Impact of Childhood Malnutrition on Host Defense and Infection

Wasting and its associated factors among under-two years children in Ethiopia: a systematic review and meta-analysis

INTRODUCTION

Globally, about 45 million under-five children have suffered from wasting where Asian and African countries have the major share of these wasted children. Despite wasting is affected all types of populations, the long and short term effect is more severe and sensitive in under-two aged children. Hence, this review was intended to assess pooled prevalence and associated factors of wasting among under-two children in Ethiopia.

METHODS

The search was done using electronic data bases (Hinari, PubMed, Google scholar, Scopus) and research repositories from June 19-22/2023. The review included articles published between January 2013 and December 2023.The study included Cross-sectional/case control studies which report the prevalence and associated factors of wasting in under-two aged children. The quality of included studies was assessed using the Joanna Briggs Institute (JBI) quality assessment checklists for observational studies. The presence of heterogeneity between included studies was evaluated using Cochrane Q-test and the I2 statistics. Publication bias was checked through graphical and statistical test. Associated factors were estimated by random effect model using DerSimonian-Laird model weight.

RESULTS

The pooled prevalence of wasting among under-two children was 10.91% (95% CI: 8.97-12.85; I2 = 86.36%). Absence of maternal antenatal follow up (OR; 3.23: 95%CI: 1.20-5.26), no exclusive breast feeding until six months (OR; 5.30; 95%CI: 1.17-9.43), current illness of the child (OR; 2.58: 95%CI: 1.78-3.37), large family size (OR; 12.38; 95%CI: 1.37-26.13) and low wealth status of the households (OR; 3.91; 95%CI: 1. 54-8.36) were significant factors of wasting among under-two children.

CONCLUSIONS

This study disclosed that the pooled prevalence of wasting among under- two children were high in Ethiopia. Absence of maternal antenatal follow up, no exclusive breast feeding, low wealth status of the households, large family size and current illness of the child were significant factors of wasting. Strictly adherence of maternal antenatal follow up, counsel the parents to feed only breast milk until six months, limit the number of family size to the level of the household income and early treatment of the sick child were recommended. Furthermore, scale up the wealth status and living standard of the family can address the agenda of reducing and eradicating all forms of malnutrition. This review registered at PROSPERO with registration number CRD42023414914 ( https://www.crd.york.ac.uk/prospero/#myprospero ).

Controlling functional homeostasis of ileal resident macrophages by vitamin B12 during steady state and Salmonella infection in mice

Dietary micronutrients, particularly vitamin B12 (VB12), profoundly influence the physiological maintenance and function of intestinal cells. However, it is still unclear whether VB12 modulates the transcriptional and metabolic programming of ileal macrophages (iMacs), thereby contributing to intestinal homeostasis. Using multiomic approaches, we demonstrated that VB12 primarily supports the cell cycle activity and mitochondrial metabolism of iMacs, resulting in increased cell frequency compared to VB12 deficiency. VB12 also retained the ability to promote maintenance and metabolic regulation of iMacs during intestinal infection with Salmonella Typhimurium (STm). On the contrary, depletion of iMacs by inhibiting CSF1R signaling significantly increased host susceptibility to STm and prevented VB12-mediated pathogen reduction. These results thus suggest that regulation of VB12-dependent iMacs critically controls STm expansion, which may be of new relevance to advance our understanding of this vitamin and to strategically formulate sustainable therapeutic nutritional regimens that improve human gut health.

Effect of Oral Nutritional Supplementation on Health-Related Outcomes and Nutritional Biomarkers in Children and Adolescents with Undernutrition: A Systematic Review and Meta-Analysis

This systematic review aims to synthesize scientific evidence on the effects of oral nutritional supplementation (ONS) on health-related outcomes and nutritional biomarkers among children and adolescents with undernutrition. The review protocol was reported following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines. A comprehensive keyword and reference search was conducted in seven electronic bibliographic databases: PubMed, Academic Search Complete, Academic Search Premier, CINAHL, Global Health, Web of Science, and Scopus. We identified 14 peer-reviewed articles reporting results from 13 unique studies (eight randomized controlled trials, four pre-post studies, and one observational study). Study participants were recruited from 14 countries/regions, with ages ranging from 1 to 14 years. Outcomes of interest include health-related outcomes (acute diseases and infections) and nutritional biomarkers (e.g., serum iron and zinc). Six of the eight studies examining acute diseases/infections and five of the seven examining nutritional biomarkers reported statistically significant improvement in some, but not all, outcomes. A meta-analysis of three studies found that ONS interventions reduce the incidence of upper respiratory tract infection (URTI) by 39% (95% CI, 0.42-0.91) in children at nutritional risk when compared to dietary counseling (DC) alone. This systematic review suggests that ONS interventions can improve certain health-related outcomes and nutritional biomarkers in undernourished children and adolescents. Specifically, the use of ONS significantly reduces the risk of URTI, highlighting its potential to enhance immune function and break the cycle of undernutrition and infection.

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.

Development of a malnutrition model in mice: Comparative evaluation of food restriction percentage and different diets

Malnutrition is a complicated illness that affects people worldwide and is linked to higher death rates, a heightened vulnerability to infections, and delayed cognitive development. Experimental models have been constructed to comprehend the mechanisms associated with hunger. In this regard, the current study used two different types of food aiming to validate a murine model of malnutrition based on dietary restriction. The study was conducted with fifty-six Swiss male mice (eight-week-old) divided into eight groups (n=7 each) and fed the following experimental diets (10 weeks): Standard Diet (ST) ad libitum; ST 20% dietary restriction; ST 40% dietary restriction; ST 60% dietary restriction; AIN93-M diet ad libitum; AIN93-M 20% dietary restriction; AIN93-M 40% dietary restriction; AIN93-M 60% dietary restriction. Body, biochemical, and histological parameters were measured, and the restriction effects on genes related to oxidative stress (GPX1 and GPX4) in epididymal adipose tissue were evaluated. The results obtained showed that 20%, 40%, and 60% of dietary restrictions were able to reduce body weight when compared to controls, highlighting the accentuated weight loss in animals with 60% restrictions, especially those fed with AIN-93 M, which showed physical changes such as whitish skin and dull coat, voracious eating, and hunched posture. The present animal model also showed biochemical changes with hypoalbuminemia, as well as histological epididymal adipose tissue modulation. The presence of increased oxidative stress was observed when evaluating the GPX4 gene. Given the results, 60% food restriction using the AIN93-M diet was the best protocol for inducing malnutrition.

Hunger in the shadow of conflict: analyzing malnutrition and humanitarian challenges in Sudan

BACKGROUND

Conflict has become a global reality, particularly impacting millions of children, with the majority of conflicts occurring in developing nations, where 90% of the world's children reside. The Horn of Africa, especially Sudan, has faced severe conflicts, with the year 2023 witnessing one of the toughest conflicts in the region, resulting in a high number of internally displaced persons and refugees. Children, especially in areas like Darfur, Khartoum, Gezira, and Kordofan, bear the brunt of ongoing large-scale conflicts, facing widespread human rights violations and resource damage. Before the conflict that began in April 2023, Khartoum was home to numerous children's hospitals, but now only Elbuluk Hospital remains operational, facing a surge in admissions due to displacement and subsequent returns of civilians seeking medical care. Although malnutrition cases have increased, the case fatality rate associated with severe acute malnutrition has doubled from approximately 6% to 12% by March 2024, possibly due to uneven food distribution amid sporadic peace efforts.

RECOMMENDATIONS

Investing in grassroots organizations is crucial for facilitating effective humanitarian aid delivery, as they are uniquely positioned to identify and address local needs promptly and efficiently. Strengthening these organizations enhances their capacity to coordinate aid distribution and provide essential services tailored to regional conditions. Persistent violations of International Humanitarian Law (IHL) in conflict zones impede humanitarian efforts. Robust collaboration between international and local stakeholders is necessary to uphold and enforce IHL, with a focus on protecting civilian lives and ensuring safe, unhindered access for humanitarian aid while respecting the dignity of all affected individuals.

Quantifying the increased risk of illness in malnourished children: a global meta-analysis and propensity score matching approach

BACKGROUND

Childhood morbidity and mortality continue to be major public health challenges. Malnutrition increases the risk of morbidity and mortality from illnesses such as acute respiratory infections, diarrhoea, fever, and perinatal conditions in children. This study explored and estimated the magnitude of the associations between childhood malnutrition forms and child morbidity.

METHODS

We performed an individual participant data (IPD) meta-analysis and employed propensity score matching to examine crude (unadjusted) and adjusted associations. Our analysis utilized demographic and health datasets from surveys conducted between 2015 and 2020 in 27 low- and middle-income countries. Our objective was to quantify the risk of morbidity in malnourished children and estimate the population-attributable fraction (PAF) using a natural experimental design with a propensity score-matched cohort.

RESULTS

The IPD meta-analysis of child morbidity across three childhood malnutrition forms presented nuanced results. Children with double-burden malnutrition had a 5% greater risk of morbidity, which was not statistically significant. In contrast, wasted children had a 28% greater risk of morbidity. Overweight children exhibited a 29% lower risk of morbidity. Using the matched sample, children with double-burden malnutrition and overweight children had lower morbidity risks (1.7%, RR: 0.983 (95% CI, 0.95 to 1.02) and 20%, RR: 0.80 (95% CI, 0.76 to 0.85), respectively), while wasting was associated with a 1.1 times (RR: 1.094 (95% CI, 1.05 to 1.14)) greater risk of morbidity. Eliminating double-burden malnutrition and wasting in the four and seven countries with significant positive risk differences could reduce the child morbidity burden by an estimated average of 2.8% and 3.7%, respectively.

CONCLUSIONS

Our study revealed a correlation between specific childhood malnutrition subtypes-double-burden malnutrition and wasting-and increased risks of morbidity. Conversely, overweight children exhibited a lower risk of immediate morbidity, yet they may face potential long-term health challenges, indicating the necessity for nuanced approaches to childhood nutrition.

Maternal Feeding Practices of Children One to Three Years in Collins Chabane Municipality of South Africa

The aim was to assess maternal feeding practices of children one to three years. A descriptive observational design was employed. The sample consisted of mothers-child dyads. A validated structured questionnaire was used. Data was analyzed using SPSS version 26.0. The nutrition status of the children at birth indicated 11.6% underweight as compared to the time of the study (7.2%), 7.9% were stunted increased to 38.0%, while wasting decreased from 11.4%-2.4%. Early cessation of breastfeeding and inappropriate complementary feeding practices were the factors influencing growth. The prevalence of underweight and wasting were low while stunting and overweight were high.

Effect of high-calorie formula on weight, height increment, IGF-1 and TLC in growth faltering children: A quasi-experimental study

High-calorie formulas have been used to promote catch-up growth in undernourished children. The level of insulin-like growth factor 1 (IGF-1) is closely related to weight and nutritional intake, whereas low a total lymphocyte count (TLC) is associated with impaired immune system function in undernourished children. This study was conducted to investigate the effect of high-calorie formula as an intervention on weight, height increment, IGF-1 and TLC in children with growth faltering or undernutrition. A quasi-experimental study with pre- and post-design was conducted in the outpatient clinic of a private hospital during October 2021-July 2022 on children with growth failure and underlying infection. For 90 days, subjects were given a high-calorie formula. An enzyme-linked immunosorbent assay was then conducted to measure IGF-1, followed by a complete blood count examination. Subjects were divided into two groups based on age: Group 1 (12-24 months) and Group 2 (>24-60 months). There was a significant increment in body weight and body length/height after intervention but no significant difference between the groups. The increment of body length/height after intervention was greater in Group 1 than Group 2 (p = 0.000) and reduced the incidence of stunted/severely stunted and wasted/severely wasted children (p > 0.05). IGF-1 increased after the intervention but with no significant difference (1.42 ± 8.31 ng/ml; p = 0.144). There was a significant reduction in TLC after the intervention (1194.34 + 4400.34 cells/mm3; p = 0.002) that was reduced in Group 1 and slightly increased in Group 2 (p = 0.003). Being underweight/severely underweight increased the risk of a low TLC by 27.658-fold but this risk was reduced by 25.904-fold after nutritional intervention. High-calorie formula intervention increases body weight and body length/height, reduces the incidence of underweight, stunted and wasted children and improves IGF-1 levels.

Rag-GTPase-TFEB/TFE3 axis controls B cell mitochondrial fitness and humoral immunity independent of mTORC1

During the humoral immune response, B cells undergo rapid metabolic reprogramming with a high demand for nutrients, which are vital to sustain the formation of the germinal centers (GCs). Rag-GTPases sense amino acid availability to modulate the mechanistic target of rapamycin complex 1 (mTORC1) pathway and suppress transcription factor EB (TFEB) and transcription factor enhancer 3 (TFE3), members of the microphthalmia (MiT/TFE) family of HLH-leucine zipper transcription factors. However, how Rag-GTPases coordinate amino acid sensing, mTORC1 activation, and TFEB/TFE3 activity in humoral immunity remains undefined. Here, we show that B cell-intrinsic Rag-GTPases are critical for the development and activation of B cells. RagA/RagB deficient B cells fail to form GCs, produce antibodies, and generate plasmablasts in both T-dependent (TD) and T-independent (TI) humoral immune responses. Deletion of RagA/RagB in GC B cells leads to abnormal dark zone (DZ) to light zone (LZ) ratio and reduced affinity maturation. Mechanistically, the Rag-GTPase complex constrains TFEB/TFE3 activity to prevent mitophagy dysregulation and maintain mitochondrial fitness in B cells, which are independent of canonical mTORC1 activation. TFEB/TFE3 deletion restores B cell development, GC formation in Peyer's patches and TI humoral immunity, but not TD humoral immunity in the absence of Rag-GTPases. Collectively, our data establish Rag-GTPase-TFEB/TFE3 axis as an mTORC1 independent mechanism to coordinating nutrient sensing and mitochondrial metabolism in B cells.

Predictors of severity and prolonged hospital stay of viral acute respiratory infections (ARI) among children under five years in Burkina Faso, 2016-2019

BACKGROUND

Viruses are the leading etiology of acute respiratory infections (ARI) in children. However, there is limited knowledge on drivers of severe acute respiratory infection (SARI) cases involving viruses. We aimed to identify factors associated with severity and prolonged hospitalization of viral SARI among children < 5 years in Burkina Faso.

METHODS

Data were collected from four SARI sentinel surveillance sites during October 2016 through April 2019. A SARI case was a child < 5 years with an acute respiratory infection with history of fever or measured fever ≥ 38 °C and cough with onset within the last ten days, requiring hospitalization. Very severe ARI cases required intensive care or had at least one danger sign. Oropharyngeal/nasopharyngeal specimens were collected and analyzed by multiplex real-time reverse-transcription polymerase chain reaction (rRT-PCR) using FTD-33 Kit. For this analysis, we included only SARI cases with rRT-PCR positive test results for at least one respiratory virus. We used simple and multilevel logistic regression models to assess factors associated with very severe viral ARI and viral SARI with prolonged hospitalization.

RESULTS

Overall, 1159 viral SARI cases were included in the analysis after excluding exclusively bacterial SARI cases (n = 273)very severe viral ARI cases were common among children living in urban areas (AdjOR = 1.3; 95% CI: 1.1-1.6), those < 3 months old (AdjOR = 1.5; 95% CI: 1.1-2.3), and those coinfected with Klebsiella pneumoniae (AdjOR = 1.9; 95% CI: 1.2-2.2). Malnutrition (AdjOR = 2.2; 95% CI: 1.1-4.2), hospitalization during the rainy season (AdjOR = 1.71; 95% CI: 1.2-2.5), and infection with human CoronavirusOC43 (AdjOR = 3; 95% CI: 1.2-8) were significantly associated with prolonged length of hospital stay (> 7 days).

CONCLUSION

Younger age, malnutrition, codetection of Klebsiella pneumoniae, and illness during the rainy season were associated with very severe cases and prolonged hospitalization of SARI involving viruses in children under five years. These findings emphasize the need for preventive actions targeting these factors in young children.

The nutrient-sensing Rag-GTPase complex in B cells controls humoral immunity via TFEB/TFE3-dependent mitochondrial fitness

During the humoral immune response, B cells undergo rapid metabolic reprogramming with a high demand for nutrients, which are vital to sustain the formation of the germinal centers (GCs). Rag-GTPases sense amino acid availability to modulate the mechanistic target of rapamycin complex 1 (mTORC1) pathway and suppress transcription factor EB (TFEB) and transcription factor enhancer 3 (TFE3), members of the microphthalmia (MiT/TFE) family of HLH-leucine zipper transcription factors. However, how Rag-GTPases coordinate amino acid sensing, mTORC1 activation, and TFEB/TFE3 activity in humoral immunity remains undefined. Here, we show that B cell-intrinsic Rag-GTPases are critical for the development and activation of B cells. RagA/RagB deficient B cells fail to form GCs, produce antibodies, and generate plasmablasts in both T-dependent (TD) and T-independent (TI) humoral immune responses. Deletion of RagA/RagB in GC B cells leads to abnormal dark zone (DZ) to light zone (LZ) ratio and reduced affinity maturation. Mechanistically, the Rag-GTPase complex constrains TFEB/TFE3 activity to prevent mitophagy dysregulation and maintain mitochondrial fitness in B cells, which are independent of canonical mTORC1 activation. TFEB/TFE3 deletion restores B cell development, GC formation in Peyer's patches and TI humoral immunity, but not TD humoral immunity in the absence of Rag-GTPases. Collectively, our data establish Rag-GTPase-TFEB/TFE3 pathway as an mTORC1 independent mechanism to coordinating nutrient sensing and mitochondrial metabolism in B cells.

Addressing global health disparities in the management of RSV infection in infants and children: Strategies for preventing bronchiolitis and post-bronchiolitis recurrent wheezing

Background: The topic of equitable access to health care and its impact on exacerbating worldwide inequities in child health not only strikes at the heart of our health-care delivery systems but also deeply resonates with our collective social consciences. Nowhere is this better seen on a global scale than in the burden of illness caused by respiratory syncytial virus (RSV) infection, which extracts the most severe morbidity and mortality in infants and children in low- and middle-income countries (LMIC). This report addresses global health disparities that exist in the management of RSV infection in infants and children, and offers strategies for preventing bronchiolitis and postbronchiolitis recurrent wheezing in LMICs. Methods: A systematic literature review was conducted across the PubMed data bases of RSV infection and the socioeconomic impact of bronchiolitis and postbronchiolitis recurrent wheezing in LMICs. Results: The results of the present study address the many issues that deal with the question if prevention of RSV bronchiolitis can mitigate recurrent wheezing episodes and links RSV risks, downstream effects, prevention, malnutrition, and socioeconomic restraints of developing countries with a call for possible global action. Conclusion: The present study stresses the importance of considering the linkage between malnutrition and disease susceptibility because of the known relationships between undernutrition and greater vulnerability to infectious diseases, including RSV infection. These complex interactions between infectious disease and undernutrition also raise issues on the longer-term sequelae of postbronchiolitis recurrent wheezing. This prompts a discussion on whether industrialized countries should prioritize the provision of newly developed monoclonal antibodies and RSV vaccines to LMICs or whether vital nutritional needs should be a first focus. The resolution of these issues will require research and greater international discourse.

Induction of cervical disc degeneration and discogenic pain by low concentration Propionibacterium acnes infection: an in vivo animal study

BACKGROUND

Although cervical intervertebral disc (IVD) degeneration is closely associated with neck pain, its cause remains unclear. In this study, an animal model of cervical disc degeneration and discogenic neck pain induced by a low concentration of Propionibacterium acnes (P. acnes-L) is investigated to explore the possible mechanisms of cervical discogenic pain.

METHODS

Cervical IVD degeneration and discitis was induced in 8-week-old male rats in C3-C6 IVDs through the anterior intervertebral puncture with intradiscal injections of low and high concentrations of P. acnes (P. acnes-L, n = 20 and P. acnes-H, n = 15) or Staphylococcus aureus (S. aureus, n = 15), compared to control (injection with PBS, n = 20). The structural changes in the cervical IVD using micro-CT, histological evaluation, and gene expression assays after MRI scans at 2 and 6 weeks post-modeling. The P. acnes-L induced IVD degeneration model was assessed for cervical spine MRI, histological degeneration, pain-like behaviors (guarding behavior and forepaw von Frey), nerve fiber growth in the IVD endplate region, and DRG TNF-α and CGRP.

RESULTS

IVD injection with P. acnes-L induced IVD degeneration with decreased IVD height and MRI T2 values. IVD injection with P. acnes-H and S. aureus both lead to discitis-like changes on T2-weighted MRI, trabecular bone remodeling on micro-CT, and osseous fusion after damage in the cartilage endplate adjacent to the injected IVD. Eventually, rats in the P. acnes-L group exhibited significant nociceptive hypersensitivity, nerve fiber ingrowth was observed in the IVD endplate region, inflammatory activity in the DRG was significantly increased compared to the control group, and the expression of the pain neurotransmitter CGRP was significantly upregulated.

CONCLUSION

P. acnes-L was validated to induce cervical IVD degeneration and discogenic pain phenotype, while P. acnes-H induced was identified to resemble septic discitis comparable to those caused by S. aureus infection.

Factors Contributing to Malnutrition among Children Under 5 Years at St. Elizabeth Catholic Hospital, Ahafo Hwidiem

Background

Nutrition among children under 5 plays an important role in the overall development of children physically and psychologically. Nutritional deficiencies and malnutrition generally affect children. In this study, we estimate the prevalence of 3 malnutrition indicators underweight, stunting and wasting and to assess factors associated with them.

Objective

The main objective of the study was to assess the factors contributing to malnutrition among children under 5 years old.

Design

The study employed a descriptive cross-sectional study design to assess the factors contributing to malnutrition among children under 5 years of age.

Methods

This is quantitative cross-sectional facility-based study of 245 children aged 11 to 49 months. A structured questionnaire was used, and anthropometric measurements were taken to collect data. The Pearson chi-square test was used to assess the bivariate association between the outcomes and the characteristics. The binary logistic regression model was employed to estimate the crude and adjusted odds of malnutrition indicators among the characteristics observed in the study.

Results

The prevalence of underweight, stunting, and wasting were 35.9, 13.9, and 33.9%, respectively. Underweight was significantly higher among females compared to males (42.0% vs. 24.1%) and highest among children aged 11 to 23 months (53.6%). Female children had 3 times more odds of being underweight (AOR: 3.09, 95% CI: 1.56-6.12). Compared to children aged 11 to 23 months, the odds of being underweight were less among children aged 24 to 35 months (AOR: 0.26, 95% CI: 0.13-0.51, P < .001), and 36 to 47 months (AOR: 0.9, 95% CI: 0.03-0.29, P < .001). Wasting was less prevalent among children aged 11 to 23 months (4.8%). Also, wasting was high among children aged 24 to 35 months (AOR: 27.41, 95% CI: 9.12-82.37, P < .001), 36 to 47 months (AOR: 28.23, 95% CI: 7.59-104.94, P < .001), and 48 to 59 months (AOR: 18.10, 95% CI: 3.04-107.76, P < .001). None of the observed factors were associated with stunting in the study.

Conclusion

This study concludes that child malnutrition was high among under-five children. Promoting the use of healthy complementary feeding, preventing diarrheal diseases, and vaccinating children integrated with access to nutrition education programs are vital interventions to improve the nutritional status of children.

A metabolic perspective of the neutrophil life cycle: new avenues in immunometabolism

Neutrophils are the most abundant innate immune cells. Multiple mechanisms allow them to engage a wide range of metabolic pathways for biosynthesis and bioenergetics for mediating biological processes such as development in the bone marrow and antimicrobial activity such as ROS production and NET formation, inflammation and tissue repair. We first discuss recent work on neutrophil development and functions and the metabolic processes to regulate granulopoiesis, neutrophil migration and trafficking as well as effector functions. We then discuss metabolic syndromes with impaired neutrophil functions that are influenced by genetic and environmental factors of nutrient availability and usage. Here, we particularly focus on the role of specific macronutrients, such as glucose, fatty acids, and protein, as well as micronutrients such as vitamin B3, in regulating neutrophil biology and how this regulation impacts host health. A special section of this review primarily discusses that the ways nutrient deficiencies could impact neutrophil biology and increase infection susceptibility. We emphasize biochemical approaches to explore neutrophil metabolism in relation to development and functions. Lastly, we discuss opportunities and challenges to neutrophil-centered therapeutic approaches in immune-driven diseases and highlight unanswered questions to guide future discoveries.

Effect of Gut Microbiota-Directed Complementary Food Supplementation on Fecal and Plasma Biomarkers of Gut Health and Environmental Enteric Dysfunction in Slum-Dwelling Children with Moderate Acute Malnutrition

Dietary supplementation with a gut microbiota-directed complementary food (MDCF-2) significantly improved weight gain and repaired gut microbiota, as reported in a recent randomized controlled trial on Bangladeshi children with moderate acute malnutrition (MAM). Environmental enteric dysfunction (EED) is a small bowel disorder, and recent evidence shows that it is linked to growth failure in children. Therefore, we intended to investigate whether supplementation with MDCF-2 has any role in modifying gut health by changing the levels of biomarkers of EED and gut inflammation in children with MAM. We randomly assigned 124 children aged 12-18 months to one of two intervention diets, either MDCF-2 or ready-to-use supplementary food (RUSF). Approximately 50 g of the diet was administered in two feeding sessions daily for 12 weeks. Stool and plasma biomarkers were assessed to evaluate intestinal health. Results showed that the average change in citrulline concentration (µmol/L) significantly increased among children who consumed MDCF-2 compared to those who consumed RUSF (mean difference-in-differences: 123.10; 95% CI: 3.60, 242.61; p = 0.044). The research findings demonstrated that MDCF-2 might have a beneficial effect on improving the gastrointestinal health of malnourished children.

Clinical Significance of the Preoperative Inflammatory Burden Index in Esophageal Cancer

INTRODUCTION

The inflammatory burden index (IBI) serves as a prognostic marker for several cancers. Here, we evaluated the predictive value of preoperative IBI associated with the surgical and oncological outcomes of patients with esophageal cancer (EC).

METHODS

The IBI was formulated as C-reactive protein × neutrophil/lymphocyte. We retrospectively analyzed preoperative IBI of 147 EC patients receiving esophagectomy between 2008 and 2018. Cox proportional hazards models and multivariable logistic regression were employed to identify independent risk factors of surgical site infection and prognosis.

RESULTS

Increased preoperative IBI significantly correlated with higher tumor stage. Patients with high IBI experienced shorter overall survival (p = 0.0002) and disease-free survival (p = 0.002) compared with those with low IBI. In the adjusted Cox proportional hazards regression models, increased IBI served as an independent prognostic factor for overall survival (hazard ratio, 3.56; 95% confidence interval, 1.79-7.34; p = 0.0003) and disease-free survival (hazard ratio, 3.03; 95% confidence interval, 1.60-5.92; p = 0.007). Multivariable analysis identified preoperative high IBI which served as an independent risk factor for overall surgical site infection (odds ratio, 2.53; 95% confidence interval, 1.00-6.38; p = 0.049).

CONCLUSION

Preoperative IBI may serve as a useful predictor of prognosis and surgical site infection of patients with EC after esophagectomy.

Association between nutritional status and biochemical markers among hematopoietic stem cell transplant candidates: a cross-sectional study

AIM

Candidates of Hematopoietic Stem Cell Transplantation (HSCT) may be at nutritional risk due to decreased oral intake, high nutritional requirements and nutrient malabsorption. The aim of this study was to evaluate the association between nutritional status and blood biomarkers in candidates of HSCT.

METHODS

A total of 278 patients aged 18-65 years old were recruited and their baseline demographic and clinical characteristics were recorded. All subjects underwent nutritional status analysis using Nutritional Risk Screening (NRS-2002). Blood biomarkers including C-reactive protein (CRP), Erythrocyte Sedimentation Rate (ESR), hemoglobin, albumin and total protein as well as CRP-albumin ratio (CAR) and Body Mass Index (BMI) were measured and compared between two groups based on Nutritional Risk Screening (NRS-2002) within 24 h of admission in Bone Marrow Transplant ward.

RESULTS

The results showed that undernourished patients (NRS ≥ 3) had significantly higher inflammatory markers including ESR, CRP and CAR as well as lower BMI and serum albumin and hemoglobin concentrations (P < 0.05); however, no significant association was observed in terms of total protein even after adjusting for confounders (P > 0.05).

CONCLUSIONS

This study revealed that BMI combined with biochemical markers are the appropriate parameters for assessment of nutritional status in HSCT candidates. Furthermore, the nutritional status was verified to be significantly associated with systematic inflammation.

A foundational approach to culture and analyze malnourished organoids

The gastrointestinal (GI) epithelium plays a major role in nutrient absorption, barrier formation, and innate immunity. The development of organoid-based methodology has significantly impacted the study of the GI epithelium, particularly in the fields of mucosal biology, immunity, and host-microbe interactions. Various effects on the GI epithelium, such as genetics and nutrition, impact patients and alter disease states. Thus, incorporating these effects into organoid-based models will facilitate a better understanding of disease progression and offer opportunities to evaluate therapeutic candidates. One condition that has a significant effect on the GI epithelium is malnutrition, and studying the mechanistic impacts of malnutrition would enhance our understanding of several pathologies. Therefore, the goal of this study was to begin to develop methodology to generate viable malnourished organoids with accessible techniques and resources that can be used for a wide array of mechanistic studies. By selectively limiting distinct macronutrient components of organoid media, we were able to successfully culture and evaluate malnourished organoids. Genetic and protein-based analyses were used to validate the approach and confirm the presence of known biomarkers of malnutrition. Additionally, as proof-of-concept, we utilized malnourished organoid-derived monolayers to evaluate the effect of malnourishment on barrier formation and the ability of the bacterial pathogen Shigella flexneri to infect the GI epithelium. This work serves as the basis for new and exciting techniques to alter the nutritional state of organoids and investigate the related impacts on the GI epithelium.

The Tolerance Model of Non-Inflammatory Immune Competence in Acute Pediatric Malnutrition: Origins, Evidence, Test of Fitness and Growth Potential

The tolerance model rests on the thesis of a physiologically regulated, albeit unsustainable, systemic attempt to adapt to the catabolic challenge posed by acute prepubescent malnutrition even in its severe forms. The model centers on the immunological component of the attempt, positing reorientation toward a non-inflammatory form of competence in place of the classic paradigm of immunological attrition and exhaustion. The foundation of the model was laid in 1990, and sixteen years later it was articulated formally on the basis of a body of evidence centered on T cell cytokines and interventions with cytokine and hormonal mediators. The benefit originally suggested was a reduced risk of autoimmune pathologies consequent to the catabolic release of self-antigens, hence the designation highlighting immune tolerance. Herein, the emergence of the tolerance model is traced from its roots in the recognition that acute malnutrition elicits an endocrine-based systemic adaptive attempt. Thereafter, the growth of the evidence base supporting the model is outlined, and its potential to shed new light on existing information is tested by application to the findings of a published clinical study of acutely malnourished children. Finally, some knowledge gaps pertinent to the model are identified and its potential for growth consonant with evolving perceptions of immunobiology is illustrated.

Increase in Incidence Rates and Risk Factors for Multidrug Resistant Bacteria in Septic Children: A Nationwide Spanish Cohort Study (2013-2019)

The emergence of multidrug-resistant (MDR) bacteria in children is a growing concern, particularly among septic patients, given the need for first-right dosing. Our aim was to determine the incidence rates and factors associated with MDR-sepsis in the pediatric intensive care unit (PICU), using data from the Spanish ENVIN-HELICS PICU registry between 2013 and 2019. The rate of MDR bacteria among septic children ranged between 5.8 and 16.2% throughout this study period, with a significant increase since 2015 (p = 0.013). MDR-gram-negative bacteria (92%), particularly EBL-Enterobacterales (63.7%), were the most frequent causative microorganisms of MDR-sepsis. During this study period, sixteen MDR-sepsis (32.6%) corresponded to intrahospital infections, and 33 (67.4%) had community-onset sepsis, accounting for 10.5% of the overall community-onset sepsis. Independent risk factors associated with MDR-sepsis were antibiotics 48 h prior to PICU admission (OR 2.38) and PICU onset of sepsis (OR 2.58) in >1 year-old children, and previous malnourishment (OR 4.99) in <1 year-old children. Conclusions: There was an alarming increase in MDR among septic children in Spain, mainly by gram-negative (ESBL-Enterobacterales), mostly coming from the community setting. Malnourished infants and children on antibiotics 48 h prior to PICU are at increased risk and therefore require closer surveillance.

The Neutrophil-to-Lymphocyte Ratio (NLR) Can Predict Sepsis's Presence and Severity in Malnourished Infants-A Single Center Experience

Sepsis represents one of the leading causes of death in newborns and infants, and prompt diagnosis is essential for achieving favorable outcomes. Regarding malnourished children with concurrent infection, most studies have focused, besides blood culture, on C-reactive protein and procalcitonin. Because malnutrition has a deleterious effect on cellular immune competence, the present study characterized the acute-phase response, including hematological indices, in response to sepsis. Among the examined laboratory biomarkers, procalcitonin and neutrophil-to-lymphocyte ratio were the most accurate discriminators between sepsis patients and those with bacterial infection. Moreover, these two parameters showed a gradual increase between sepsis, severe sepsis, and septic shock patients (p < 0.001). Subgroup analysis of the sepsis group revealed positive correlations of NLR with prolonged ICU stay (<0.001), acute organ dysfunction (0.038), mechanical ventilation (<0.001), and fatality (<0.001). In summary, our results suggest that the neutrophil-to-lymphocyte ratio can be used as an auxiliary diagnostic index in discriminating the presence and severity of bacterial sepsis in malnourished infants.

More Than Three Years for Normalisation of Routine Laboratory Values after Gluten Withdrawal in Paediatric Coeliac Patients

The assessment of the nutritional and inflammatory status of paediatric patients with coeliac disease is an interesting approach to early diagnosis and functional follow-up. Most authors agree that the normalisation of symptoms takes about one year. The aim of the study was to evaluate the clinical manifestation and normalisation of routine analytics in Spanish children diagnosed with celiac disease.

METHODS

We performed a retrospective case-control study in Spanish paediatric patients, including 21 celiac patients and 20 healthy controls. The 21 patients selected in the case-control study were followed for 5 years after starting a gluten-free diet (GFD). All patients had type 3 villous atrophy according to the Marsh-Oberhuber classification. A total of 39 blood samples were taken before the start of the GFD, and 109 were taken after. Twenty control sera from healthy donors were used for comparison.

RESULTS

We found that patients had a subclinical but statistically significant increase in blood calcium, transaminases, and white blood cells, and a decrease in serum iron, at the time of diagnosis. Our study also shows that analytical values normalise within five years on a gluten-free diet.

CONCLUSIONS

The use of a combination of subclinical changes, including low iron, high calcium, elevated leukocytes, lymphocytes, and ALT levels in blood samples, together with a low growth percentile, is pertinent in detecting coeliac disease. This set of parameters could help in the diagnosis of patients without clinical symptoms. We can also show that the levels of Fe, Ca, transaminases, and leucocytes remain subclinically altered after 3 years, despite the gluten-free diet.

Burden of lower respiratory infections and associated risk factors across regions in Ethiopia: a subnational analysis of the Global Burden of Diseases 2019 study

OBJECTIVE

This analysis is to present the burden and trends of morbidity and mortality due to lower respiratory infections (LRIs), their contributing risk factors, and the disparity across administrative regions and cities from 1990 to 2019.

DESIGN

This analysis used Global Burden of Disease 2019 framework to estimate morbidity and mortality outcomes of LRI and its contributing risk factors. The Global Burden of Disease study uses all available data sources and Cause of Death Ensemble model to estimate deaths from LRI and a meta-regression disease modelling technique to estimate LRI non-fatal outcomes with 95% uncertainty intervals (UI).

STUDY SETTING

The study includes nine region states and two chartered cities of Ethiopia.

OUTCOME MEASURES

We calculated incidence, death and years of life lost (YLLs) due to LRIs and contributing risk factors using all accessible data sources. We calculated 95% UIs for the point estimates.

RESULTS

In 2019, LRIs incidence, death and YLLs among all age groups were 8313.7 (95% UI 7757.6-8918), 59.4 (95% UI 49.8-71.4) and 2404.5 (95% UI 2059.4-2833.3) per 100 000 people, respectively. From 1990, the corresponding decline rates were 39%, 61% and 76%, respectively. Children under the age of 5 years account for 20% of episodes, 42% of mortalities and 70% of the YLL of the total burden of LRIs in 2019. The mortality rate was significantly higher in predominantly pastoralist regions-Benishangul-Gumuz 101.8 (95% UI 84.0-121.7) and Afar 103.7 (95% UI 86.6-122.6). The Somali region showed the least decline in mortality rates. More than three-fourths of under-5 child deaths due to LRIs were attributed to malnutrition. Household air pollution from solid fuel attributed to nearly half of the risk factors for all age mortalities due to LRIs in the country.

CONCLUSION

In Ethiopia, LRIs have reduced significantly across the regions over the years (except in elders), however, are still the third-leading cause of mortality, disproportionately affecting children younger than 5 years old and predominantly pastoralist regions. Interventions need to consider leading risk factors, targeted age groups and pastoralist and cross-border communities.

What Came First: Malnutrition or Severe Disease?

A 20-year-old female with depression presented to the emergency department with chronic weight loss, weakness, fatigue, hair loss, rash, palpitations, and 2 weeks of cough. Initial history revealed that she had disordered eating habits with dietary restriction, experienced a 50-pound unintentional weight loss over 2 years despite reported adherence to nutritional supplementation, and had a normal gastrointestinal workup. On examination, she was markedly cachectic with a BMI of 10.3kg/m2 and hypotensive (84/69 mmHg). Her cardiovascular examination revealed a regular rate and rhythm without a murmur. Her breath sounds were diminished in the upper lobes bilaterally. A skin examination showed diffuse hair loss, skin breakdown, and peeling with a tender, erythematous, papular rash over the bilateral ankles, and nonpitting edema. A chest radiograph showed a right upper lobe opacity and lucent lesions in the left proximal humerus. A focused assessment with sonography for trauma examination showed a large pericardial effusion. Chest computed tomography revealed a right upper lobe opacity with an associated cavitation. Though she began improving with rifampin, isoniazid, pyrazinamide, ethambutol, levofloxacin, azithromycin, and nutritional rehabilitation, her clinical course was complicated by an acute worsening nearly 1 month into her hospitalization with persistent high fevers, worsening cough, development of a murmur, and worsening consolidation on chest computed tomography. Adolescent Medicine, Infectious Diseases, Gastroenterology, and Allergy and Immunology were consulted to guide the diagnostic evaluation and management of this patient's complex clinical course.

Concurrent wasting and stunting among marginalised children in Sana'a city, Yemen: a cross-sectional study

Concurrent wasting and stunting (WaSt) is a serious form of malnutrition among young children, particularly vulnerable groups affected by the conflict. Understanding the prevalence and risk factors of WaSt among vulnerable children is important to develop effective intervention measures to reduce the burden of WaSt. The present study aimed to identify the prevalence of and risk factors for WaSt among marginalised children aged 6-59 months in Sana'a city, Yemen. A community-based cross-sectional design was conducted on a total sample size of 450 marginalised children aged 6-59 months who lived at home with their mothers. Multivariable logistic regression analysis was performed and the prevalence of WaSt was found to be 10⋅7 %. Children aged 24-59 months were protected from WaSt (adjusted odds ratio (AOR) 0⋅40, 95 % confidence interval (CI) 0⋅21, 0⋅75). A higher prevalence of WaSt was associated with male sex (AOR 2⋅31, 95 % CI 1⋅13, 4⋅71), no history of being breastfed (AOR 3⋅57, 95 % CI 1⋅23, 10⋅39), acute diarrhoea (AOR 2⋅12, 95 % CI 1⋅12, 4⋅02) and family income sources of assistance from others (AOR 2⋅74, 95 % CI 1⋅08, 6⋅93) or salary work (AOR 2⋅22, 95 % CI 1⋅10, 4⋅47). Continued breast- and bottle-feeding were not associated with WaSt in children aged 6-23 months. Mothers' age, education and work status, family size and drinking water source were not associated with WaSt. Overall, we found that the prevalence of WaSt among marginalised children remained high. Interventions to improve household income, hygienic conditions and child feeding practices are necessary to promote child growth.

Association of full blood count findings with risk of mortality in children with Klebsiella pneumoniae bloodstream infection at a south african children's hospital

BACKGROUND

Bloodstream infection (BSI) caused by Klebsiella pneumoniae (KP), is a leading cause of hospital-associated childhood mortality. There are limited data on how poor outcomes of KPBSI can be predicted in poorly resourced areas. This study aimed to assess if the profile of differential counts from full blood counts (FBC) taken at two time points in children with KPBSI could be used to predict the risk of death.

METHODS

We conducted a retrospective study of a cohort of children admitted to hospital between 2006 and 2011 with KPBSI. FBC collected within 48 h (T1) of blood culture and 5-14 days later (T2), were reviewed. Differential counts were classified as abnormal if they were higher or lower than laboratory ranges for normal results. The risk of death was assessed for each category of differential counts. Risk ratios adjusted (aRR) for potential confounders were used to estimate the effect of cell counts on risk of death using multivariable analysis. Data were stratified by HIV status.

RESULTS

Of 296 children, median age 5 (IQR:2-13) months, 82 were HIV -infected. Ninety-five (32%) children with KPBSI died. Mortality in HIV-infected and uninfected children was 39/82 (48%) and 56/214 (26%), respectively (p < 0.001). Independent associations with mortality were observed with leucopenia, neutropenia and thrombocytopenia. Risk of mortality in HIV-uninfected children with thrombocytopenia at T1 and T2 was aRR 2.5 (95% CI: 1.34-4.64) and 3.18 (95% CI: 1.31-7.73) respectively, whereas the mortality risk in the HIV-infected group with thrombocytopaenia at T1 and T2 was aRR 1.99 (95% CI: 0.94-4.19) and 2.01 (95% CI: 0.65-5.99) respectively. Neutropenia in the HIV-uninfected group at T1 and T2, showed aRR 2.17 (95% CI: 1.22-3.88) and aRR 3.70 (95% CI 1.30-10.51) respectively, while in the HIV-infected group, they were aRR 1.18 (95% CI 0.69-2.03) and aRR 2.05 (95% CI 0.87-4.85) at similar time points. Leucopenia at T2 was associated with mortality in HIV-uninfected and HIV-infected patients, aRR 3.22 (95%CI 1.22-8.51) and aRR 2.34 (95% CI 1.09-5.04) respectively. Persistent high band cell percentage at T2 in HIV-infected children indicated a risk of mortality of aRR 2.91 (95% CI 1.20-7.06).

CONCLUSION

Abnormal neutrophil counts and thrombocytopenia are independently associated with mortality in children with KPBSI. In resource-limited countries haematological markers have the potential to predict KPBSI mortality.

Associations of dietary patterns with common infections and antibiotic use among Finnish preschoolers

Background

Preschoolers suffer frequently from infections. Although nutrition plays a key role in immune function, very little is known about the impact of overall diet on preschoolers' infections.

Objective

To assess the associations between dietary patterns, common infections and antibiotic use among Finnish preschoolers.

Design

The study included 721 3-6-year-old preschoolers participating in the cross-sectional DAGIS survey. Parents retrospectively reported the number of common colds, gastroenteritis episodes and antibiotic courses their children had acquired during the past year. Food consumption outside preschool hours was recorded using a food frequency questionnaire. Dietary patterns were derived from the consumption frequencies using principal component analysis. Associations between the thirds of the dietary pattern scores and the outcomes were analysed using logistic and negative binomial regression models.

Results

Prevalence of common colds was lower in moderate and high adherence to the sweets-and-treats pattern than in low adherence (prevalence ratio [PR]: 0.89, 95% confidence interval [CI]: 0.80-1.00, and PR: 0.88, 95% CI: 0.79-0.99, respectively) and higher in high adherence to the health-conscious pattern than in low adherence (PR: 1.13, 95% CI: 1.01-1.27) after adjusting for age, sex, number of children living in the same household, frequency of preschool attendance, family's highest education and probiotic use. The risk of ≥1 gastroenteritis episode and the prevalence of antibiotic courses were lower in moderate adherence to the sweets-and-treats pattern than in low adherence (odds ratio [OR]: 0.63, 95% CI: 0.44-0.92 and PR: 0.77, 95% CI: 0.59-1.00, respectively).

Conclusions

The results were unexpected. Parents who were most health-conscious of their children's diet might also have been more aware of their children's illness.

Metal ion content of internal organs in the calorically restricted Wistar rat

BACKGROUND

Despite the agreed principle that access to food is a human right, undernourishment and metal ion deficiencies are public health problems worldwide, exacerbated in impoverished or war-affected areas. It is known that maternal malnutrition causes growth retardation and affects behavioral and cognitive development of the newborn. Here we ask whether severe caloric restriction leads per se to disrupted metal accumulation in different organs of the Wistar rat.

METHODS

Inductively coupled plasma optical emission spectroscopy was used to determine the concentration of multiple elements in the small and large intestine, heart, lung, liver, kidney, pancreas, spleen, brain, spinal cord, and three skeletal muscles from control and calorically restricted Wistar rats. The caloric restriction protocol was initiated from the mothers prior to mating and continued throughout gestation, lactation, and post-weaning up to sixty days of age.

RESULTS

Both sexes were analyzed but dimorphism was rare. The pancreas was the most affected organ presenting a higher concentration of all the elements analyzed. Copper concentration decreased in the kidney and increased in the liver. Each skeletal muscle responded to the treatment differentially: Extensor Digitorum Longus accumulated calcium and manganese, gastrocnemius decreased copper and manganese, whereas soleus decreased iron concentrations. Differences were also observed in the concentration of elements between organs independently of treatment: The soleus muscle presents a higher concentration of Zn compared to the other muscles and the rest of the organs. Notably, the spinal cord showed large accumulations of calcium and half the concentration of zinc compared to brain. X-ray fluorescence imaging suggests that the extra calcium is attributable to the presence of ossifications whereas the latter finding is attributable to the low abundance of zinc synapses in the spinal cord.

CONCLUSION

Severe caloric restriction did not lead to systemic metal deficiencies but caused instead specific metal responses in few organs.

Impact of childhood malnutrition and intestinal microbiota on MDR infections

The global burden of infection from MDR organisms (MDROs) disproportionately affects children residing in low- and middle-income countries and those with increased healthcare exposure. These populations have high rates of malnutrition making them increasingly vulnerable to infection with intestinal-derived pathogens. Malnourished children experience increased incidence of intestinal carriage and invasive infection with intestinal-derived MDROs including ESBL- and carbapenemase-producing Enterobacterales. However, the relationship between malnutrition and MDRO infection remains to be clearly defined. Impairment in intestinal barrier function and innate and adaptive immunity in malnutrition increases the risk for infection with intestinal-derived pathogens, and there is an increasing appreciation of the role of the intestinal microbiota in this process. Current evidence from human studies and animal models suggests that diet and the intestinal microbiota influence each other to determine nutritional status, with important implications for infectious outcomes. These insights are crucial to developing microbiota-targeted strategies aimed at reversing the growing burden of MDRO infections in malnourished populations worldwide.

Roles of sex hormones in mediating the causal effect of vitamin D on osteoporosis: A two-step Mendelian randomization study

Background

Although 25-hydroxyvitamin D [25(OH)D] is a risk factor for osteoporosis, it is not clear whether sex hormones mediate this casual association. We aimed to explore how sex hormones affect the association between 25(OH)D and osteoporosis to provide meaningful insights on the underlying mechanisms from a genetic perspective.

Methods

Genetic variations in 25(OH)D, total testosterone (TT), androstenedione (A4), estradiol (E2), and testosterone/17β-estradiol (T/E2) were determined through summary statistics. Taking osteoporosis as the outcome (FinnGen biobank, 332,020 samples), we conducted a Mendelian randomization (MR) analysis to establish the association between 25(OH)D and these sex hormones. The two-step MR analysis quantified the mediatory effects of sex hormones on osteoporosis. The results were further verified by pleiotropy and heterogeneity analyses.

Results

MR results showed that 25(OH)D (OR= 1.27, p = 0.04) and TT (OR= 1.25, p = 0.04) had a causal effect on osteoporosis. No significant associations were observed between the other sex hormones (A4, E2, and T/E2) and osteoporosis (p&gt;0.05). Sensitivity analysis (p&gt;0.05) confirmed the robustness of the MR results. The two-step MR analysis provided evidence that the mediatory effect of TT was 0.014 (the percentage of TT mediation was 5.91%). Moreover, the direct effect of 25(OH)D on osteoporosis was 0.221. A4, E2, and T/E2 were not considered as potential mediators of the role of 25(OH)D as a risk factor for OP.

Conclusion

This study, through MR analysis, showed that TT mediates the causal effect of 25(OH)D on osteoporosis. Interventions targeting TT, therefore, have the potential to substantially reduce the burden of osteoporosis attributable to high 25(OH)D.

Childhood Body Mass Index (BMI) and the Risk of Infection: A Narrative Review

Context: Infectious diseases are still one of the main causes of morbidity and mortality in children, especially in developing countries. In various studies, the weight of children has been found to be influential in the risk of occurrence of these diseases or their severity, and sufficient information on this matter can be important in improving the management and prognosis of patients. This study aimed to determine the impact of being underweight or obese on the risk of infection in children Evidence Acquisition: The ISI Web of Sciences, Scopus, PubMed, and Google Scholar databases were reviewed for relevant articles published from 2010 to 2022. The keywords used included: Infections, body mass index, obesity, thinness, underweight, and child. Results: Studies show that underweight children are associated with an increased risk of various parasitic, viral, and bacterial infections or their severity. Being overweight and obese have received less attention, but they have been shown to be effective in some respiratory and urinary infections in children. Conclusions: According to obtained results, being underweight or obese has been linked to an increased risk of various parasitic, viral, and bacterial infections or their severity in children. Therefore, determining the weight of children, even in emergency cases, and considering it, along with other initial evaluations of children with infection, can be effective in improving the management and prognosis of these children.

Narrative Review: The Effect of Vitamin A Deficiency on Gut Microbiota and Their Link with Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders defined by a lack of social behaviors, repetitive behaviors and nonverbal interactions, such as limited eye contact, facial expression, and body gesturing. It is not a single condition, but rather a multi-factorial disorder caused by hereditary and non-genetic risk factors, as well as their interaction. According to several studies, the gut microbiota may have a role in the pathophysiology of autism spectrum disorder. Various studies have found differences in the composition of the gastrointestinal (GI) microbiota in children with ASD compared to unaffected siblings and/or healthy unrelated controls. The processes that relate the gut microbiota to brain dysfunctions (the gut-brain axis) in ASD are yet to be fully understood. However, the differences in the gastrointestinal composition might be due to vitamin A deficiency because vitamin A (VA) plays a role in the regulation of the intestinal microbiota. This narrative review discusses the impact of vitamin A deficiency on the gut microbiota composition and tries to understand how this may contribute for the development and severity of ASD.

Assessment of knowledge and socioeconomic status of caregivers of children with malnutrition at a district hospital in Ghana

Background

Malnutrition is a significant public health problem and is a major cause of morbidity and mortality in children.

Aims

To assess knowledge and socioeconomic status of caregivers of children under 5 years with malnutrition at a district hospital in Ghana.

Methods

Case Report forms were used to gather data in a cross-sectional study which was carried out among 189 caregivers and their children aged from zero to fifty-nine months at the Out-Patient Department clinic.

Results

Most (80.95%) children had marasmus. Sixty-two point four-two percent had severe wasting, while 35.45% had mild stunting. The rest, 21.69% had moderate stunting; while only 2.12% severe stunting. Almost all caregivers (94.71%) had heard of exclusive breast feeding as a good feeding practice but only 58.20% practiced it. Most caregivers (68.26%) had no education or only up to basic level, p=0.035. The average number of children per family was 4.8 per household (SD: 1.69) with majority of them (64.55%) having 4-6 children per family and 13.23% of them had more than 7 children per family, p=0.009. More than a third (37.04%) of the caregivers earned less than a hundred Ghana cedis (GhC 100 [US$ 19] per month and 50.26% of them earned between GhC 101 (US$ 19) and GhC 500 (US$ 96) per month.

Conclusion

Lower level of caregivers' education and large family size were risk factors for developing malnutrition among children.

Bee Pollen as Functional Food: Insights into Its Composition and Therapeutic Properties

Bee pollen is a hive product made up of flower pollen grains, nectar, and bee salivary secretions that beekeepers can collect without damaging the hive. Bee pollen, also called bee-collected pollen, contains a wide range of nutritious elements, including proteins, carbs, lipids, and dietary fibers, as well as bioactive micronutrients including vitamins, minerals, phenolic, and volatile compounds. Because of this composition of high quality, this product has been gaining prominence as a functional food, and studies have been conducted to show and establish its therapeutic potential for medical and food applications. In this context, this work aimed to provide a meticulous summary of the most relevant data about bee pollen, its composition—especially the phenolic compounds—and its biological and/or therapeutic properties as well as the involved molecular pathways.

Moderate and Severe Congenital Heart Diseases Adversely Affect the Growth of Children in Italy: A Retrospective Monocentric Study

Children with congenital heart disease (CHD) are at increased risk for undernutrition. The aim of our study was to describe the growth parameters of Italian children with CHD compared to healthy children. We performed a cross-sectional study collecting the anthropometric data of pediatric patients with CHD and healthy controls. WHO and Italian z-scores for weight for age (WZ), length/height for age (HZ), weight for height (WHZ) and body mass index (BMIZ) were collected. A total of 657 patients (566 with CHD and 91 healthy controls) were enrolled: 255 had mild CHD, 223 had moderate CHD and 88 had severe CHD. Compared to CHD patients, healthy children were younger (age: 7.5 ± 5.4 vs. 5.6 ± 4.3 years, p = 0.0009), taller/longer (HZ: 0.14 ± 1.41 vs. 0.62 ± 1.20, p < 0.002) and heavier (WZ: -0,07 ± 1.32 vs. 0.31 ± 1.13, p = 0.009) with no significant differences in BMIZ (-0,14 ± 1.24 vs. -0.07 ± 1.13, p = 0.64) and WHZ (0.05 ± 1.47 vs. 0.43 ± 1.07, p = 0.1187). Moderate and severe CHD patients presented lower z-scores at any age, with a more remarkable difference in children younger than 2 years (WZ) and older than 5 years (HZ, WZ and BMIZ). Stunting and underweight were significantly more present in children affected by CHD (p < 0.01). In conclusion, CHD negatively affects the growth of children based on the severity of the disease, even in a high-income country, resulting in a significant percentage of undernutrition in this population.

Malnutrition-related parasite dissemination from the skin in visceral leishmaniasis is driven by PGE2-mediated amplification of CCR7-related trafficking of infected inflammatory monocytes

People are infected with Leishmania donovani when the parasite is deposited in the dermis during the blood meal of the sand fly vector. Most infected people develop a subclinical latent infection, but some develop progressive visceral leishmaniasis. Malnutrition is a risk factor for the development of active VL. We previously demonstrated increased parasite dissemination from the skin to visceral organs in a murine model of malnutrition. Here we investigated the mechanism of early parasite dissemination. After delivery of L. donovani to the skin, we found enhanced capture of parasites by inflammatory monocytes and neutrophils in the skin of malnourished mice. However, parasite dissemination in malnourished mice was driven primarily by infected inflammatory monocytes, which showed increased CCR7 expression, greater intrinsic migratory capacity, and increased trafficking from skin to spleen. PGE2 production, which was increased at the site of skin infection, increased monocyte CCR7 expression and promoted CCR7-related monocyte-mediated early parasite dissemination in malnourished mice. Parasite dissemination in monocytes was reduced by inhibition of PGE2, knockdown or silencing of CCR7 in monocytes, and depletion of inflammatory monocytes through administration of diphtheria toxin to CSFR1-DTR transgenic mice that have monocyte-specific DT receptor expression. CCR7-driven trafficking of infected inflammatory monocytes through the lymph node was accompanied by increased expression of its ligands CCL19 and CCL21. These results show that the CCR7/PGE2 axis is responsible for the increased trafficking of L. donovani-infected inflammatory monocytes from the skin to the spleen in the malnourished host. Undernutrition and production of PGE2 are potential targets to reduce the risk of people developing VL. Nutritional interventions that target improved immune function and reduced PGE2 synthesis should be studied in people at risk of developing VL.

The predictors of catheter-related bloodstream infections in patients undergoing hemodialysis: A single center experience

BACKGROUND

Here we aimed to investigate the predictors of catheter-related bloodstream infections (CRBSI) in patients with acute kidney injury or chronic kidney disease who required renal replacement therapy through a non-tunneled hemodialysis catheter.

METHODS

A total of 111 patients who received non-tunneled hemodialysis catheters were retrospectively evaluated. Patients were divided into two groups; those who developed CRBSI and those who did not. Patient's demographic data, laboratory results at admission, information regarding catheter infections, and culture results were obtained from electronic medical records.

RESULTS

The mean age of the patients was 64 ± 16 years, and 51 of them were male. CRBSI occurred in 14 patients (12.6%). Admission serum albumin level (OR: 0.119, 95% CI: 0.019-0.756, p = 0.024), admission mean platelet volume (OR: 2.207, 95% CI: 1.188-4.100, p = 0.012) and catheter duration (OR: 1.580, 95% CI: 1.210-2.064, p = 0.001) were independent predictors for the CRBSI development. ROC curve analysis demonstrated that a catheter duration of 22 days was predictive for presence of CRBSI (78% sensitivity, 76% specificity, AUC: 0.825, 95% CI: 0.724-0.925, p < 0.001).

CONCLUSIONS

Prolonged catheter duration, low serum albumin, and high mean platelet volume independently predict the development of CRBSI in patients undergoing hemodialysis for acute kidney injury or chronic kidney disease.

Childhood Anemia and Risk for Acute Respiratory Infection, Gastroenteritis, and Urinary Tract Infection: A Systematic Review

Objective Children younger than 5 years, particularly children below 2 years, are among the most vulnerable groups for developing anemia and infections. This review is intended to assess the association between anemia and childhood acute respiratory infections (ARTIs), acute gastroenteritis (AGE), and urinary tract infections (UTIs).

Methods PubMed was searched for published articles from January 2000 to August 2021 in English using the following terms: anemia and acute respiratory tract infections in children; anemia and UTIs in children; anemia and AGE in children. The data extraction were conducted by two investigators using the same methodology. Using descriptive statistics, the data from different sources were synthesized, including medians and ranges.

Results A total of 426 articles and 27 original articles and 1 systematic review were included. Iron deficiency anemia is common among children between 6 months and 3 years of age. This age group can be considered a highly susceptible age for contraction of ARTI and AGE. Children below 5 years suffer five to six episodes of acute ARTI per year on average, and pneumonia accounts for the highest number of deaths, which is around 1.1 million each year. When considered, the odds ratio of anemia to increase the susceptibility of contracting lower ARTI would range from 2 to 5.7. Also, anemic children were 10 times more susceptible to developing acute recurrent ARTI and 4 times more susceptible to contracting pneumonia. Respiratory syncytial virus is the commonest viral etiology. Anemia would increase the risk of diarrhea by 2.9-fold in toddlers, while mild anemia, moderate anemia, and severe anemia would increase the susceptibility to contract AGE by 1.6, 1.6, and 8.9 times, respectively. Rotavirus is the commonest etiology. Some studies observed a protective effect of mild to moderate iron-deficient anemia from respiratory infections.

Conclusion Infectious disease imposes a heavy burden on the health sector in a country. The highest susceptibility for infections and the development of anemia would be due to inadequate nutrition supplementation to meet the demand during rapid body growth. Therefore, based on the available evidence, one can take the necessary steps to reduce the infectious disease burden by correcting the anemia status in children.

Mechanosensing in macrophages and dendritic cells in steady-state and disease

Macrophages and dendritic cells are myeloid cells that play critical roles in immune responses. Macrophages help to maintain homeostasis through tissue regeneration and the clearance of dead cells, but also mediate inflammatory processes against invading pathogens. As the most potent antigen-presenting cells, dendritic cells are important in connecting innate to adaptive immune responses via activation of T cells, and inducing tolerance under physiological conditions. While it is known that macrophages and dendritic cells respond to biochemical cues in the microenvironment, the role of extracellular mechanical stimuli is becoming increasingly apparent. Immune cell mechanotransduction is an emerging field, where accumulating evidence suggests a role for extracellular physical cues coming from tissue stiffness in promoting immune cell recruitment, activation, metabolism and inflammatory function. Additionally, many diseases such as pulmonary fibrosis, cardiovascular disease, cancer, and cirrhosis are associated with changes to the tissue biophysical environment. This review will discuss current knowledge about the effects of biophysical cues including matrix stiffness, topography, and mechanical forces on macrophage and dendritic cell behavior under steady-state and pathophysiological conditions. In addition, we will also provide insight on molecular mediators and signaling pathways important in macrophage and dendritic cell mechanotransduction.

A nomogram for predicting the risk of mortality in patients with acute pancreatitis and Gram-negative bacilli infection

OBJECTIVE

Gram-negative bacilli (GNB) are common pathogens of infection in severe acute pancreatitis (SAP), and their occurrence increases the mortality of SAP. Early identification of SAP severity and prognosis is of great significance to SAP treatment. This study explored risk factors for mortality in patients with SAP and GNB infection and established a model for early prediction of the risk of death in GNB-infected SAP patients.

METHODS

Patients diagnosed with SAP from January 1, 2016, to March 31, 2022, were included, and their baseline clinical characteristics were collected. Univariate logistic regression analysis was performed to screen for death related variables, and concurrently, a Boruta analysis was performed to identify potentially important clinical features associated with mortality. The intersection of the two results was taken for further multivariate logistic regression analysis. A logistic regression model was constructed according to the independent risk factor of death and then visualized with a nomogram. The performance of the model was further validated in the training and validation cohort.

RESULTS

A total of 151 patients with SAP developed GNB infections. Univariate logistic regression analysis identified 11 variables associated with mortality. The Boruta analysis identified 11 clinical features, and 4 out of 9 clinical variables: platelet counts (odds ratio [OR] 0.99, 95% confidence interval [CI] 0.99-1.00; p = 0.007), hemoglobin (OR 0.96, 95% CI 0.92-1; p = 0.037), septic shock (OR 6.33, 95% CI 1.12-43.47; p = 0.044), and carbapenem resistance (OR 7.99, 95% CI 1.66-52.37; p = 0.016), shared by both analyses were further selected as independent risk factors by multivariate logistic regression analysis. A nomogram was used to visualize the model. The model demonstrated good performance in both training and validation cohorts with recognition sensitivity and specificity of 96% and 80% in the training cohort and 92.8% and 75% in the validation cohort, respectively.

CONCLUSION

The nomogram can accurately predict the mortality risk of patients with SAP and GNB infection. The clinical application of this model allows early identification of the severity and prognosis for patients with SAP and GNB infection and identification of patients requiring urgent management thus allowing rationalization of treatment options and improvements in clinical outcomes.

Death from human cytomegalovirus infection in a girl with congenital thymic dysplasia

We report the case of a girl with congenital thymic dysplasia and refractory disseminated Human Cytomegalovirus (CMV) infection diagnosed by autopsy. Additionally, she was diagnosed with T-cell lymphopenia immunodeficiency and received antiviral therapy with ganciclovir (GCV) /valganciclovir (V-GCV) and enhanced foscarnet. The CMV viral load (VL) monitoring was elevated with retinitis, interstitial pneumonia, and hepatitis. The phenotype of T-cell lymphopenia was uncertain, which limited any alternative therapy by whole-exome sequencing (WES) and lymphocyte subset panel until autopsy. The girl died of progressive respiratory failure and septic shock at ten months of age. Severe disseminated CMV infection typically develops in infants with primary maternal infections and occurs earlier during gestation and in people with a weakened host immune system. Individuals with CMV infection with initial immunodeficiency are associated with a poor prognosis, which is similar to patients with secondary immunodeficiency. This case describes the difficult treatment and prognosis of CMV infection in patients with congenital immunodeficiency, highlighting the importance of early aggressive anti-CMV antiviral therapy in immunodeficiencies, VL monitoring, drug resistance and the role of T-cells in CMV infection.

Moderate-to-Severe Malnutrition Identified by the Controlling Nutritional Status (CONUT) Score Is Significantly Associated with Treatment Failure of Periprosthetic Joint Infection

The prevalence and role of malnutrition in periprosthetic joint infection (PJI) remain unclear. This study aimed to use measurable nutritional screening tools to assess the prevalence of malnutrition in PJI patients during two-stage exchange arthroplasty and to explore the association between malnutrition and treatment failure. Our study retrospectively included 183 PJI cases who underwent 1st stage exchange arthroplasty and had available nutritional parameters, of which 167 proceeded with 2nd stage reimplantation. The recently proposed Musculoskeletal Infection Society (MSIS) Outcome Reporting Tool was used to determine clinical outcomes. The Controlling Nutritional Status (CONUT), Nutritional Risk Index (NRI), and Naples Prognostic Score (NPS) were used to identify malnutrition at 1st and 2nd stage exchange, respectively. Multivariate logistic regression analyses were performed to determine the association between malnutrition and treatment failure. Restricted cubic spline models were further used to explore the dose−response association. Additionally, risk factors for moderate-to-severe malnutrition were evaluated. Malnourished patients identified by CONUT, NPS, and NRI accounted for 48.1% (88/183), 98.9% (181/183), and 55.7% (102/183) of patients at 1st stage, and 9.0% (15/167), 41.9% (70/167), and 43.1% (72/167) at 2nd stage, indicating a significant improvement in nutritional status. We found that poorer nutritional status was a predictor of treatment failure, with CONUT performing best as a predictive tool. Moderate-to-severe malnutrition at 1st stage identified by CONUT was significantly related to treatment failure directly caused by PJI (odds ratio [OR] = 5.86), while the OR was raised to 12.15 at 2nd stage (OR = 12.15). The linear dose−response associations between them were also confirmed (P for nonlinearity at both 1st and 2nd stage > 0.05). As for total treatment failure, moderate-to-severe malnutrition as determined by CONUT was associated with a 1.96-fold and 8.99-fold elevated risk at the 1st and 2nd stages, respectively. Age ≥ 68 years (OR = 5.35) and an increased number of previous surgeries (OR = 2.04) may be risk factors for moderate-to-severe malnutrition. Overall, the prevalence of malnutrition in PJI patients is very high. Given the strong association between moderate-to-severe malnutrition identified by CONUT and PJI treatment failure, COUNT could be a promising tool to evaluate the nutritional status of PJI patients to optimize treatment outcomes.

Choline, DHA, and Diarrheal Disease Associated with Growth Faltering in a Case-Control Study

Background

Children with recurrent infectious diarrhea are susceptible to growth faltering. DHA and choline may play a role in this relationship due to their involvement in lipid metabolism, gut immunity, and inflammatory pathways.

Objectives

This study aimed to characterize the contributions made by DHA and choline status and enteric damage in young children in the association between diarrheal illness and child growth.

Methods

A longitudinal case-control study was conducted among children aged 6-36 mo (N = 195) in Cap-Haitien, Haiti. Mother-child dyads were recruited from community health posts and outpatient clinics. Cases were defined as children experiencing acute diarrhea within the last 3 d and matched to healthy controls. Child anthropometry, dietary intake, and blood and stool samples were collected at baseline and follow-up. Plasma DHA, choline, and betaine were determined by LC-MS/MS methods (n = 49) and intestinal fatty acid-binding protein (I-FABP) by ELISA (n = 183). Multivariate regression models were applied with mediation analyses to examine associations and adjust for confounding factors.

Results

At baseline, mean plasma DHA concentrations (1.03 µg/mL; 95% CI: 0.91, 1.15) were not significantly different between cases and controls, nor was there a difference in mean plasma choline concentrations (4.5 µg/mL; 95% CI: 3.8, 5.1). Mean plasma I-FABP concentrations were significantly higher at follow-up in cases (3.34; 95% CI: 3.28, 3.40) than controls (3.20; 95% CI: 3.13, 3.27; P = 0.002). In adjusted multilinear regression models, higher plasma DHA concentrations at follow-up were associated with a negative change in weight-age z score (P = 0.016), and follow-up I-FABP was inversely associated with height-age z score (P = 0.035). No interaction or mediation effects were found.

Conclusions

I-FABP concentrations were significantly higher in cases as compared with controls at follow-up, suggesting ongoing enteric damage and increased risk for malnutrition. Plasma DHA and I-FABP may have a role in childhood growth outcomes.

Thymus, undernutrition, and infection: Approaching cellular and molecular interactions

Undernutrition remains a major issue in global health. Low protein-energy consumption, results in stunting, wasting and/or underweight, three deleterious forms of malnutrition that affect roughly 200 million children under the age of five years. Undernutrition compromises the immune system with the generation of various degrees of immunodeficiency, which in turn, renders undernourished individuals more sensitive to acute infections. The severity of various infectious diseases including visceral leishmaniasis (VL), influenza, and tuberculosis is associated with undernutrition. Immunosuppression resulting from protein-energy undernutrition severely impacts primary and secondary lymphoid organs involved in the response to related pathogens. The thymus-a primary lymphoid organ responsible for the generation of T lymphocytes-is particularly compromised by both undernutrition and infectious diseases. In this respect, we will discuss herein various intrathymic cellular and molecular interactions seen in undernutrition alone or in combination with acute infections. Many examples illustrated in studies on humans and experimental animals clearly revealed that protein-related undernutrition causes thymic atrophy, with cortical thymocyte depletion. Moreover, the non-lymphoid microenvironmental compartment of the organ undergoes important changes in thymic epithelial cells, including their secretory products such as hormones and extracellular matrix proteins. Of note, deficiencies in vitamins and trace elements also induce thymic atrophy. Interestingly, among the molecular interactions involved in the control of undernutrition-induced thymic atrophy is a hormonal imbalance with a rise in glucocorticoids and a decrease in leptin serum levels. Undernutrition also yields a negative impact of acute infections upon the thymus, frequently with the intrathymic detection of pathogens or their antigens. For instance, undernourished mice infected with Leishmania infantum (that causes VL) undergo drastic thymic atrophy, with significant reduction in thymocyte numbers, and decreased levels of intrathymic chemokines and cytokines, indicating that both lymphoid and microenvironmental compartments of the organ are affected. Lastly, recent data revealed that some probiotic bacteria or probiotic fermented milks improve the thymus status in a model of malnutrition, thus raising a new field for investigation, namely the thymus-gut connection, indicating that probiotics can be envisioned as a further adjuvant therapy in the control of thymic changes in undernutrition accompanied or not by infection.

The Combined Escherichia coli Nissle 1917 and Tryptophan Treatment Modulates Immune and Metabolome Responses to Human Rotavirus Infection in a Human Infant Fecal Microbiota-Transplanted Malnourished Gnotobiotic Pig Model

Human rotavirus (HRV) is a major cause of childhood diarrhea in developing countries where widespread malnutrition contributes to the decreased oral vaccine efficacy and increased prevalence of other enteric infections, which are major concerns for global health. Neonatal gnotobiotic (Gn) piglets closely resemble human infants in their anatomy, physiology, and outbred status, providing a unique model to investigate malnutrition, supplementations, and HRV infection. To understand the molecular signatures associated with immune enhancement and reduced diarrheal severity by Escherichia coli Nissle 1917 (EcN) and tryptophan (TRP), immunological responses and global nontargeted metabolomics and lipidomics approaches were investigated on the plasma and fecal contents of malnourished pigs transplanted with human infant fecal microbiota and infected with virulent (Vir) HRV. Overall, EcN + TRP combined (rather than individual supplement action) promoted greater and balanced immunoregulatory/immunostimulatory responses associated with greater protection against HRV infection and disease in malnourished humanized piglets. Moreover, EcN + TRP treatment upregulated the production of several metabolites with immunoregulatory/immunostimulatory properties: amino acids (N-acetylserotonin, methylacetoacetyl-CoA), lipids (gamma-butyrobetaine, eicosanoids, cholesterol-sulfate, sphinganine/phytosphingosine, leukotriene), organic compound (biliverdin), benzenoids (gentisic acid, aminobenzoic acid), and nucleotides (hypoxathine/inosine/xanthine, cytidine-5'-monophosphate). Additionally, the levels of several proinflammatory metabolites of organic compounds (adenosylhomocysteine, phenylacetylglycine, urobilinogen/coproporphyrinogen) and amino acid (phenylalanine) were reduced following EcN + TRP treatment. These results suggest that the EcN + TRP effects on reducing HRV diarrhea in neonatal Gn pigs were at least in part due to altered metabolites, those involved in lipid, amino acid, benzenoids, organic compounds, and nucleotide metabolism. Identification of these important mechanisms of EcN/TRP prevention of HRV diarrhea provides novel targets for therapeutics development. IMPORTANCE Human rotavirus (HRV) is the most common cause of viral gastroenteritis in children, especially in developing countries, where the efficacy of oral HRV vaccines is reduced. Escherichia coli Nissle 1917 (EcN) is used to treat enteric infections and ulcerative colitis while tryptophan (TRP) is a biomarker of malnutrition, and its supplementation can alleviate intestinal inflammation and normalize intestinal microbiota in malnourished hosts. Supplementation of EcN + TRP to malnourished humanized gnotobiotic piglets enhanced immune responses and resulted in greater protection against HRV infection and diarrhea. Moreover, EcN + TRP supplementation increased the levels of immunoregulatory/immunostimulatory metabolites while decreasing the production of proinflammatory metabolites in plasma and fecal samples. Profiling of immunoregulatory and proinflammatory biomarkers associated with HRV perturbations will aid in the identification of treatments against HRV and other enteric diseases in malnourished children.

A Crisis within a Crisis: COVID-19 and Hidden Hunger

The coronavirus (Covid-19), which was recognized in December 2019 and quickly became a worldwide pandemic, has become a significant public health problem. When it comes to the immune and infectious diseases, effects of nutrition on the inflammatory system cannot be ignored. Micronutrients, including vitamins and minerals, are critical to a well-functioning immune system and vital in supporting nutritional and health well-being. However, there are serious vitamin and mineral deficiencies worldwide known as "Hidden Hunger". It is thought that need for micronutrients in nutrition may increase especially during Covid-19 pandemic process. Therefore, it is essential to take precautions regarding the formation of hidden hunger. While the underlying determinants and complexity of malnutrition have been better understood through years of research, these researches have been limited in scaling, developing and implementing nutrition and food system approaches closely related to sustainable agriculture targeting food diversity and livelihoods.. In this review, the Covid-19 pandemic and its interactions with health, environment, food and their relationship to chronic micronutrient deficiencies, known as 'hidden hunger,' which affected more than two billion people worldwide, are evaluated.

Inflammatory stimuli alter bone marrow composition and compromise bone health in the malnourished host

Inflammation has a role in the pathogenesis of childhood malnutrition. We investigated the effect of malnutrition and inflammatory challenge on bone marrow composition and bone health. We studied an established murine model of moderate acute malnutrition at baseline and after acute inflammatory challenge with bacterial lipopolysaccharide (LPS), a surrogate of Gram-negative bacterial sepsis, or Leishmania donovani, the cause of visceral leishmaniasis. Both of these infections cause significant morbidity and mortality in malnourished children. Of the 2 stimuli, LPS caused more pronounced bone marrow changes that were amplified in malnourished mice. LPS challenge led to increased inflammatory cytokine expression (Il1b, Il6, and Tnf), inflammasome activation, and inflammatory monocyte accumulation in the bone marrow of malnourished mice. Depletion of inflammatory monocytes in Csfr1-LysMcre-DT malnourished mice significantly reduced the inflammasome activation and IL1-ß production after LPS challenge. The inflammatory challenge also led to increased expansion of mesenchymal stem cells (MSCs), bone marrow adiposity, and expression of genes (Pparg, Adipoq, and Srbp1) associated with adipogenesis in malnourished mice. This suggests that inflammatory challenge promotes differentiation of BM MSCs toward the adipocyte lineage rather than toward bone-forming osteoblasts in the malnourished host. Concurrent with this reduced osteoblastic potential there was an increase in bone-resorbing osteoclasts, enhanced osteoclast activity, upregulation of inflammatory genes, and IL-1B involved in osteoclast differentiation and activation. The resulting weakened bone formation and increased bone resorption would contribute to the bone fragility associated with malnutrition. Lastly, we evaluated the effect of replacing lipid rich in omega-6 fatty acids (corn oil) with lipid-rich in omega-3 fatty acids (fish oil) in the nutrient-deficient diet. LPS-challenged malnourished mice that received dietary fish oil showed decreased expression of inflammatory cytokines and Rankl and reduced osteoclast differentiation and activation in the bone marrow. This work demonstrates that the negative effect of inflammatory challenge on bone marrow is amplified in the malnourished host. Increasing dietary intake of omega-3 fatty acids may be a means to reduce inflammation and improve bone health in malnourished children.

Malnutrition and maternal vaccination against typhoid toxin

Children are particularly susceptible to typhoid fever caused by the bacterial pathogen Salmonella Typhi. Typhoid fever is prevalent in developing countries where diets can be less well-balanced. Here, using a murine model, we investigated the role of the macronutrient composition of the diet in maternal vaccination efficacies of two subunit vaccines targeting typhoid toxin: ToxoidVac and PltBVac. We found that maternal vaccinations protected all offspring against a lethal-dose typhoid toxin challenge in a balanced, normal diet (ND) condition, but the declined protection in a malnourished diet (MD) condition was observed in the PltBVac group. Despite the comparable antibody titers in both MD and ND mothers, MD offspring had a significantly lower level of typhoid toxin neutralizing antibodies than their ND counterparts. We observed a lower expression of the neonatal Fc receptor on the yolk sac of MD mothers than in ND mothers, agreeing with the observed lower antibody titers in MD offspring. Protein supplementation to MD diets, but not fat supplementation, increased FcRn expression and protected all MD offspring from the toxin challenge. Similarly, providing additional typhoid toxin-neutralizing antibodies to MD offspring was sufficient to protect all MD offspring from the toxin challenge. These results emphasize the significance of balanced/normal diets for a more effective maternal vaccination transfer to their offspring.