomization and their final status recorded (alive or dead). An immunology sub study will be conducted on a subset of the trial participants (50 per arm) to determine the correlation of pre-existing and treatment induced immune and metabolic changes with study outcomes. Discussion: Mortality among adults admitted to hospital with community acquired pneumonia in resource-limited settings is high. Steroids are readily available in these settings. If the addition of steroids to standard care for community acquired pneumonia is found to be beneficial, this easily scalable intervention would significantly reduce the currently high mortality associated with the illness.

The genome sequence of the acorn piercer, Pammene fasciana (Linnaeus, 1761)

We present a genome assembly from an individual male Pammene fasciana (acorn piercer; Arthropoda; Insecta; Lepidoptera; Tortricidae). The genome sequence is 564 megabases in span. The majority of the assembly (99.94%) is scaffolded into 28 chromosomal pseudomolecules with the Z sex chromosome assembled. The complete mitochondrial genome was also assembled and is 16.4 kilobases in length.

Role of L-Carnitine supplementation on rate of weight gain and biomarkers of Environmental Enteric Dysfunction in children with severe acute malnutrition: A protocol for a double-blinded randomized controlled trial

BACKGROUND

Severe acute malnutrition (SAM) and environmental enteric dysfunction (EED) are highly prevalent among children residing in resource-limited countries like Bangladesh. L-carnitine may play a role in improving the growth and ameliorating the EED among nutritionally vulnerable children.

OBJECTIVE

To investigate the role of L-carnitine supplementation on the rate of weight gain, duration of hospital stays, and EED biomarkers among children with severe acute malnutrition.

METHODS

This study is a double-blinded, placebo-controlled, randomized clinical trial aiming to enroll diarrheal children with SAM between 9-24 months of both sexes attending the nutritional rehabilitation unit (NRU) of Dhaka Hospital of icddr,b. It is an ongoing trial including two arms where one arm receives L-carnitine supplementation, and the other arms receive a placebo for 15 days in addition to the existing standard treatment of SAM. The primary outcome is the rate of weight gain, and the secondary outcomes include duration of hospital stay and EED biomarkers. Outcomes are assessed at baseline and 15 days of post-intervention. We hypothesize that the L- carnitine supplementation for 15 days in children with SAM will improve the rate of weight gain and biomarkers of EED.

TRIAL REGISTRATION

ClinicalTrials.gov # NCT05083637. Date of registration: October 19, 2021.

Adipokines and coronary artery calcification in incident dialysis participants

PURPOSE

Adipokines have been associated with increased risk of cardiovascular disease. Our aim was to determine if adipokine levels are associated with coronary artery calcification (CAC) as well as all-cause mortality in incident dialysis patients.

METHODS

In patients new to dialysis, we prospectively investigated the association of adiponectin, leptin and resistin with coronary artery calcification measured by ECG-gated computer tomography. Participants were recruited a median of two months after starting dialysis.

RESULTS

The mean age was 50.0 (12.6) years and 31.1% were women. About 42% percent had BMI > 30. Higher adiponectin levels were inversely associated with CAC progression as change in Agatston score [-155.1 (-267.9, -42.2), p = 0.008] or change in CAC volumes between scans [-2.8 (-4.9, -0.6), p = 0.01]. Higher leptin levels were associated with CAC progression [110.4 (34.3-186.6), p = 0.005]. Decreased leptin [HR 0.5 (0.3-0.9), p = 0.05] was associated with all-cause mortality in adjusted models. There was no significant association between all-cause mortality and adiponectin [1.4 (0.6-3.4), p = 0.4] or resistin [HR 1.7 (0.5-5.0), p = 0.4].

CONCLUSION

High adiponectin protects against CAC progression, but is not associated with increased all-cause mortality. Higher leptin, as well as higher leptin to adiponectin ratio, is associated with CAC progression. Lower leptin levels were associated with all-cause mortality. The association of adipokines and cardiovascular disease in individuals on dialysis is complex and requires further study.

The Childhood Acute Illness and Nutrition (CHAIN) network nested case-cohort study protocol: a multi-omics approach to understanding mortality among children in sub-Saharan Africa and South Asia

Introduction: Many acutely ill children in low- and middle-income settings have a high risk of mortality both during and after hospitalisation despite guideline-based care. Understanding the biological mechanisms underpinning mortality may suggest optimal pathways to target for interventions to further reduce mortality. The Childhood Acute Illness and Nutrition (CHAIN) Network ( www.chainnnetwork.org) Nested Case-Cohort Study (CNCC) aims to investigate biological mechanisms leading to inpatient and post-discharge mortality through an integrated multi-omic approach. Methods and analysis; The CNCC comprises a subset of participants from the CHAIN cohort (1278/3101 hospitalised participants, including 350 children who died and 658 survivors, and 270/1140 well community children of similar age and household location) from nine sites in six countries across sub-Saharan Africa and South Asia. Systemic proteome, metabolome, lipidome, lipopolysaccharides, haemoglobin variants, toxins, pathogens, intestinal microbiome and biomarkers of enteropathy will be determined. Computational systems biology analysis will include machine learning and multivariate predictive modelling with stacked generalization approaches accounting for the different characteristics of each biological modality. This systems approach is anticipated to yield mechanistic insights, show interactions and behaviours of the components of biological entities, and help develop interventions to reduce mortality among acutely ill children. Ethics and dissemination. The CHAIN Network cohort and CNCC was approved by institutional review boards of all partner sites. Results will be published in open access, peer reviewed scientific journals and presented to academic and policy stakeholders. Data will be made publicly available, including uploading to recognised omics databases. Trial registration NCT03208725.

Association between anthropometric criteria and body composition among children aged 6-59 months with severe acute malnutrition: a cross-sectional assessment from India

A multicentric study is being conducted in which children with severe acute malnutrition (SAM) aged 6–59 months are identified with only weight-for-height z-score (WHZ) < − 3 criteria. The present study aimed to assess associations of anthropometric parameters and body composition parameters, to improve treatment of SAM. We conducted a cross-section assessment using the enrolment data of children who participated in a multi-centric longitudinal controlled study from five Indian states. Fat-free mass (FFM) and fat mass (FM) were determined by bio-electrical impedance analysis (BIA). Six hundred fifty-nine children were enrolled in the study using WHZ < -3 criteria. Available data shows that WHZ, WAZ and BMIZ were significantly associated with FFMI while MUACZ was significantly associated with both FMI and FFMI. Children with both severe wasting and severe stunting had significantly lower FFMI compared to those who were only severely wasted. All forms of anthropometric deficits appear to adversely impact FFM and FM.

Trial registration

The study is registered with Clinical Trial Registration of India (Registration No.: CTRI/2020/09/028013 dated 24/09/2020).

Stunting Status and Exposure to Infection and Inflammation in Early Life Shape Antibacterial Immune Cell Function Among Zimbabwean Children

Background

Children who are stunted (length-for-age Z-score<-2) are at greater risk of infectious morbidity and mortality. Previous studies suggest that stunted children have elevated inflammatory biomarkers, but no studies have characterised their capacity to respond to new infections (i.e., their immune function). We hypothesised that antibacterial immune function would differ between stunted and non-stunted children and relate to their health and environment during early life.

Methods

We enrolled a cross-sectional cohort of 113 HIV-negative children nested within a longitudinal cluster-randomised controlled trial of household-level infant and young child feeding (IYCF) and water, sanitation and hygiene (WASH) interventions in rural Zimbabwe (SHINE; Clinical trials registration: NCT01824940). Venous blood was collected at 18 months of age and cultured for 24 h without antigen or with bacterial antigens: heat-killed Salmonella typhimurium (HKST) or Escherichia coli lipopolysaccharide (LPS). TNFα, IL-6, IL-8, IL-12p70, hepcidin, soluble (s)CD163, myeloperoxidase (MPO) and IFNβ were quantified in culture supernatants by ELISA to determine antigen-specific immune function. The effect of stunting status and early-life exposures (anthropometry, inflammation at 18 months, maternal health during pregnancy, household WASH) on immune function was tested in logit and censored log-normal (tobit) regression models.

Results

Children who were stunted (n = 44) had higher proportions (86.4% vs. 65.2%; 88.6% vs. 73.4%) and concentrations of LPS-specific IL-6 (geometric mean difference (95% CI): 3.46 pg/mL (1.09, 10.80), p = 0.035) and IL-8 (3.52 pg/mL (1.20, 10.38), p = 0.022) than non-stunted children (n = 69). Bacterial antigen-specific pro-inflammatory cytokine concentrations were associated with biomarkers of child enteropathy at 18 months and biomarkers of systemic inflammation and enteropathy in their mothers during pregnancy. Children exposed to the WASH intervention (n = 33) produced higher LPS- (GMD (95% CI): 10.48 pg/mL (1.84, 60.31), p = 0.008) and HKST-specific MPO (5.10 pg/mL (1.77, 14.88), p = 0.003) than children in the no WASH group (n = 80). There was no difference in antigen-specific immune function between the IYCF (n = 55) and no IYCF groups (n = 58).

Conclusions

Antibacterial immune function among 18-month-old children in a low-income setting was shaped by their stunting status and prior exposure to maternal inflammation and household WASH. Heterogeneity in immune function due to adverse exposures in early life could plausibly contribute to infection susceptibility.

Childhood mortality during and after acute illness in Africa and south Asia: a prospective cohort study

BACKGROUND

Mortality among children with acute illness in low-income and middle-income settings remains unacceptably high and the importance of post-discharge mortality is increasingly recognised. We aimed to explore the epidemiology of deaths among young children with acute illness across sub-Saharan Africa and south Asia to inform the development of interventions and improved guidelines.

METHODS

In this prospective cohort study, we enrolled children aged 2-23 months with acute illness, stratified by nutritional status defined by anthropometry (ie, no wasting, moderate wasting, or severe wasting or kwashiorkor), who were admitted to one of nine hospitals in six countries across sub-Saharan Africa and south Asia between Nov 20, 2016, and Jan 31, 2019. We assisted sites to comply with national guidelines. Co-primary outcomes were mortality within 30 days of hospital admission and post-discharge mortality within 180 days of hospital discharge. A priori exposure domains, including demographic, clinical, and anthropometric characteristics at hospital admission and discharge, as well as child, caregiver, and household-level characteristics, were examined in regression and survival structural equation models.

FINDINGS

Of 3101 children (median age 11 months [IQR 7-16]), 1120 (36·1%) had no wasting, 763 (24·6%) had moderate wasting, and 1218 (39·3%) had severe wasting or kwashiorkor. Of 350 (11·3%) deaths overall, 234 (66·9%) occurred within 30 days of hospital admission and 168 (48·0%) within 180 days of hospital discharge. 90 (53·6%) post-discharge deaths occurred at home. The proportion of children who died following discharge was relatively preserved across nutritional strata. Numerically large high-risk and low-risk groups could be disaggregated for early mortality and post-discharge mortality. Structural equation models identified direct pathways to mortality and multiple socioeconomic, clinical, and nutritional domains acting indirectly through anthropometric status.

INTERPRETATION

Among diverse sites in Africa and south Asia, almost half of mortality occurs following hospital discharge. Despite being highly predictable, these deaths are not addressed in current guidelines. A fundamental shift to a child-centred, risk-based approach to inpatient and post-discharge management is needed to further reduce childhood mortality, and clinical trials of these approaches with outcomes of mortality, readmission, and cost are warranted.

FUNDING

The Bill & Melinda Gates Foundation.

The role of albumin and the extracellular matrix on the pathophysiology of oedema formation in severe malnutrition

BACKGROUND

While fluid flows in a steady state from plasma, through interstitium, and into the lymph compartment, altered fluid distribution and oedema can result from abnormal Starling's forces, increased endothelial permeability or impaired lymphatic drainage. The mechanism of oedema formation, especially the primary role of hypoalbuminaemia, remains controversial. Here, we explored the roles of albumin and albumin-independent mechanisms in oedema formation among children with severe malnutrition (SM).

METHODS

We performed secondary analysis of data obtained from two independent clinical trials in Malawi and Kenya (NCT02246296 and NCT00934492). We then used an unconventional strategy of comparing children with kwashiorkor and marasmus by matching (discovery cohort, n = 144) and normalising (validation cohort, n = 98, 2 time points) for serum albumin. Untargeted proteomics was used in the discovery cohort to determine plausible albumin-independent mechanisms associated with oedema, which was validated using enzyme-linked immunosorbent assay and multiplex assays in the validation cohort.

FINDINGS

We demonstrated that low serum albumin is necessary but not sufficient to develop oedema in SM. We further found that markers of extracellular matrix (ECM) degradation rather than markers of EG degradation distinguished oedematous and non-oedematous children with SM.

INTERPRETATION

Our results show that oedema formation has both albumin-dependent and independent mechanisms. ECM integrity appears to have a greater role in oedema formation than EG shedding in SM.

FUNDING

Research Foundation Flanders (FWO), Thrasher Foundation (15122 and 9403), VLIR-UOS-Ghent University Global Minds Fund, Bill & Melinda Gates Foundation (OPP1131320), MRC/DfID/Wellcome Trust Global Health Trials Scheme (MR/M007367/1), Canadian Institutes of Health Research (156307), Wellcome Trust (WT083579MA).

Systemic inflammation and metabolic disturbances underlie inpatient mortality among ill children with severe malnutrition

Children admitted to hospital with an acute illness and concurrent severe malnutrition [complicated severe malnutrition (CSM)] have a high risk of dying. The biological processes underlying their mortality are poorly understood. In this case-control study nested within a multicenter randomized controlled trial among children with CSM in Kenya and Malawi, we found that blood metabolomic and proteomic profiles robustly differentiated children who died (n = 92) from those who survived (n = 92). Fatalities were characterized by increased energetic substrates (tricarboxylic acid cycle metabolites), microbial metabolites (e.g., propionate and isobutyrate), acute phase proteins (e.g., calprotectin and C-reactive protein), and inflammatory markers (e.g., interleukin-8 and tumor necrosis factor-α). These perturbations indicated disruptions in mitochondria-related bioenergetic pathways and sepsis-like responses. This study identified specific biomolecular disturbances associated with CSM mortality, revealing that systemic inflammation and bioenergetic deficits are targetable pathophysiological processes for improving survival of this vulnerable population.

Toll-Like Receptor-Induced Immune Responses During Early Childhood and Their Associations With Clinical Outcomes Following Acute Illness Among Infants in Sub-Saharan Africa

Severely ill children in low- and middle-income countries (LMICs) experience high rates of mortality from a broad range of infectious diseases, with the risk of infection-related death compounded by co-existing undernutrition. How undernutrition and acute illness impact immune responses in young children in LMICs remains understudied, and it is unclear what aspects of immunity are compromised in this highly vulnerable population. To address this knowledge gap, we profiled longitudinal whole blood cytokine responses to Toll-like receptor (TLR) ligands among severely ill children (n=63; 2-23 months old) with varied nutritional backgrounds, enrolled in the CHAIN Network cohort from Kampala, Uganda, and Kilifi, Kenya, and compared these responses to similar-aged well children in local communities (n=41). Cytokine responses to ligands for TLR-4 and TLR-7/8, as well as Staphylococcus enterotoxin B (SEB), demonstrated transient impairment in T cell function among acutely ill children, whereas innate cytokine responses were exaggerated during both acute illness and following clinical recovery. Nutritional status was associated with the magnitude of cytokine responses in all stimulated conditions. Among children who died following hospital discharge or required hospital re-admission, exaggerated production of interleukin-7 (IL-7) to all stimulation conditions, as well as leukopenia with reduced lymphocyte and monocyte counts, were observed. Overall, our findings demonstrate exaggerated innate immune responses to pathogen-associated molecules among acutely ill young children that persist during recovery. Heightened innate immune responses to TLR ligands may contribute to chronic systemic inflammation and dysregulated responses to subsequent infectious challenges. Further delineating mechanisms of innate immune dysregulation in this population should be prioritized to identify novel interventions that promote immune homeostasis and improve outcomes.

Guidance for Systematic Integration of Undernutrition in Attributing Cause of Death in Children

Minimally invasive tissue sampling (MITS) is increasingly being used to better understand causes of death in low-resource settings. Undernutrition (eg, wasting, stunting) is prevalent among children globally and yet not consistently coded or uniformly included on death certificates in MITS studies when present. Consistent and accurate attribution of undernutrition is fundamental to understanding its contribution to child deaths. In May 2020, members of the MITS Alliance Cause of Death Technical Working Group convened a panel of experts in public health, child health, nutrition, infectious diseases, and MITS to develop guidance for systematic integration of undernutrition, as assessed by anthropometry, in cause of death coding, including as part of the causal chain or as a contributing condition, in children <5 years of age. The guidance presented here will support MITS and other researchers, public health practitioners, and clinicians with a systematic approach to assigning and interpreting undernutrition in death certification.

Weight-for-Height Z-score Gain during Inpatient Treatment and Subsequent Linear Growth during Outpatient Treatment of Young Children with Severe Acute Malnutrition: A Prospective Study from Uganda

BACKGROUND

Linear catch-up growth after treatment of severe acute malnutrition (SAM) is low, and little is known about the association between ponderal and subsequent linear growth.

OBJECTIVE

The study assessed the association of weight-for-height z-score (WHZ) gain with subsequent linear growth during SAM treatment and examined its modifiers.

METHODS

This was a prospective study, nested in a trial (ISRCTN16454889), among 6-59-mo-old children treated for SAM in Uganda. Weight, total length (TL), and knee-heel length (KHL) were measured at admission, weekly during inpatient therapeutic care (ITC), at discharge, and fortnightly during outpatient therapeutic care (OTC) for 8 wk. Linear regression was used to assess the association between WHZ gain during ITC and linear growth during OTC.

RESULTS

Of 400 children, 327 were discharged to OTC and 290 were followed up for 8 wk. Mean WHZ gains were 0.45 in ITC and 1.24 in OTC, whereas mean height-for-age z-score (HAZ) declined by 0.41 during ITC and increased by 0.14 during OTC. WHZ gain during ITC was positively associated with HAZ, TL, and KHL gains during OTC [regression coefficients (β) (95% CI): 0.12 (0.09, 0.15) z-score; 3.1 (2.4, 3.8) mm and 0.5 (0.1, 0.7) mm, respectively]. The regression coefficients were highest for the middle tertile of WHZ gain with respect to HAZ and TL. Admission diarrhea and low plasma citrulline reduced the association between WHZ gain during ITC and HAZ and TL gain during OTC (P < 0.001). In contrast, pneumonia (P = 0.051) and elevated plasma C-reactive protein (P < 0.001) increased the association with TL gain, but reduced the association with KHL gain (P < 0.001).

CONCLUSIONS

Among children admitted with SAM, considerable WHZ gain during ITC was followed by very modest linear catch-up growth during OTC, with no indication of a WHZ gain threshold, above which linear growth was higher. To optimize linear growth in these children, early treatment of infections and conditions affecting the gut may be necessary.

Challenges in pediatric post-sepsis care in resource limited settings: a narrative review

OBJECTIVE

The objective of this narrative review is to outline the current epidemiology and interventional research within the context of sepsis recovery, and to provide a summary of key priorities for future work in this area.

BACKGROUND

Morbidity and mortality secondary to sepsis disproportionately affects children, especially those in low- and middle-income countries (LMICs), where over 85% of global cases and deaths occur. These regions are plagued by poorly resilient health systems, widespread socio-economic deprivation and unique vulnerabilities such as malnutrition. Reducing the overall burden of sepsis will require a multi-pronged strategy that addresses all three important periods along the sepsis care continuum - pre-facility, facility and post-facility. Of these aspects, post-facility issues have been largely neglected in research, practice and policy, and are thus the focus of this review.

METHODS

Relevant data for this review was identified through a literature search using PubMed, through a review of the citations of select systematic reviews and from the personal repositories of articles collected by the authors. Data is presented within three sections. The first two sections on the short and long-term outcomes among sepsis survivors each outline the epidemiology as well as review relevant interventional research done. Where clear gaps exist, these are stated. The third section focuses on priorities for future research. This section highlights the importance of data (and data systems) and of innovative interventional approaches, as key areas to improve research of post-sepsis outcomes in children.

CONCLUSIONS

During the initial post-facility period, mortality is high with as many children dying during this period as during the acute period of hospitalization, mostly due to recurrent illness (including infections) which are associated with malnutrition and severe acute disease. Long-term outcomes, often labelled as post-sepsis syndrome (PSS), are characterized by a lag in developmental milestones and suboptimal quality of life (QoL). While long-term outcomes have not been well characterized in resource limited settings, they are well described in high-income countries (HICs), and likely are important contributors to long-term morbidity in resource limited settings. The paucity of interventional research to improve post-discharge outcomes (short- or long-term) is a clear gap in addressing its burden. A focus on the development of improved data systems for collecting routine data, standardized definitions and terminology and a health-systems approach in research need to be prioritized during any efforts to improve outcomes during the post-sepsis phase.

Predicting the risk of mortality during hospitalization in sick severely malnourished children using daily evaluation of key clinical warning signs

BACKGROUND

Despite adherence to WHO guidelines, inpatient mortality among sick children admitted to hospital with complicated severe acute malnutrition (SAM) remains unacceptably high. Several studies have examined risk factors present at admission for mortality. However, risks may evolve during admission with medical and nutritional treatment or deterioration. Currently, no specific guidance exists for assessing daily treatment response. This study aimed to determine the prognostic value of monitoring clinical signs on a daily basis for assessing mortality risk during hospitalization in children with SAM.

METHODS

This is a secondary analysis of data from a randomized trial (NCT02246296) among 843 hospitalized children with SAM. Daily clinical signs were prospectively collected during ward rounds. Multivariable extended Cox regression using backward feature selection was performed to identify daily clinical warning signs (CWS) associated with time to death within the first 21 days of hospitalization. Predictive models were subsequently developed, and their prognostic performance evaluated using Harrell's concordance index (C-index) and time-dependent area under the curve (tAUC).

RESULTS

Inpatient case fatality ratio was 16.3% (n=127). The presence of the following CWS during daily assessment were found to be independent predictors of inpatient mortality: symptomatic hypoglycemia, reduced consciousness, chest indrawing, not able to complete feeds, nutritional edema, diarrhea, and fever. Daily risk scores computed using these 7 CWS together with MUAC<10.5cm at admission as additional CWS predict survival outcome of children with SAM with a C-index of 0.81 (95% CI 0.77-0.86). Moreover, counting signs among the top 5 CWS (reduced consciousness, symptomatic hypoglycemia, chest indrawing, not able to complete foods, and MUAC<10.5cm) provided a simpler tool with similar prognostic performance (C-index of 0.79; 95% CI 0.74-0.84). Having 1 or 2 of these CWS on any day during hospitalization was associated with a 3 or 11-fold increased mortality risk compared with no signs, respectively.

CONCLUSIONS

This study provides evidence for structured monitoring of daily CWS as recommended clinical practice as it improves prediction of inpatient mortality among sick children with complicated SAM. We propose a simple counting-tool to guide healthcare workers to assess treatment response for these children.

TRIAL REGISTRATION

NCT02246296.

Malnutrition, poor post-natal growth, intestinal dysbiosis and the developing lung

In extremely preterm infants, poor post-natal growth, intestinal dysbiosis and bronchopulmonary dysplasia are common, and each is associated with long-term complications. The central hypothesis that this review will address is that these three common conditions are interrelated. Challenges to studying this hypothesis include the understanding that malnutrition and poor post-natal growth are not synonymous and that there is not agreement on what constitutes a normal intestinal microbiota in this evolutionarily new population. If this hypothesis is supported, further study of whether "correcting" intestinal dysbiosis in extremely preterm infants reduces postnatal growth restriction and/or bronchopulmonary dysplasia is indicated.

Understanding the role of the gut in undernutrition: what can technology tell us?

Gut function remains largely underinvestigated in undernutrition, despite its critical role in essential nutrient digestion, absorption and assimilation. In areas of high enteropathogen burden, alterations in gut barrier function and subsequent inflammatory effects are observable but remain poorly characterised. Environmental enteropathy (EE)-a condition that affects both gut morphology and function and is characterised by blunted villi, inflammation and increased permeability-is thought to play a role in impaired linear growth (stunting) and severe acute malnutrition. However, the lack of tools to quantitatively characterise gut functional capacity has hampered both our understanding of gut pathogenesis in undernutrition and evaluation of gut-targeted therapies to accelerate nutritional recovery. Here we survey the technology landscape for potential solutions to improve assessment of gut function, focussing on devices that could be deployed at point-of-care in low-income and middle-income countries (LMICs). We assess the potential for technological innovation to assess gut morphology, function, barrier integrity and immune response in undernutrition, and highlight the approaches that are currently most suitable for deployment and development. This article focuses on EE and undernutrition in LMICs, but many of these technologies may also become useful in monitoring of other gut pathologies.

Clinical and Biochemical Markers of Risk in Uncomplicated Severe Acute Malnutrition

BACKGROUND AND OBJECTIVES

Use of mid-upper arm circumference (MUAC) as a single screening tool for severe acute malnutrition (SAM) assumes that children with a low weight-for-height z score (WHZ) and normal MUAC have lower risks of morbidity and mortality. However, the pathophysiology and functional severity associated with different anthropometric phenotypes of SAM have never been well characterized. We compared clinical characteristics, biochemical features, and health and nutrition histories of nonedematous children with SAM who had (1) low WHZ only, (2) both low WHZ and low MUAC, or (3) low MUAC only.

METHODS

In Bangladesh, Burkina Faso, and Liberia, we conducted a multicentric cohort study in uncomplicated, nonedematous children with SAM and low MUAC only (n = 161), low WHZ only (n = 138), or a combination of low MUAC and low WHZ (n = 152). Alongside routine anthropometric measurements, we collected a wide range of critical indicators of clinical and nutritional status and viability; these included serum leptin, an adipocytokine negatively associated with mortality risk in SAM.

RESULTS

Median leptin levels at diagnosis were lower in children with low WHZ only (215.8 pg/mL; P < .001) and in those with combined WHZ and MUAC deficits (180.1 pg/mL; P < .001) than in children with low MUAC only (331.50 pg/mL). The same pattern emerged on a wide range of clinical indicators, including signs of severe wasting, dehydration, serum ferritin levels, and caretaker-reported health deterioration, and was replicated across study sites.

CONCLUSIONS

Illustrative of the likely heterogeneous functional severity of the different anthropometric phenotypes of SAM, our results confirm the need to retain low WHZ as an independent diagnostic criterion.

Systemic inflammation is negatively associated with early post discharge growth following acute illness among severely malnourished children - a pilot study

Background: Rapid growth should occur among children with severe malnutrition (SM) with medical and nutritional management. Systemic inflammation (SI) is associated with death among children with SM and is negatively associated with linear growth. However, the relationship between SI and weight gain during therapeutic feeding following acute illness is unknown. We hypothesised that growth post-hospital discharge is associated with SI among children with SM. Methods: We conducted secondary analysis of data from HIV-uninfected children with SM (n=98) who survived and were not readmitted to hospital during one year of follow-up. We examined the relationship between changes in absolute deficits in weight and mid-upper-arm circumference (MUAC) from enrolment at stabilisation to 60 days and one year later, and untargeted plasma proteome, targeted cytokines/chemokines, leptin, and soluble CD14 using multivariate regularized linear regression. Results: The mean change in absolute deficit in weight and MUAC was -0.50kg (standard deviation; SD±0.69) and -1.20cm (SD±0.89), respectively, from enrolment to 60 days later. During the same period, mean weight and MUAC gain was 3.3g/kg/day (SD±2.4) and 0.22mm/day (SD±0.2), respectively. Enrolment interleukins; IL17-alpha and IL-2, and serum amyloid P were negatively associated with weight and MUAC gain during 60 days. Lipopolysaccharide binding protein and complement component 2 were negatively associated with weight gain only. Leptin was positively associated with weight gain. Soluble CD14, beta-2 microglobulin, and macrophage inflammatory protein 1 beta were negatively associated with MUAC gain only. Glutathione peroxidase 3 was positively associated with weight and MUAC gain during one year. Conclusions: Early post-hospital discharge weight and MUAC gain were rapid and comparable to children with uncomplicated SM treated in the community. Higher concentrations of SI markers were associated with less weight and MUAC gain, suggesting inflammation negatively impacts recovery from wasting. This finding warrants further research on reducing inflammation on growth among children with SM.

Risk factors for postdischarge mortality following hospitalization for severe acute malnutrition in Zimbabwe and Zambia

BACKGROUND

Children discharged from hospital following management of complicated severe acute malnutrition (SAM) have a high risk of mortality, especially HIV-positive children. Few studies have examined mortality in the antiretroviral therapy (ART) era.

OBJECTIVES

Our objectives were to ascertain 52-wk mortality in children discharged from hospital for management of complicated SAM, and to identify independent predictors of mortality.

METHODS

A prospective cohort study was conducted in children enrolled from 3 hospitals in Zambia and Zimbabwe between July 2016 and March 2018. The primary outcome was mortality at 52 wk. Univariable and multivariable Cox regression models were used to identify independent risk factors for death, and to investigate whether HIV modifies these associations.

RESULTS

Of 745 children, median age at enrolment was 17.4 mo (IQR: 12.8, 22.1 mo), 21.7% were HIV-positive, and 64.4% had edema. Seventy children (9.4%; 95% CI: 7.4, 11.7%) died and 26 exited during hospitalization; 649 were followed postdischarge. At discharge, 43.9% had ongoing SAM and only 50.8% of HIV-positive children were receiving ART. Vital status was ascertained for 604 (93.1%), of whom 55 (9.1%; 95% CI: 6.9, 11.7%) died at median 16.6 wk (IQR: 9.4, 21.9 wk). Overall, 20.0% (95% CI: 13.5, 27.9%) and 5.6% (95% CI: 3.8, 7.9%) of HIV-positive and HIV-negative children, respectively, died [adjusted hazard ratio (aHR): 3.83; 95% CI: 2.15, 6.82]. Additional independent risk factors for mortality were ongoing SAM (aHR: 2.28; 95% CI: 1.22, 4.25), cerebral palsy (aHR: 5.60; 95% CI: 2.72, 11.50) and nonedematous SAM (aHR: 2.23; 95% CI: 1.24, 4.01), with no evidence of interaction with HIV status.

CONCLUSIONS

HIV-positive children have an almost 4-fold higher mortality than HIV-negative children in the year following hospitalization for complicated SAM. A better understanding of causes of death, an improved continuum of care for HIV and SAM, and targeted interventions to improve convalescence are needed.

Relapse and post-discharge body composition of children treated for acute malnutrition using a simplified, combined protocol: A nested cohort from the ComPAS RCT

INTRODUCTION

Severe and moderate acute malnutrition (SAM and MAM) affect more than 50 million children worldwide yet 80% of these children do not access care. The Combined Protocol for Acute Malnutrition Study (ComPAS) trial assessed the effectiveness of a simplified, combined SAM/MAM protocol for children aged 6-59 months and found non-inferior recovery compared to standard care. To further inform policy, this study assessed post-discharge outcomes of children treated with this novel protocol in Kenya.

METHODS

Six 'combined' protocol clinics treated SAM and MAM children using an optimised mid-upper arm circumference (MUAC)-based dose of ready-to-use therapeutic food (RUTF). Six 'standard care' clinics treated SAM with weight-based RUTF rations; MAM with ready-to-use supplementary food (RUSF). Four months post-discharge, we assessed anthropometry, recent history of illness, and body composition by bioelectrical impedance analysis. Data was analysed using multivariable linear regression, adjusted for age, sex and allowing for clustering by clinic.

RESULTS

We sampled 850 children (median age 18 months, IQR 15-23); 44% of the original trial sample in Kenya. Children treated with the combined protocol had similar anthropometry, fat-free mass, fat mass, skinfold thickness z-scores, and frequency of common illnesses 4 months post-discharge compared the standard protocol. Mean subscapular skinfold z-scores were close to the global norm (standard care: 0.24; combined 0.27). There was no significant difference in odds of relapse between protocols (SAM, 3% vs 3%, OR = 1.0 p = 0.75; MAM, 10% vs 12%, OR = 0.90 p = 0.34).

CONCLUSIONS

Despite the lower dosage of RUTF for most SAM children in the combined protocol, their anthropometry and relapse rates at 4 months post-discharge were similar to standard care. MAM children treated with RUTF had similar body composition to those treated with RUSF and neither group exhibited excess adiposity. These results add further evidence that a combined protocol is as effective as standard care with no evidence of adverse effects post-discharge. A simplified, combined approach could treat more children, stretch existing resources further, and contribute to achieving Sustainable Development Goal Two.

Plasma calprotectin as a biomarker of mortality at antiretroviral treatment initiation in advanced HIV - pilot study

Background: In advanced HIV, significant mortality occurs soon after starting antiretroviral treatment (ART) in low- and middle-incomes countries. Calprotectin is a biomarker of innate response to infection and inflammatory conditions. We examined the association between plasma calprotectin collected before ART treatment and mortality among individuals with advanced HIV.   Methods: We conducted a pilot case-cohort study among HIV infected adults and adolescents over 13 years old with CD4+ <100/mm3 at ART initiation at two Kenyan sites. Participants received three factorial randomised interventions in addition to ART within the REALITY trial (ISRCTN43622374). Calprotectin collected at baseline (before ART) and after 4 weeks of treatment was measured in archived plasma of those who died within 24 weeks (cases) and randomly selected participants who survived (non-cases). Association with mortality was assessed using Cox proportional hazards models with inverse sampling probability weights and adjusted for age, sex, site, BMI, viral load, randomised treatments, and clustered by CD4+ count (0-24, 25-49, and 50-99 cells/mm3).   Results: Baseline median (IQR) plasma calprotectin was 6.82 (2.65-12.5) µg/ml in cases (n=39) and 5.01 (1.92-11.5) µg/ml in non-cases (n=58). Baseline calprotectin was associated with age, neutrophil count and the presence of cough, but not other measured indicators of infection. In adjusted multivariable models, baseline calprotectin was associated with subsequent mortality: HR 1.64 (95% CI 1.11 - 2.42) and HR 2.77 (95% CI 1.58 - 4.88) for deaths during the first twenty-four and four weeks respectively. Calprotectin levels fell between baseline and 4 weeks among both cases and non-cases irrespective of randomised interventions.   Conclusions: Among individuals with advanced HIV starting ART in Kenya, plasma calprotectin may have potential as a biomarker of early mortality. Validation in larger studies, comparison with other biomarkers and investigation of the sources of infection and inflammation are warranted.

Association of Serum Calprotectin Concentrations with Mortality in Critically Ill and Septic Patients

Background: Calprotectin is present in the cytosol of neutrophil granulocytes and released upon activation. Fecal calprotectin is applied in the clinical management of inflammatory bowel disease whereas serum calprotectin has been discussed as a biomarker in inflammatory disorders. However, its long-term prognostic relevance in critical illness remains unclear. Our aim was to investigate serum calprotectin concentrations as a prognostic biomarker in critically ill and septic patients. Methods: Serum calprotectin concentrations were analyzed in 165 critically ill patients (108 with sepsis, 57 without sepsis) included in our observational study. Patients were enrolled upon admission to the medical intensive care unit (ICU) of the RWTH Aachen University Hospital. Calprotectin concentrations were compared to 24 healthy controls and correlated with clinical parameters, therapeutic interventions, and survival. Results: Serum calprotectin concentrations were significantly increased in ICU patients as well as in septic patients compared to respective controls (p < 0.001 for ICU patients and p = 0.001 for septic patients). Lower calprotectin concentrations were measured in patients with comorbidities i.e., coronary artery disease. Calprotectin concentrations strongly correlated with the C-reactive protein (p < 0.001) and were closely associated to parameters of mechanical ventilation (i.a. inspiratory oxygen fraction, FiO2; p < 0.001). The overall survival was significantly impaired in septic patients with high baseline calprotectin concentrations (p = 0.036). However, patients with increasing calprotectin serum concentrations within the first week of ICU admission showed an improved overall survival (p = 0.009). Conclusions: In summary, serum calprotectin concentrations are significantly increased in critically ill patients with sepsis. High calprotectin concentrations at ICU admission predict long-term mortality risk, whereas increasing calprotectin concentrations are associated with a favorable long-term outcome.

Systemic inflammation is negatively associated with early post discharge growth following acute illness among severely malnourished children - a pilot study

Background: Rapid growth should occur among children with severe malnutrition (SM) when medically and nutritionally treated. Systemic inflammation (SI) is associated with death among children with SM and is negatively associated with linear growth. However, the relationship between SI and weight gain during therapeutic feeding following acute illness is unknown. We hypothesised that growth in the first 60 days post-hospital discharge is associated with SI among children with SM. Methods: We conducted secondary analysis of data from HIV-uninfected children with SM (n=98) who survived and were not readmitted to hospital during one year of follow up. We examined the relationship between changes in absolute deficits in weight and mid-upper-arm circumference (MUAC) from enrolment at stabilisation to 60 days later and untargeted plasma proteome, targeted cytokines/chemokines, leptin, and soluble CD14 (sCD14) using multivariate regularized linear regression. Results: The mean change in absolute deficit in weight and MUAC was -0.50kg (standard deviation; SD±0.69) and -1.20cm (SD±0.89), respectively, from enrolment to 60 days later. During the same period, mean weight and MUAC gain was 3.3g/kg/day (SD±2.4) and 0.22mm/day (SD±0.2), respectively. Enrolment inflammatory cytokines interleukin 17 alpha (IL17α), interleukin 2 (IL2), and serum amyloid P (SAP) were negatively associated with weight and MUAC gain. Lipopolysaccharide binding protein (LBP) and complement component 2 were negatively associated with weight gain only. Leptin was positively associated with weight gain. sCD14, beta-2 microglobulin (β2M), and macrophage inflammatory protein 1 beta (MIP1β) were negatively associated with MUAC gain only. Conclusions: Early post-hospital discharge weight and MUAC gain were rapid and comparable to children with uncomplicated SM treated with similar diet in the community. Higher concentrations of SI markers were associated with less weight and MUAC gain, suggesting inflammation negatively impacts recovery from wasting. This finding warrants further research on the role of inflammation on growth among children with SM.

Association between admission criteria and body composition among young children with moderate acute malnutrition, a cross-sectional study from Burkina Faso

Children with moderate acute malnutrition (MAM) are treated based on low weight-for-length z-score (WLZ), low mid-upper arm circumference (MUAC) or both. This study aimed to assess associations of admission criteria and body composition (BC), to improve treatment of MAM. We undertook a cross-sectional study among 6–23 months old Burkinabe children with MAM. Fat-free (FFM) and fat mass (FM) were determined by deuterium dilution and expressed as FFM (FFMI) and FM index (FMI). Of 1,489 children, 439 (29.5%) were recruited by low MUAC only (MUAC-O), 734 (49.3%) by low WLZ and low MUAC (WLZ-MUAC) and 316 (21.2%) by low WLZ only (WLZ-O). Thus, 1,173 (78.8%) were recruited by low MUAC, with or without low WLZ (ALL-MUAC). After adjustments, WLZ-O had 89 g (95% confidence interval (CI) 5; 172) lower FFM compared to MUAC-O. Similarly, WLZ-O had 0.89 kg/m² (95% CI 0.77; 1.01) lower FFMI compared to MUAC-O, whereas there was no difference for FMI. However, boys included by WLZ-O compared to MUAC-O had 0.21 kg/m² (95% CI 0.05; 0.38) higher FMI. In contrast, girls included by WLZ-O had 0.17 (95% CI 0.01; 0.33) kg/m² lower FMI compared to MUAC-O (interaction, p = 0.002). We found that different criteria for admission into MAM treatment programmes select children with differences in BC, especially FFMI.

Trial registration: ISRCTN42569496.

Plasma proteomics reveals markers of metabolic stress in HIV infected children with severe acute malnutrition

HIV infection affects up to 30% of children presenting with severe acute malnutrition (SAM) in Africa and is associated with increased mortality. Children with SAM are treated similarly regardless of HIV status, although mechanisms of nutritional recovery in HIV and/or SAM are not well understood. We performed a secondary analysis of a clinical trial and plasma proteomics data among children with complicated SAM in Kenya and Malawi. Compared to children with SAM without HIV (n = 113), HIV-infected children (n = 54) had evidence (false discovery rate (FDR) corrected p < 0.05) of metabolic stress, including enriched pathways related to inflammation and lipid metabolism. Moreover, we observed reduced plasma levels of zinc-α-2-glycoprotein, butyrylcholinesterase, and increased levels of complement C2 resembling findings in metabolic syndrome, diabetes and other non-communicable diseases. HIV was also associated (FDR corrected p < 0.05) with higher plasma levels of inflammatory chemokines. Considering evidence of biomarkers of metabolic stress, it is of potential concern that our current treatment strategy for SAM regardless of HIV status involves a high-fat therapeutic diet. The results of this study suggest a need for clinical trials of therapeutic foods that meet the specific metabolic needs of children with HIV and SAM.

Plasma calprotectin as a biomarker of mortality at antiretroviral treatment initiation in advanced HIV - pilot study

Background: In advanced HIV, significant mortality occurs soon after starting antiretroviral treatment (ART) in low- and middle-incomes countries. Calprotectin is a biomarker of innate response to infection and inflammatory conditions. We examined the association between plasma calprotectin at initiation of ART and mortality among individuals with advanced HIV. Methods: We conducted a pilot case-cohort study among HIV infected adults and children over 5 years old with CD4 + <100/mm 3 at ART initiation at two Kenyan sites. Participants received three factorial randomised interventions in addition to ART within the REALITY trial ( ISRCTN43622374). Calprotectin was measured by ELISA in archived plasma of those who died within 24 weeks (cases) and randomly selected participants who survived for 48 weeks (non-cases) for whom samples were available. Factors associated with baseline plasma calprotectin were investigated using linear regression. To test association with mortality, Cox proportional hazards models with inverse sampling probability weights and adjusted for age, sex, site, BMI, viral load, randomised treatments, and clustered by CD4 count were fitted. Results: Baseline median (IQR) plasma calprotectin was 6.82 (2.65-12.5) µg/ml in cases (n=39) and 5.01 (1.92-11.5) µg/ml in non-cases (n=58). Baseline calprotectin was associated with age, neutrophil count and the presence of cough, but not other measured indicators of infection. In adjusted multivariable models, baseline calprotectin was associated with subsequent mortality: HR 1.64 (95% CI 1.11 - 2.42) and HR 2.77 (95% CI 1.58 - 4.88) for deaths during the first twenty-four and four weeks respectively. Calprotectin levels fell between baseline and 4 weeks among both cases and non-cases irrespective of randomised interventions. Conclusion: Among individuals with advanced HIV starting ART in Kenya, plasma calprotectin may have potential as a biomarker of early mortality. Validation in larger studies, comparison with other biomarkers and investigation of the sources of infection and inflammation are warranted.

Body composition of children with moderate and severe undernutrition and after treatment: a narrative review

BACKGROUND

Until recently, undernourished children were usually assessed using simple anthropometric measurements, which provide global assessments of nutritional status. There is increasing interest in obtaining more direct data on body composition to assess the effects of undernutrition on fat-free mass (FFM) and its constituents, such as muscle and organs, and on fat mass (FM) and its regional distribution.

MAIN TEXT

Recent studies show that severe-acute undernutrition, categorised as 'wasting', is associated with major deficits in both FFM and FM that may persist in the long-term. Fat distribution appears more central, but this is more associated with the loss of peripheral fat than with the elevation of central fat. Chronic undernutrition, categorised as 'stunting', is associated with deficits in FFM and in specific components, such as organ size. However, the magnitude of these deficits is reduced, or - in some cases - disappears, after adjustment for height. This suggests that FFM is largely reduced in proportion to linear growth. Stunted children vary in their FM - in some cases remaining thin throughout childhood, but in other cases developing higher levels of FM. The causes of this heterogeneity remain unclear. Several different pathways may underlie longitudinal associations between early stunting and later body composition. Importantly, recent studies suggest that short children are not at risk of excess fat deposition in the short term when given nutritional supplementation.

CONCLUSION

The short- and long-term functional significance of FFM and FM for survival, physical capacity and non-communicable disease risk means that both tissues merit further attention in research on child undernutrition.

Current Understanding of Innate Immune Cell Dysfunction in Childhood Undernutrition

Undernutrition affects millions of children in low- and middle-income countries (LMIC) and underlies almost half of all deaths among children under 5 years old. The growth deficits that characterize childhood undernutrition (stunting and wasting) result from simultaneous underlying defects in multiple physiological processes, and current treatment regimens do not completely normalize these pathways. Most deaths among undernourished children are due to infections, indicating that their anti-pathogen immune responses are impaired. Defects in the body's first-line-of-defense against pathogens, the innate immune system, is a plausible yet understudied pathway that could contribute to this increased infection risk. In this review, we discuss the evidence for innate immune cell dysfunction from cohort studies of childhood undernutrition in LMIC, highlighting knowledge gaps in almost all innate immune cell types. We supplement these gaps with insights from relevant experimental models and make recommendations for how human and animal studies could be improved. A better understanding of innate immune function could inform future tractable immune-targeted interventions for childhood undernutrition to reduce mortality and improve long-term health, growth and development.