Phenotypic and molecular characterization of β-lactamase-producing Klebsiella species among children discharged from hospital in Western Kenya

BACKGROUND

The emergence and spread of β-lactamase-producing Klebsiella spp. has been associated with a substantial healthcare burden resulting in therapeutic failures. We sought to describe the proportion of phenotypic resistance to commonly used antibiotics, characterize β-lactamase genes among isolates with antimicrobial resistance (AMR), and assess the correlates of phenotypic AMR in Klebsiella spp. isolated from stool or rectal swab samples collected from children being discharged from hospital.

METHODS

We conducted a cross-sectional study involving 245 children aged 1-59 months who were being discharged from hospitals in western Kenya between June 2016 and November 2019. Whole stool or rectal swab samples were collected and Klebsiella spp. isolated by standard microbiological culture. β-lactamase genes were detected by PCR whilst phenotypic antimicrobial susceptibility was determined using the disc diffusion technique following standard microbiology protocols. Descriptive analyses were used to characterize phenotypic AMR and carriage of β-lactamase-producing genes. The modified Poisson regression models were used to assess correlates of phenotypic beta-lactam resistance.

RESULTS

The prevalence of β-lactamase carriage among Klebsiella spp. isolates at hospital discharge was 62.9% (154/245). Antibiotic use during hospitalization (adjusted prevalence ratio [aPR] = 4.51; 95%CI: 1.79-11.4, p < 0.001), longer duration of hospitalization (aPR = 1.42; 95%CI: 1.14-1.77, p < 0.002), and access to treated water (aPR = 1.38; 95%CI: 1.12-1.71, p < 0.003), were significant predictors of phenotypically determined β-lactamase. All the 154 β-lactamase-producing Klebsiella spp. isolates had at least one genetic marker of β-lactam/third-generation cephalosporin resistance. The most prevalent genes were blaCTX-M 142/154 (92.2%,) and blaSHV 142/154 (92.2%,) followed by blaTEM 88/154 (57.1%,) and blaOXA 48/154 (31.2%,) respectively.

CONCLUSION

Carriage of β-lactamase producing Klebsiella spp. in stool is common among children discharged from hospital in western Kenya and is associated with longer duration of hospitalization, antibiotic use, and access to treated water. The findings emphasize the need for continued monitoring of antimicrobial susceptibility patterns to inform the development and implementation of appropriate treatment guidelines. In addition, we recommend measures beyond antimicrobial stewardship and infection control within hospitals, improved sanitation, and access to safe drinking water to mitigate the spread of β-lactamase-producing Klebsiella pathogens in these and similar settings.

Azithromycin for Bacterial Watery Diarrhea: A Reanalysis of the AntiBiotics for Children With Severe Diarrhea (ABCD) Trial Incorporating Molecular Diagnostics

BACKGROUND

Bacterial pathogens cause substantial diarrhea morbidity and mortality among children living in endemic settings, yet antimicrobial treatment is only recommended for dysentery or suspected cholera.

METHODS

AntiBiotics for Children with severe Diarrhea was a 7-country, placebo-controlled, double-blind efficacy trial of azithromycin in children 2-23 months of age with watery diarrhea accompanied by dehydration or malnutrition. We tested fecal samples for enteric pathogens utilizing quantitative polymerase chain reaction to identify likely and possible bacterial etiologies and employed pathogen-specific cutoffs based on genomic target quantity in previous case-control diarrhea etiology studies to identify likely and possible bacterial etiologies.

RESULTS

Among 6692 children, the leading likely etiologies were rotavirus (21.1%), enterotoxigenic Escherichia coli encoding heat-stable toxin (13.3%), Shigella (12.6%), and Cryptosporidium (9.6%). More than one-quarter (1894 [28.3%]) had a likely and 1153 (17.3%) a possible bacterial etiology. Day 3 diarrhea was less common in those randomized to azithromycin versus placebo among children with a likely bacterial etiology (risk difference [RD]likely, -11.6 [95% confidence interval {CI}, -15.6 to -7.6]) and possible bacterial etiology (RDpossible, -8.7 [95% CI, -13.0 to -4.4]) but not in other children (RDunlikely, -0.3% [95% CI, -2.9% to 2.3%]). A similar association was observed for 90-day hospitalization or death (RDlikely, -3.1 [95% CI, -5.3 to -1.0]; RDpossible, -2.3 [95% CI, -4.5 to -.01]; RDunlikely, -0.6 [95% CI, -1.9 to .6]). The magnitude of risk differences was similar among specific likely bacterial etiologies, including Shigella.

CONCLUSIONS

Acute watery diarrhea confirmed or presumed to be of bacterial etiology may benefit from azithromycin treatment.

CLINICAL TRIALS REGISTRATION

NCT03130114.

Exploring Natural Immune Responses to Shigella Exposure Using Multiplex Bead Assays on Dried Blood Spots in High-Burden Countries: Protocol From a Multisite Diarrhea Surveillance Study

Background

Molecular diagnostics on human fecal samples have identified a larger burden of shigellosis than previously appreciated by culture. Evidence of fold changes in immunoglobulin G (IgG) to conserved and type-specific Shigella antigens could be used to validate the molecular assignment of type-specific Shigella as the etiology of acute diarrhea and support polymerase chain reaction (PCR)-based microbiologic end points for vaccine trials.

Methods

We will test dried blood spots collected at enrollment and 4 weeks later using bead-based immunoassays for IgG to invasion plasmid antigen B and type-specific lipopolysaccharide O-antigen for Shigella flexneri 1b, 2a, 3a, and 6 and Shigella sonnei in Shigella-positive cases and age-, site-, and season-matched test-negative controls from all sites in the Enterics for Global Health (EFGH) Shigella surveillance study. Fold antibody responses will be compared between culture-positive, culture-negative but PCR-attributable, and PCR-positive but not attributable cases and test-negative controls. Age- and site-specific seroprevalence distributions will be identified, and the association between baseline antibodies and Shigella attribution will be estimated.

Conclusions

The integration of these assays into the EFGH study will help support PCR-based attribution of acute diarrhea to type-specific Shigella, describe the baseline seroprevalence of conserved and type-specific Shigella antibodies, and support correlates of protection for immunity to Shigella diarrhea. These insights can help support the development and evaluation of Shigella vaccine candidates.

Population Enumeration and Household Utilization Survey Methods in the Enterics for Global Health (EFGH): Shigella Surveillance Study

Background

Accurate estimation of diarrhea incidence from facility-based surveillance requires estimating the population at risk and accounting for case patients who do not seek care. The Enterics for Global Health (EFGH) Shigella surveillance study will characterize population denominators and healthcare-seeking behavior proportions to calculate incidence rates of Shigella diarrhea in children aged 6-35 months across 7 sites in Africa, Asia, and Latin America.

Methods

The Enterics for Global Health (EFGH) Shigella surveillance study will use a hybrid surveillance design, supplementing facility-based surveillance with population-based surveys to estimate population size and the proportion of children with diarrhea brought for care at EFGH health facilities. Continuous data collection over a 24 month period captures seasonality and ensures representative sampling of the population at risk during the period of facility-based enrollments. Study catchment areas are broken into randomized clusters, each sized to be feasibly enumerated by individual field teams.

Conclusions

The methods presented herein aim to minimize the challenges associated with hybrid surveillance, such as poor parity between survey area coverage and facility coverage, population fluctuations, seasonal variability, and adjustments to care-seeking behavior.

Data Management in Multicountry Consortium Studies: The Enterics For Global Health (EFGH) Shigella Surveillance Study Example

Background

Rigorous data management systems and planning are essential to successful research projects, especially for large, multicountry consortium studies involving partnerships across multiple institutions. Here we describe the development and implementation of data management systems and procedures for the Enterics For Global Health (EFGH) Shigella surveillance study-a 7-country diarrhea surveillance study that will conduct facility-based surveillance concurrent with population-based enumeration and a health care utilization survey to estimate the incidence of Shigella--associated diarrhea in children 6 to 35 months old.

Methods

The goals of EFGH data management are to utilize the knowledge and experience of consortium members to collect high-quality data and ensure equity in access and decision-making. During the planning phase before study initiation, a working group of representatives from each EFGH country site, the coordination team, and other partners met regularly to develop the data management systems for the study.

Results

This resulted in the Data Management Plan, which included selecting REDCap and SurveyCTO as the primary database systems. Consequently, we laid out procedures for data processing and storage, study monitoring and reporting, data quality control and assurance activities, and data access. The data management system and associated real-time visualizations allow for rapid data cleaning activities and progress monitoring and will enable quicker time to analysis.

Conclusions

Experiences from this study will contribute toward enriching the sparse landscape of data management methods publications and serve as a case study for future studies seeking to collect and manage data consistently and rigorously while maintaining equitable access to and control of data.

Shigella Detection and Molecular Serotyping With a Customized TaqMan Array Card in the Enterics for Global Health (EFGH): Shigella Surveillance Study

Background

Quantitative polymerase chain reaction (qPCR) targeting ipaH has been proven to be highly efficient in detecting Shigella in clinical samples compared to culture-based methods, which underestimate Shigella burden by 2- to 3-fold. qPCR assays have also been developed for Shigella speciation and serotyping, which is critical for both vaccine development and evaluation.

Methods

The Enterics for Global Health (EFGH) Shigella surveillance study will utilize a customized real-time PCR-based TaqMan Array Card (TAC) interrogating 82 targets, for the detection and differentiation of Shigella spp, Shigella sonnei, Shigella flexneri serotypes, other diarrhea-associated enteropathogens, and antimicrobial resistance (AMR) genes. Total nucleic acid will be extracted from rectal swabs or stool samples, and assayed on TAC. Quantitative analysis will be performed to determine the likely attribution of Shigella and other particular etiologies of diarrhea using the quantification cycle cutoffs derived from previous studies. The qPCR results will be compared to conventional culture, serotyping, and phenotypic susceptibility approaches in EFGH.

Conclusions

TAC enables simultaneous detection of diarrheal etiologies, the principal pathogen subtypes, and AMR genes. The high sensitivity of the assay enables more accurate estimation of Shigella-attributed disease burden, which is critical to informing policy and in the design of future clinical trials.

Microbiological Methods Used in the Enterics for Global Health Shigella Surveillance Study

Background

Shigella is a major cause of diarrhea in young children worldwide. Multiple vaccines targeting Shigella are in development, and phase 3 clinical trials are imminent to determine efficacy against shigellosis.

Methods

The Enterics for Global Health (EFGH) Shigella surveillance study is designed to determine the incidence of medically attended shigellosis in 6- to 35-month-old children in 7 resource-limited settings. Here, we describe the microbiological methods used to isolate and identify Shigella. We developed a standardized laboratory protocol for isolation and identification of Shigella by culture. This protocol was implemented across all 7 sites, ensuring consistency and comparability of results. Secondary objectives of the study are to determine the antibiotic resistance profiles of Shigella, compare isolation of Shigella from rectal swabs versus whole stool, and compare isolation of Shigella following transport of rectal swabs in Cary-Blair versus a modified buffered glycerol saline transport medium.

Conclusions

Data generated from EFGH using culture methods described herein can potentially be used for microbiological endpoints in future phase 3 clinical trials to evaluate vaccines against shigellosis and for other clinical and public health studies focused on these organisms.

Evaluation of Fecal Inflammatory Biomarkers to Identify Bacterial Diarrhea Episodes: Systematic Review and Protocol for the Enterics for Global Health Shigella Surveillance Study

Background

The measurement of fecal inflammatory biomarkers among individuals presenting to care with diarrhea could improve the identification of bacterial diarrheal episodes that would benefit from antibiotic therapy. We reviewed prior literature in this area and describe our proposed methods to evaluate 4 biomarkers in the Enterics for Global Health (EFGH) Shigella surveillance study.

Methods

We systematically reviewed studies since 1970 from PubMed and Embase that assessed the diagnostic characteristics of inflammatory biomarkers to identify bacterial diarrhea episodes. We extracted sensitivity and specificity and summarized the evidence by biomarker and diarrhea etiology. In EFGH, we propose using commercial enzyme-linked immunosorbent assays to test for myeloperoxidase, calprotectin, lipocalin-2, and hemoglobin in stored whole stool samples collected within 24 hours of enrollment from participants in the Bangladesh, Kenya, Malawi, Pakistan, Peru, and The Gambia sites. We will develop clinical prediction scores that incorporate the inflammatory biomarkers and evaluate their ability to identify Shigella and other bacterial etiologies of diarrhea as determined by quantitative polymerase chain reaction (qPCR).

Results

Forty-nine studies that assessed fecal leukocytes (n = 39), red blood cells (n = 26), lactoferrin (n = 13), calprotectin (n = 8), and myeloperoxidase (n = 1) were included in the systematic review. Sensitivities were high for identifying Shigella, moderate for identifying any bacteria, and comparable across biomarkers. Specificities varied depending on the outcomes assessed. Prior studies were generally small, identified red and white blood cells by microscopy, and used insensitive gold standard diagnostics, such as conventional bacteriological culture for pathogen detection.

Conclusions

Our evaluation of inflammatory biomarkers to distinguish diarrhea etiologies as determined by qPCR will provide an important addition to the prior literature, which was likely biased by the limited sensitivity of the gold standard diagnostics used. We will determine whether point-of-care biomarker tests could be a viable strategy to inform treatment decision making and increase appropriate targeting of antibiotic treatment to bacterial diarrhea episodes.

Diarrhea Case Surveillance in the Enterics for Global Health Shigella Surveillance Study: Epidemiologic Methods

Background

Shigella is a leading cause of acute watery diarrhea, dysentery, and diarrhea-attributed linear growth faltering, a precursor to stunting and lifelong morbidity. Several promising Shigella vaccines are in development and field efficacy trials will require a consortium of potential vaccine trial sites with up-to-date Shigella diarrhea incidence data.

Methods

The Enterics for Global Health (EFGH) Shigella surveillance study will employ facility-based enrollment of diarrhea cases aged 6-35 months with 3 months of follow-up to establish incidence rates and document clinical, anthropometric, and financial consequences of Shigella diarrhea at 7 country sites (Mali, Kenya, The Gambia, Malawi, Bangladesh, Pakistan, and Peru). Over a 24-month period between 2022 and 2024, the EFGH study aims to enroll 9800 children (1400 per country site) between 6 and 35 months of age who present to local health facilities with diarrhea. Shigella species (spp.) will be identified and serotyped from rectal swabs by conventional microbiologic methods and quantitative polymerase chain reaction. Shigella spp. isolates will undergo serotyping and antimicrobial susceptibility testing. Incorporating population and healthcare utilization estimates from contemporaneous household sampling in the catchment areas of enrollment facilities, we will estimate Shigella diarrhea incidence rates.

Conclusions

This multicountry surveillance network will provide key incidence data needed to design Shigella vaccine trials and strengthen readiness for potential trial implementation. Data collected in EFGH will inform policy makers about the relative importance of this vaccine-preventable disease, accelerating the time to vaccine availability and uptake among children in high-burden settings.

Prevalence and Correlates of Stunting among a High-Risk Population of Kenyan Children Recently Hospitalized for Acute Illnesses

Stunting (length/height-for-age z-score < -2) is associated with significant morbidity and mortality among children under 5 years of age in sub-Saharan Africa. Children who are stunted and recently hospitalized for acute illness may be at particularly elevated risk for post-discharge mortality. In this cross-sectional analysis, we measured the prevalence of stunting at hospital discharge and identified host, caregiver, and environmental correlates of stunting among children aged 1-59 months in Western Kenya enrolled in the Toto Bora Trial. Child age- and site-adjusted prevalence ratios were estimated using Poisson regression. Of the 1,394 children included in this analysis, 23% were stunted at hospital discharge. Older children (12-23 months and 24-59 months versus 0-5 months) had a higher prevalence of stunting (adjusted prevalence ratio [aPR]: 1.58; 95% CI: 1.04-2.36 and aPR: 1.59; 95% CI: 1.08-2.34, respectively). HIV-exposed, uninfected children (aPR: 1.94; 95% CI: 1.39-2.70), children with HIV infection (aPR: 2.73; 95% CI: 1.45-5.15), and those who were never exclusively breastfed in early life (aPR 2.51; 95% CI: 1.35-4.67) were more likely to be stunted. Caregiver education (primary school or less) and unimproved sanitation (pit latrine without slab floor or open defecation) were associated with increased risk of stunting (aPR: 1.94; 95% CI: 1.54-2.44; aPR: 1.99; 95% CI: 1.20-3.31; aPR: 3.57; 95% CI: 1.77-7.21, respectively). Hospital discharge represents an important opportunity for both identifying and delivering targeted interventions for nutrition-associated poor outcomes among a high-risk population of children.

The diagnosis and management of dehydration in children with wasting or nutritional edema: A systematic review

Dehydration is a major cause of death among children with wasting and diarrhea. We reviewed the evidence for the identification and management of dehydration among these children. Two systematic reviews were conducted to assess 1) the diagnostic performance of clinical signs or algorithms intended to measure dehydration, and 2) the efficacy and safety of low-osmolarity ORS versus ReSoMal on mortality, treatment failure, time to full rehydration, and electrolyte disturbances (management review). We searched PubMed/Medline, Embase, and Global Index Medicus for studies enrolling children 0-60 months old with wasting and diarrhea. The diagnostic review included four studies. Two studies found the Integrated Management of Childhood Illness (IMCI) and the Dehydration: Assessing Kids Accurately (DHAKA) algorithms had similar diagnostic performance, but both algorithms had high false positive rates for moderate (41% and 35%, respectively) and severe (76% and 82%, respectively) dehydration. One further IMCI algorithm study found a 23% false positive rate for moderate dehydration. The management review included six trials. One trial directly compared low osmolarity ORS to ReSoMal and found no difference in treatment failure rates, although ReSoMal had a shorter duration of treatment (16.1 vs. 19.6 hours, p = 0.036) and a higher incidence of hyponatremia. Both fluids failed to correct a substantial number of hypokalemia cases across studies. In conclusion, the IMCI dehydration assessment has comparable performance to other algorithms among wasted children. Low osmolarity ORS may be an alternative to ReSoMal for children with severe wasting, but might require additional potassium to combat hypokalemia.

Clinical and regulatory development strategies for Shigella vaccines intended for children younger than 5 years in low-income and middle-income countries

Shigellosis causes considerable public health burden, leading to excess deaths as well as acute and chronic consequences, particularly among children living in low-income and middle-income countries (LMICs). Several Shigella vaccine candidates are advancing in clinical trials and offer promise. Although multiple target populations might benefit from a Shigella vaccine, the primary strategic goal of WHO is to accelerate the development and accessibility of safe, effective, and affordable Shigella vaccines that reduce mortality and morbidity in children younger than 5 years living in LMICs. WHO consulted with regulators and policy makers at national, regional, and global levels to evaluate pathways that could accelerate regulatory approval in this priority population. Special consideration was given to surrogate efficacy biomarkers, the role of controlled human infection models, and the establishment of correlates of protection. A field efficacy study in children younger than 5 years in LMICs is needed to ensure introduction in this priority population.

Derivation and external validation of a clinical prognostic model identifying children at risk of death following presentation for diarrheal care

Diarrhea continues to be a leading cause of death for children under-five. Amongst children treated for acute diarrhea, mortality risk remains elevated during and after acute medical management. Identification of those at highest risk would enable better targeting of interventions, but available prognostic tools lack validation. We used clinical and demographic data from the Global Enteric Multicenter Study (GEMS) to build clinical prognostic models (CPMs) to predict death (in-treatment, after discharge, or either) in children aged ≤59 months presenting with moderate-to-severe diarrhea (MSD), in Africa and Asia. We screened variables using random forests, and assessed predictive performance with random forest regression and logistic regression using repeated cross-validation. We used data from the Kilifi Health and Demographic Surveillance System (KHDSS) and Kilifi County Hospital (KCH) in Kenya to externally validate our GEMS-derived CPM. Of 8060 MSD cases, 43 (0.5%) children died in treatment and 122 (1.5% of remaining) died after discharge. MUAC at presentation, respiratory rate, age, temperature, number of days with diarrhea at presentation, number of people living in household, number of children <60 months old living in household, and how much the child had been offered to drink since diarrhea started were predictive of death both in treatment and after discharge. Using a parsimonious 2-variable prediction model, we achieved an area under the ROC curve (AUC) of 0.84 (95% CI: 0.82, 0.86) in the derivation dataset, and an AUC = 0.74 (95% CI 0.71, 0.77) in the external dataset. Our findings suggest it is possible to identify children most likely to die after presenting to care for acute diarrhea. This could represent a novel and cost-effective way to target resources for the prevention of childhood mortality.

Plasmid-mediated quinolone resistance genes detected in Ciprofloxacin non-susceptible Escherichia coli and Klebsiella isolated from children under five years at hospital discharge, Kenya

BACKGROUND

The increasing spread of fluoroquinolone resistant enteric bacteria is a global public health concern. Children recently discharged from the hospital are at high risk of carriage of antimicrobial resistance (AMR) due to frequent exposure to antimicrobials during inpatient stays. This study aimed to determine the prevalence, correlates of ciprofloxacin (CIP) non-susceptibility, and distribution of plasmid-mediated quinolone resistance (PMQR) genes in Escherichia coli (E. coli) and Klebsiella spp isolated from children under five years being discharged from two Kenyan Hospitals.

METHODS

E. coli and Klebsiella spp were isolated from fecal samples from children discharged from hospital and subjected to antimicrobial susceptibility testing (AST) by disc diffusion and E-test. CIP non-susceptible isolates were screened for seven PMQR genes using multiplex polymerase chain reaction (PCR). Poisson regression was used to determine the association between the carriage of CIP non-susceptible isolates and patient characteristics.

RESULTS

Of the 280 CIP non-susceptible isolates: 188 E. coli and 92 Klebsiella spp isolates identified among 266 discharged children, 195 (68%) were CIP-non-susceptible with minimum inhibitory concentrations (MICs) of ≥ 1 µg/mL. Among these 195 isolates, 130 (67%) had high-level CIP MIC =  ≥ 32 µg/mL). Over 80% of the isolates had at least one PMQR gene identified: aac(6')lb-cr (60%), qnrB (24%), oqxAB (22%), qnrS (16%), and qepA (6%), however, qnrA was not identified in any isolates tested. Co-carriage of qnrB with acc(6')-lb-cr was the most predominant accounting for 20% of all the isolates. Ceftriaxone use during hospital admission and the presence of extended spectrum beta-lactamase (ESBL) production were significantly associated with the carriage of CIP non-susceptible E. coli and Klebsiella spp.

CONCLUSION

CIP non-susceptibility is common among E. coli and Klebsiella spp isolated from hospital discharged children in Kenya. Carriage and co-carriage of PMQR, including the newly identified qepA gene, were frequently observed. These findings suggest that children leaving the hospital may serve as an important reservoir for transmission of resistant E. coli and Klebsiella spp to the community. Enhanced surveillance for AMR determinants is critical to inform interventions to control antimicrobial-resistant bacteria.

Consequences of Shigella infection in young children: a systematic review

OBJECTIVES

We conducted a systematic review of the longitudinal consequences of Shigella infection in children to inform the value proposition for an effective vaccine.

METHODS

We searched PubMed and Embase for studies published from January 01, 1980 to December 12, 2022 and conducted in low- and middle-income countries that included longitudinal follow-up after Shigella detection among children aged <5 years, irrespective of language. We collected data on all outcomes subsequent to Shigella detection, except mortality.

RESULTS

Of 2627 papers identified, 52 met inclusion criteria. The median sample size of children aged <5 years was 66 (range 5-2172). Data were collected in 20 countries; 56% (n = 29) of the publications included Bangladesh. The most common outcomes related to diarrhea (n = 20), linear growth (n = 14), and the mean total cost of a Shigella episode (n = 4; range: $ 6.22-31.10). Among children with Shigella diarrhea, 2.9-61.1% developed persistent diarrhea (≥14 days); the persistence was significantly more likely among children who were malnourished, had bloody stool, or had multidrug-resistant Shigella. Cumulative Shigella infections over the first 2 years of life contributed to the greatest loss in length-for-age z-score.

CONCLUSION

We identified evidence that Shigella is associated with persistent diarrhea, linear growth faltering, and economic impact to the family.

Clinical prediction rule to guide diagnostic testing for Shigellosis and improve antibiotic stewardship for pediatric diarrhea

Background

Diarrheal diseases are a leading cause of death for children under-5. Identification of etiology helps guide pathogen-specific therapy, but availability of diagnostic testing is often limited in low resource settings. Our goal is to develop a clinical prediction rule (CPR) to guide clinicians in identifying when to use a point-of-care diagnostic for Shigella in children presenting with acute diarrhea.

Methods

We used clinical and demographic data from the Global Enteric Multicenter Study (GEMS) study to build predictive models for diarrhea of Shigella etiology in children ≤59 months presenting with moderate-to-severe diarrhea in Africa and Asia. We screened variables using random forests, and assessed predictive performance with random forest regression and logistic regression using cross-validation. We used the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study to externally validate our GEMS-derived CPR.

Results

Of the 5011 cases analyzed, 1332 (27%) had diarrhea of Shigella etiology. Our CPR had high predictive ability (AUC=0.80 (95% CI: 0.79, 0.81) using the top two predictive variables, age and caregiver reported bloody diarrhea. We show that by using our CPR to triage who receives diagnostic testing, 3 times more Shigella diarrhea cases would have been identified compared to current symptom-based guidelines, with only 27% of cases receiving a point-of-care diagnostic test.

Conclusions

We demonstrate how a clinical prediction rule can be used to guide use of a point-of-care diagnostic test for diarrhea management. Using our CPR, available diagnostic capacity can be optimized to improve appropriate antibiotic use.

Derivation and external validation of clinical prediction rules identifying children at risk of linear growth faltering

Background

Nearly 150 million children under-5 years of age were stunted in 2020. We aimed to develop a clinical prediction rule (CPR) to identify children likely to experience additional stunting following acute diarrhea, to enable targeted approaches to prevent this irreversible outcome.

Methods

We used clinical and demographic data from the Global Enteric Multicenter Study (GEMS) to build predictive models of linear growth faltering (decrease of ≥0.5 or ≥1.0 in height-for-age z-score [HAZ] at 60-day follow-up) in children ≤59 months presenting with moderate-to-severe diarrhea, and community controls, in Africa and Asia. We screened variables using random forests, and assessed predictive performance with random forest regression and logistic regression using fivefold cross-validation. We used the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study to (1) re-derive, and (2) externally validate our GEMS-derived CPR.

Results

Of 7639 children in GEMS, 1744 (22.8%) experienced severe growth faltering (≥0.5 decrease in HAZ). In MAL-ED, we analyzed 5683 diarrhea episodes from 1322 children, of which 961 (16.9%) episodes experienced severe growth faltering. Top predictors of growth faltering in GEMS were: age, HAZ at enrollment, respiratory rate, temperature, and number of people living in the household. The maximum area under the curve (AUC) was 0.75 (95% confidence interval [CI]: 0.75, 0.75) with 20 predictors, while 2 predictors yielded an AUC of 0.71 (95% CI: 0.71, 0.72). Results were similar in the MAL-ED re-derivation. A 2-variable CPR derived from children 0-23 months in GEMS had an AUC = 0.63 (95% CI: 0.62, 0.65), and AUC = 0.68 (95% CI: 0.63, 0.74) when externally validated in MAL-ED.

Conclusions

Our findings indicate that use of prediction rules could help identify children at risk of poor outcomes after an episode of diarrheal illness. They may also be generalizable to all children, regardless of diarrhea status.

Funding

This work was supported by the National Institutes of Health under Ruth L. Kirschstein National Research Service Award NIH T32AI055434 and by the National Institute of Allergy and Infectious Diseases (R01AI135114).

Brief Report: Performance of Tuberculosis Symptom Screening Among Hospitalized ART-Naive Children With HIV in Kenya

BACKGROUND

The World Health Organization (WHO) recommends tuberculosis (TB) diagnostic evaluation for children with HIV (CHIV) who have history of TB contact, poor weight gain, cough, or fever. These screening criteria were developed based on studies of symptomatic CHIV with incomplete microbiologic confirmation. We performed routine TB microbiologic evaluation of hospitalized CHIV with and without symptoms to develop a data-driven TB symptom screen.

METHODS

Among hospitalized antiretroviral therapy-naive Kenyan CHIV enrolled in the Pediatric Urgent Start of Highly Active Antiretroviral Therapy (PUSH) trial, we performed Xpert MTB/RIF and mycobacterial culture of respiratory and stool specimens independent of TB symptoms. We evaluated performance of WHO and other published pediatric TB screening criteria and derived optimized criteria using a combination of symptoms.

RESULTS

Of 168 CHIV who underwent TB microbiologic evaluation, 13 (8%) had confirmed TB. WHO TB symptom screening had 100% sensitivity and 4% specificity to detect confirmed TB. Published TB screening criteria that relied on prolonged symptoms missed cases of confirmed TB (sensitivity 85%-92%). An optimized symptom screen including weight loss, cough, anorexia, or TB contact had 100% sensitivity and improved specificity (31%) compared with the WHO pediatric TB symptom screen.

CONCLUSIONS

The WHO TB symptom screen was highly sensitive but resulted in a high proportion of hospitalized CHIV who would require TB diagnostic evaluation. Other published TB screening criteria missed CHIV with confirmed TB. Our optimized screening tool increased specificity while preserving sensitivity. Future multicenter studies are needed to improve TB screening tools for CHIV in both inpatient and outpatient settings.

Cytomegalovirus Viremia Predicts Postdischarge Mortality in Kenyan HIV-Exposed Uninfected Children

BACKGROUND

Cytomegalovirus (CMV) viremia is associated with mortality in severely ill immunocompetent adults and hospitalized children with HIV (CWH). We measured CMV viremia in HIV-exposed and -unexposed Kenyan children aged 1-59 months discharged from hospital and determined its relationship with postdischarge mortality.

METHODS

CMV DNA levels were measured in plasma from 1024 children (97 of which were HIV exposed uninfected [HEU], and 15 CWH). Poisson and Cox proportional hazards regression models were used to identify correlates of CMV viremia ≥ 1000 IU/mL 
and estimate associations with 6-month mortality, respectively.

RESULTS

CMV viremia was detected in 31% of children, with levels ≥ 1000 IU/mL in 5.8%. HIV infection, age < 2 years, breastfeeding, and midupper arm circumference < 12.5 cm were associated with CMV viremia ≥ 1000 IU/mL. Among HEU children, CMV ≥ 1000 IU/mL (hazard ratio [HR] = 32.0; 95% confidence interval [CI], 2.9-354.0; P = .005) and each 1-log increase in CMV viral load (HR = 5.04; 95% CI, 1.7-14.6; P = .003) were associated with increased risk of mortality. CMV viremia was not significantly associated with mortality in HIV-unexposed children.

CONCLUSIONS

CMV levels at hospital postdischarge predict increased risk of 6-month mortality in Kenyan HEU children. CMV suppression may be a novel target to reduce mortality in HEU children.

CLINICAL TRIAL REGISTRATION

NCT02414399.

The Role of Food Insecurity and Dietary Diversity on Recovery from Wasting among Hospitalized Children Aged 6-23 Months in Sub-Saharan Africa and South Asia

Background: Current guidelines for the management of childhood wasting primarily focus on the provision of therapeutic foods and the treatment of medical complications. However, many children with wasting live in food-secure households, and multiple studies have demonstrated that the etiology of wasting is complex, including social, nutritional, and biological causes. We evaluated the contribution of household food insecurity, dietary diversity, and the consumption of specific food groups to the time to recovery from wasting after hospital discharge. Methods: We conducted a secondary analysis of the Childhood Acute Illness Network (CHAIN) cohort, a multicenter prospective study conducted in six low- or lower-middle-income countries. We included children aged 6−23 months with wasting (mid-upper arm circumference [MUAC] ≤ 12.5 cm) or kwashiorkor (bipedal edema) at the time of hospital discharge. The primary outcome was time to nutritional recovery, defined as a MUAC > 12.5 cm without edema. Using Cox proportional hazards models adjusted for age, sex, study site, HIV status, duration of hospitalization, enrollment MUAC, referral to a nutritional program, caregiver education, caregiver depression, the season of enrollment, residence, and household wealth status, we evaluated the role of reported food insecurity, dietary diversity, and specific food groups prior to hospitalization on time to recovery from wasting during the 6 months of posthospital discharge. Findings: Of 1286 included children, most participants (806, 63%) came from food-insecure households, including 170 (13%) with severe food insecurity, and 664 (52%) participants had insufficient dietary diversity. The median time to recovery was 96 days (18/100 child-months (95% CI: 17.0, 19.0)). Moderate (aHR 1.17 [0.96, 1.43]) and severe food insecurity (aHR 1.14 [0.88, 1.48]), and insufficient dietary diversity (aHR 1.07 [0.91, 1.25]) were not significantly associated with time to recovery. Children who had consumed legumes and nuts prior to diagnosis had a quicker recovery than those who did not (adjusted hazard ratio (aHR): 1.21 [1.01,1.44]). Consumption of dairy products (aHR 1.13 [0.96, 1.34], p = 0.14) and meat (aHR 1.11 [0.93, 1.33]), p = 0.23) were not statistically significantly associated with time to recovery. Consumption of fruits and vegetables (aHR 0.78 [0.65,0.94]) and breastfeeding (aHR 0.84 [0.71, 0.99]) before diagnosis were associated with longer time to recovery. Conclusion: Among wasted children discharged from hospital and managed in compliance with wasting guidelines, food insecurity and dietary diversity were not major determinants of recovery.

Pivotal Shigella Vaccine Efficacy Trials-Study Design Considerations from a Shigella Vaccine Trial Design Working Group

Vaccine candidates for Shigella are approaching phase 3 clinical trials in the target population of young children living in low- and middle-income countries. Key study design decisions will need to be made to maximize the success of such trials and minimize the time to licensure and implementation. We convened an ad hoc working group to identify the key aspects of trial design that would meet the regulatory requirements to achieve the desired indication of prevention of moderate or severe shigellosis due to strains included in the vaccine. The proposed primary endpoint of pivotal Shigella vaccine trials is the efficacy of the vaccine against the first episode of acute moderate or severe diarrhea caused by the Shigella strains contained within the vaccine. Moderate or severe shigellosis could be defined by a modified Vesikari score with dysentery and molecular detection of vaccine-preventable Shigella strains. This report summarizes the rationale and current data behind these considerations, which will evolve as new data become available and after further review and consultation by global regulators and policymakers.

Antimicrobial resistance including Extended Spectrum Beta Lactamases (ESBL) among E. coli isolated from kenyan children at hospital discharge

Background

Children who have been discharged from hospital in sub-Saharan Africa remain at substantial risk of mortality in the post-discharge period. Antimicrobial resistance (AMR) may be an important factor. We sought to determine the prevalence and risk factors associated with AMR in commensal Escherichia coli(E. coli) from Kenyan children at the time of discharge.

Methodology/Principle findings

Fecal samples were collected from 406 children aged 1–59 months in western Kenya at the time of discharge from hospital and cultured for E. coli. Susceptibility to ampicillin, ceftriaxone, cefotaxime, ceftazidime, cefoxitin, imipenem, ciprofloxacin, gentamicin, combined amoxicillin/clavulanic acid, trimethoprim-sulfamethoxazole, azithromycin, and chloramphenicol was determined by disc diffusion according to guidelines from the Clinical and Laboratory Standards Institute (CLSI). Poisson regression was used to determine associations between participant characteristics and the presence of extended-spectrum beta-lactamases (ESBL) producing E. coli. Non-susceptibility to ampicillin (95%), gentamicin (44%), ceftriaxone (46%), and the presence of ESBL (44%) was high. Receipt of antibiotics during the hospitalization was associated with the presence of ESBL (aPR = 2.23; 95% CI: 1.29–3.83) as was being hospitalized within the prior year (aPR = 1.32 [1.07–1.69]). Open defecation (aPR = 2.02; 95% CI: 1.39–2.94), having a toilet shared with other households (aPR = 1.49; 95% CI: 1.17–1.89), and being female (aPR = 1.42; 95% CI: 1.15–1.76) were associated with carriage of ESBL E. coli

Conclusions/Significance

AMR is common among isolates of E. coli from children at hospital discharge in Kenya, including nearly half having detectable ESBL.

Children who have been hospitalized in sub-Saharan Africa remain at a high risk of death and morbidity for at least 6 months following discharge. These children may harbor AMR in commensal bacteria following hospitalization, which may be associated with poor outcomes. There are limited data describing AMR and risk factors that are associated with AMR carriage at hospital discharge. In this cross-sectional study of Kenyan children under 5 years of age discharged from hospitals, we found AMR to be high. Children who received antibiotics in the hospital, had limited access to improved sanitation, and who were female had the highest prevalence of ESBL-producing E. coli.

World Health Organization Expert Working Group: Recommendations for assessing morbidity associated with enteric pathogens

BACKGROUND

Diarrhoeal infections are one of the leading causes of child's mortality and morbidity. Vaccines against Shigella, enterotoxigenic E. coli (ETEC), norovirus and invasive non-typhoidal Salmonella are in clinical development, however, their full value in terms of short and long-term health and socio-economic burden needs to be evaluated and communicated, to rationalise investment in vaccine development, and deployment. While estimates of mortality of enteric infections exist, the long-term morbidity estimates are scarce and have not been systematically collected.

METHODS

The World Health Organization (WHO) has convened a Burden of Enteric Diseases Morbidity Working Group (BoED MWG) who identified key workstreams needed to characterise the morbidity burden of enteric infections. The group also identified four criteria for the prioritisation of pathogens of which impact on long-term morbidity needs to be assessed.

RESULTS

The BoED MWG suggested to identify and analyse the individual level data from historical datasets to estimate the impact of enteric infections and confounders on long-term morbidity, including growth faltering and cognitive impairment in children (workstream 1); to conduct a systematic review of evidence on the association of aetiology specific diarrhoea with short- and long- term impact on growth, including stunting, and possibly cognitive impairment in children, while accounting for potential confounders (workstream 2); and to conduct a systematic review of evidence on the association of aetiology specific diarrhoea with short- and long- term impact on health outcomes in adults. The experts prioritised four pathogens for this work: Campylobacter jejuni, ETEC (LT or ST), norovirus (G1 or G2), and Shigella (dysenteriae, flexneri, sonnei).

CONCLUSIONS

The proposed work will contribute to improving the understanding of the impact of enteric pathogens on long-term morbidity. The timing of this work is critical as all four pathogens have vaccine candidates in the clinical pipeline and decisions about investments in development, manufacturing or vaccine procurement and use are expected to be made soon.

Effect of 3 Days of Oral Azithromycin on Young Children With Acute Diarrhea in Low-Resource Settings: A Randomized Clinical Trial

Importance

World Health Organization (WHO) guidelines do not recommend routine antibiotic use for children with acute watery diarrhea. However, recent studies suggest that a significant proportion of such episodes have a bacterial cause and are associated with mortality and growth impairment, especially among children at high risk of diarrhea-associated mortality. Expanding antibiotic use among dehydrated or undernourished children may reduce diarrhea-associated mortality and improve growth.

Objective

To determine whether the addition of azithromycin to standard case management of acute nonbloody watery diarrhea for children aged 2 to 23 months who are dehydrated or undernourished could reduce mortality and improve linear growth.

Design, Setting, and Participants

The Antibiotics for Children with Diarrhea (ABCD) trial was a multicountry, randomized, double-blind, clinical trial among 8266 high-risk children aged 2 to 23 months presenting with acute nonbloody diarrhea. Participants were recruited between July 1, 2017, and July 10, 2019, from 36 outpatient hospital departments or community health centers in a mixture of urban and rural settings in Bangladesh, India, Kenya, Malawi, Mali, Pakistan, and Tanzania. Each participant was followed up for 180 days. Primary analysis included all randomized participants by intention to treat.

Interventions

Enrolled children were randomly assigned to receive either oral azithromycin, 10 mg/kg, or placebo once daily for 3 days in addition to standard WHO case management protocols for the management of acute watery diarrhea.

Main Outcomes and Measures

Primary outcomes included all-cause mortality up to 180 days after enrollment and linear growth faltering 90 days after enrollment.

Results

A total of 8266 children (4463 boys [54.0%]; mean [SD] age, 11.6 [5.3] months) were randomized. A total of 20 of 4133 children in the azithromycin group (0.5%) and 28 of 4135 children in the placebo group (0.7%) died (relative risk, 0.72; 95% CI, 0.40-1.27). The mean (SD) change in length-for-age z scores 90 days after enrollment was -0.16 (0.59) in the azithromycin group and -0.19 (0.60) in the placebo group (risk difference, 0.03; 95% CI, 0.01-0.06). Overall mortality was much lower than anticipated, and the trial was stopped for futility at the prespecified interim analysis.

Conclusions and Relevance

The study did not detect a survival benefit for children from the addition of azithromycin to standard WHO case management of acute watery diarrhea in low-resource settings. There was a small reduction in linear growth faltering in the azithromycin group, although the magnitude of this effect was not likely to be clinically significant. In low-resource settings, expansion of antibiotic use is not warranted. Adherence to current WHO case management protocols for watery diarrhea remains appropriate and should be encouraged.

Trial Registration

ClinicalTrials.gov Identifier: NCT03130114.

Azithromycin for the prevention of rehospitalisation and death among Kenyan children being discharged from hospital: a double-blind, placebo-controlled, randomised controlled trial

BACKGROUND

Mass drug administration of azithromycin to children in sub-Saharan Africa has been shown to improve survival in high-mortality settings. The period after hospital discharge is a time of elevated risk unaddressed by current interventions and might provide an opportunity for targeting empirical azithromycin administration. We aimed to assess the efficacy of azithromycin administered at hospital discharge on risk of death and rehospitalisation in Kenyan children younger than 5 years.

METHODS

In this double-blind, placebo-controlled randomised trial, children were randomly assigned (1:1) to receive a 5-day course of azithromycin (oral suspension 10 mg/kg on day 1, followed by 5mg/kg per day on days 2-5) or identically appearing and tasting placebo at discharge from four hospitals in western Kenya. Children were eligible if they were aged 1-59 months at hospital discharge, weighed at least 2 kg, and had been admitted to hospital for any medical reason other than trauma, poisoning, or congenital anomaly. The primary outcome was death or rehospitalisation in the subsequent 6-month period in a modified intention-to-treat population, compared by randomisation group with Cox proportional hazards regression and Kaplan-Meier. Azithromycin resistance in Escherichia coli isolates from a random subset of children was compared by randomisation group with generalised estimating equations. This trial is registered with ClinicalTrials.gov, NCT02414399.

FINDINGS

Between June 28, 2016, and Nov 4, 2019, 1400 children were enrolled in the trial at discharge from hospital, with 703 (50·2%) randomly assigned to azithromycin and 697 (49·8%) to placebo. Among the 1398 children included in the modified intention-to-treat analysis (702 in the azithromycin group and 696 in the placebo group), the incidence of death or rehospitalisation was 20·4 per 100 child-years in the azithromycin group and 22·5 per 100 child-years in the placebo group (adjusted hazard ratio 0·91, 95·5% CI 0·64-1·29, p=0·58). Azithromycin resistance was common in commensal E coli isolates from enrolled children before randomisation (37·7% of 406 isolates) despite only 3·7% of children having received a macrolide antibiotic during the hospitalisation. Azithromycin resistance was slightly higher at 3 months after randomisation in the azithromycin group (26·9%) than in the placebo group (19·1%; adjusted prevalence ratio 1·41, 95% CI 0·95-2·09, p=0·088), with no difference observed at 6 months (1·17, 0·78-1·76, p=0·44).

INTERPRETATION

We did not observe a significant benefit of a 5-day course of azithromycin delivered to children younger than 5 years at hospital discharge despite the overall high risk of mortality and rehospitalisation. These findings highlight the need for more research into mechanisms and interventions for prevention of morbidity and mortality in the post-discharge period.

FUNDING

Eunice Kennedy Shriver National Institute of Child Health & Human Development.

The Clinical Presentation of Culture-positive and Culture-negative, Quantitative Polymerase Chain Reaction (qPCR)-Attributable Shigellosis in the Global Enteric Multicenter Study and Derivation of a Shigella Severity Score: Implications for Pediatric Shigella Vaccine Trials

BACKGROUND

Shigella is a leading cause of childhood diarrhea and target for vaccine development. Microbiologic and clinical case definitions are needed for pediatric field vaccine efficacy trials.

METHODS

We compared characteristics of moderate to severe diarrhea (MSD) cases in the Global Enteric Multicenter Study (GEMS) between children with culture positive Shigella to those with culture-negative, quantitative polymerase chain reaction (qPCR)-attributable Shigella (defined by an ipaH gene cycle threshold <27.9). Among Shigella MSD cases, we determined risk factors for death and derived a clinical severity score.

RESULTS

Compared to culture-positive Shigella MSD cases (n = 745), culture-negative/qPCR-attributable Shigella cases (n = 852) were more likely to be under 12 months, stunted, have a longer duration of diarrhea, and less likely to have high stool frequency or a fever. There was no difference in dehydration, hospitalization, or severe classification from a modified Vesikari score. Twenty-two (1.8%) Shigella MSD cases died within the 14-days after presentation to health facilities, and 59.1% of these deaths were in culture-negative cases. Age <12 months, diarrhea duration prior to presentation, vomiting, stunting, wasting, and hospitalization were associated with mortality. A model-derived score assigned points for dehydration, hospital admission, and longer diarrhea duration but was not significantly better at predicting 14-day mortality than a modified Vesikari score.

CONCLUSIONS

A composite severity score consistent with severe disease or dysentery may be a pragmatic clinical endpoint for severe shigellosis in vaccine trials. Reliance on culture for microbiologic confirmation may miss a substantial number of Shigella cases but is currently required to measure serotype specific immunity.

Prevalence and Correlates of Cryptosporidium Infections in Kenyan Children With Diarrhea and Their Primary Caregivers

BACKGROUND

Cryptosporidium is a leading cause of diarrhea in Sub-Saharan Africa and is associated with substantial morbidity and mortality in young children.

METHODS

  We analyzed data from children aged 6-71 months presenting to 2 public hospitals in Western Kenya with acute diarrhea and their primary caregivers, including detection of Cryptosporidium by quantitative polymerase chain reaction (PCR) and immunoassay analysis in stool samples from both children and their caregivers. Associations between potential transmission sources and child/caregiver Cryptosporidium infection were evaluated using prevalence ratios (PRs). Secondary analyses evaluated host and clinical risk factors of child/caregiver Cryptosporidium infection.

RESULTS

Among 243 child-caregiver pairs enrolled, 77 children (32%) and 57 caregivers (23%) had Cryptosporidium identified by either immunoassay or PCR. Twenty-six of the 243 child-caregiver pairs (11%) had concordant detection of Cryptosporidium. Cryptosporidium infection in children was associated with detection of Cryptosporidium in caregivers (adjusted PR [aPR], 1.8; 95% CI, 1.2 to 2.6; P = .002) and unprotected water source (aPR, 2.0; 95% CI, 1.3 to 3.2; P = .003). Risk factors for Cryptosporidium detection in caregivers included child Cryptosporidium infection (aPR, 2.0; 95% CI, 1.3 to 3.0; P = .002) as well as cow (aPR, 3.1; 95% CI, 1.4 to 7.0; P = .02) and other livestock ownership (aPR, 2.6; 95% CI, 1.1 to 6.3; P = .03) vs no livestock ownership. Recent diarrhea in caregivers and children was independently associated with child and caregiver Cryptosporidium infections, respectively.

CONCLUSIONS

Our results are consistent with the hypothesis that Cryptosporidium transmission can occur directly between child-caregiver dyads as well as through other pathways involving water and livestock. Additional research into caregivers as a source of childhood Cryptosporidium infection is warranted.

Examining the relationship between diarrhea and linear growth in Kenyan HIV-exposed, uninfected infants

BACKGROUND

Diarrhea in infancy can compromise linear growth and this relationship is likely influenced by diarrhea severity, number of episodes, and the timing of those episodes. HIV exposed, uninfected infants (HEU) have higher risk of growth faltering, infectious morbidity and mortality than HIV-unexposed infants and may be representative of children particularly vulnerable to diarrhea-associated linear growth faltering.

METHODOLOGY/PRINCIPAL FINDINGS

We utilized data from a cohort of Kenyan HEU infants followed from birth to 12 months of age. Infant length and morbidity were ascertained at monthly study visits and sick visits. Longitudinal models estimated the association between diarrhea severity and length-for-age Z-score (LAZ) in the following month, at 12 months of age, and in 6-month intervals. The 372 enrolled infants experienced an average of 2.15 episodes (range: 0-8) of diarrhea and 0.54 episodes (0-4) of moderate-to-severe diarrhea (MSD) between birth and 12 months. Surviving infants had a mean LAZ of -0.97 (standard deviation: 1.2) at 12 months. MSD was significantly associated with an average loss of 0.14 (95% Confidence Interval [CI]: -0.24, -0.05, p = 0.003) in LAZ one month after the episode. Linear growth outcomes were not predicted by cumulative episodes of diarrhea, or timing of diarrhea during infancy.

CONCLUSIONS/SIGNIFICANCE

Diarrhea severity influenced the relationship between diarrhea and subsequent linear growth. HEU infants with MSD may benefit from nutritional interventions following severe diarrhea to protect against linear growth faltering.

The effect of acute malnutrition on enteric pathogens, moderate-to-severe diarrhoea, and associated mortality in the Global Enteric Multicenter Study cohort: a post-hoc analysis

Background

Host vulnerabilities associated with acute malnutrition could facilitate the ability of specific enteric pathogens to cause diarrhoea and associated mortality. Using data from the Global Enteric Multicenter Study, we assessed whether acute malnutrition modifies the association between common enteric pathogens and moderate-to-severe diarrhoea, and whether associations between enteric pathogens and death were modified by acute malnutrition.

Methods

Children with moderate-to-severe diarrhoea and age-matched and community-matched controls were included in this post-hoc analysis if their mid-upper arm circumference had been measured and if they were older than 6 months of age. Acute malnutrition was defined as mid-upper arm circumference below 12·5 cm, capturing both severe acute malnutrition (<11·5 cm) and moderate acute malnutrition (≥11·5 cm and <12·5 cm). We tested whether acute malnutrition modified associations between enteric pathogens and moderate-to-severe diarrhoea in conditional logistic regression models. Among children with moderate-to-severe diarrhoea, Cox proportional hazards regression evaluated the modifying effect of acute malnutrition on the relationship between pathogens and 60-day fatality rate.

Findings

The age, site, and co-infection adjusted odds ratios (aORs) for moderate-to-severe diarrhoea associated with typical enteropathogenic Escherichia coli among children aged 6–11 months was 2·08 (95% CI 1·14–3·79) in children with acute malnutrition, and 0·97 (0·77–1·23) in children with better nutritional status, compared with healthy controls. Enterotoxigenic E coli producing heat-stable toxin among children aged 12–23 months also had a stronger association with moderate-to-severe diarrhoea in children with acute malnutrition (aOR 7·60 [2·63–21·95]) than among similarly aged children with better nutritional status (aOR 2·39 [1·76–3·25]). Results for Shigella spp, norovirus, and sapovirus suggested they had a stronger association with moderate-to-severe diarrhoea than other pathogens among children with better nutritional status, although Shigella spp remained associated with moderate-to-severe diarrhoea in both nutritional groups. 92 (64%) of 144 children with moderate-to-severe diarrhoea who died had acute malnutrition. Pathogen-specific 60-day fatality rates for all pathogens were higher among children with acute malnutrition, but no individual pathogen had a significantly larger increase in its relative association with mortality.

Interpretation

Acute malnutrition might strengthen associations between specific pathogens and moderate-to-severe diarrhoea. However, the strong link between acute malnutrition and mortality during moderate-to-severe diarrhoea in children is not limited to specific infections, and affects a broad spectrum of enteric pathogens. Interventions addressing acute malnutrition could be an effective way to lower the mortality of both childhood malnutrition and diarrhoea.

Funding

The Bill & Melinda Gates Foundation.

Maternal Diarrhea and Antibiotic Use are Associated with Increased Risk of Diarrhea among HIV-Exposed, Uninfected Infants in Kenya

HIV-exposed, uninfected (HEU) children are a growing population at particularly high risk of infection-related death in whom preventing diarrhea may significantly reduce under-5 morbidity and mortality in sub-Saharan Africa. A historic cohort (1999-2002) of Kenyan HEU infants followed from birth to 12 months was used. Maternal and infant morbidity were ascertained at monthly clinic visits and unscheduled sick visits. The Andersen-Gill Cox model was used to assess maternal, environmental, and infant correlates of diarrhea, moderate-to-severe diarrhea (MSD; diarrhea with dehydration, dysentery, or related hospital admission), and prolonged/persistent diarrhea (> 7 days) in infants. HIV-exposed, uninfected infants (n = 373) experienced a mean 2.09 (95% CI: 1.93, 2.25) episodes of diarrhea, 0.47 (95% CI: 0.40, 0.55) episodes of MSD, and 0.34 (95% CI: 0.29, 0.42) episodes of prolonged/persistent diarrhea in their first year. Postpartum maternal diarrhea was associated with increased risk of infant diarrhea (Hazard ratio [HR]: 2.09; 95% CI: 1.43, 3.06) and MSD (HR: 2.89; 95% CI: 1.10, 7.59). Maternal antibiotic use was a risk factor for prolonged/persistent diarrhea (HR: 1.63; 95% CI: 1.04, 2.55). Infants living in households with a pit latrine were 1.44 (95% CI: 1.19, 1.74) and 1.49 (95% CI: 1.04, 2.14) times more likely to experience diarrhea and MSD, respectively, relative to those with a flush toilet. Current exclusive breastfeeding was protective against MSD (HR: 0.30; 95% CI: 0.15, 0.58) relative to infants receiving no breast milk. Reductions in maternal diarrhea may result in substantial reductions in diarrhea morbidity among HEU children, in addition to standard diarrhea prevention interventions.

Projected impact and cost-effectiveness of community-based versus targeted azithromycin administration strategies for reducing child mortality in sub-Saharan Africa

BACKGROUND

Trials of mass drug administration (MDA) of azithromycin (AZM) report reductions in child mortality in sub-Saharan Africa (SSA). AZM targeted to high-risk children may preserve benefit while minimizing antibiotic exposure. We modeled the cost-effectiveness of MDA to children 1-59 months of age, MDA to children 1-5 months of age, AZM administered at hospital discharge, and the combination of MDA and post-discharge AZM.

METHODS AND FINDINGS

Models employed a payer perspective with a 1-year time horizon. Cost-effectiveness was presented as cost per DALY averted and death averted, with probabilistic sensitivity analyses. The model included parameters for macrolide resistance, adverse events, hospitalization, and mortality sourced from published data. Assuming a base-case 1.64% mortality risk among children 1-59 months old, 3.1% among children 1-5 months old, 4.4% mortality risk post-discharge, and 13.5% mortality reduction per trial data, post-discharge AZM would avert ~45,000 deaths, at a cost of $2.84/DALY (95% uncertainty interval [UI]: 1.71-5.57) averted. MDA to only children 1-5 months old would avert ~186,000 deaths at a cost of $4.89/DALY averted (95% UI: 2.88-11.42), MDA to all under-5 children would avert ~267,000 deaths a cost of $14.26/DALY averted (95% UI: 8.72-27.08). Cost-effectiveness decreased with presumed diminished efficacy due to macrolide resistance.

CONCLUSIONS

Targeting AZM to children at highest risk of death may be an antibiotic-sparing and cost-effective, or even cost-saving, strategy to reduce child mortality. However, targeted AZM averts fewer absolute deaths and may not reach all children who would benefit. Any AZM administration decision must consider implications for antibiotic resistance.

Determinants of linear growth faltering among children with moderate-to-severe diarrhea in the Global Enteric Multicenter Study

BACKGROUND

Moderate-to-severe diarrhea (MSD) in the first 2 years of life can impair linear growth. We sought to determine risk factors for linear growth faltering and to build a clinical prediction tool to identify children most likely to experience growth faltering following an episode of MSD.

METHODS

Using data from the Global Enteric Multicenter Study of children 0-23 months old presenting with MSD in Africa and Asia, we performed log-binomial regression to determine clinical and sociodemographic factors associated with severe linear growth faltering (loss of ≥ 0.5 length-for-age z-score [LAZ]). Linear regression was used to estimate associations with ΔLAZ. A clinical prediction tool was developed using backward elimination of potential variables, and Akaike Information Criterion to select the best fit model.

RESULTS

Of the 5902 included children, mean age was 10 months and 43.2% were female. Over the 50-90-day follow-up period, 24.2% of children had severe linear growth faltering and the mean ΔLAZ over follow-up was - 0.17 (standard deviation [SD] 0.54). After adjustment for age, baseline LAZ, and site, several factors were associated with decline in LAZ: young age, acute malnutrition, hospitalization at presentation, non-dysenteric diarrhea, unimproved sanitation, lower wealth, fever, co-morbidity, or an IMCI danger sign. Compared to children 12-23 months old, those 0-6 months were more likely to experience severe linear growth faltering (adjusted prevalence ratio [aPR] 1.97 [95% CI 1.70, 2.28]), as were children 6-12 months of age (aPR 1.72 [95% CI 1.51, 1.95]). A prediction model that included age, wasting, stunting, presentation with fever, and presentation with an IMCI danger sign had an area under the ROC (AUC) of 0.67 (95% CI 0.64, 0.69). Risk scores ranged from 0 to 37, and a cut-off of 21 maximized sensitivity (60.7%) and specificity (63.5%).

CONCLUSION

Younger age, acute malnutrition, MSD severity, and sociodemographic factors were associated with short-term linear growth deterioration following MSD. Data routinely obtained at MSD may be useful to predict children at risk for growth deterioration who would benefit from interventions.

Birth size and early pneumonia predict linear growth among HIV-exposed uninfected infants

Stunting remains a global health priority, particularly in sub-Saharan Africa. Identifying determinants of linear growth in HIV-exposed uninfected (HEU) infants can inform interventions to prevent stunting in this vulnerable population. HIV-infected mothers and their uninfected infants were followed monthly from pregnancy to 12-month post-partum in Nairobi, Kenya. Mixed-effects models estimated the change in length-for-age z-score (LAZ) from birth to 12 months by environmental, maternal, and infant characteristics. Multivariable models included factors univariately associated with LAZ. Among 372 HEU infants, mean LAZ decreased from -0.54 (95% confidence interval [CI] [-0.67, -0.41]) to -1.09 (95% CI [-1.23, -0.96]) between 0 and 12 months. Declines in LAZ were associated with crowding (≥2 persons per room; adjusted difference [AD] in 0-12 month change: -0.46; 95% CI [-0.87, -0.05]), use of a pit latrine versus a flush toilet (AD: -0.29; 95% CI [-0.57, -0.02]), and early infant pneumonia (AD: -1.14; 95% CI [-1.99, -0.29]). Infants with low birthweight (<2,500 g; AD: 1.08; 95% CI [0.40, 1.76]) and birth stunting (AD: 1.11; 95% CI [0.45, 1.78]) experienced improved linear growth. By 12 months of age, 46 infants were stunted, of whom 11 (24%) were stunted at birth. Of the 34 infants stunted at birth with an available 12-month LAZ, 68% were not stunted at 12 months. Some low birthweight and birth-stunted HEU infants had significant linear growth recovery. Early infant pneumonia and household environment predicted poor linear growth and may identify a subgroup of HEU infants for whom to provide growth-promoting interventions.

Morbidity and mortality due to shigella and enterotoxigenic Escherichia coli diarrhoea: the Global Burden of Disease Study 1990-2016

Background

Shigella and enterotoxigenic Escherichia coli (ETEC) are bacterial pathogens that are frequently associated with diarrhoeal disease, and are a significant cause of mortality and morbidity worldwide. The Global Burden of Diseases, Injuries, and Risk Factors study 2016 (GBD 2016) is a systematic, scientific effort to quantify the morbidity and mortality due to over 300 causes of death and disability. We aimed to analyse the global burden of shigella and ETEC diarrhoea according to age, sex, geography, and year from 1990 to 2016.

Methods

We modelled shigella and ETEC-related mortality using a Bayesian hierarchical modelling platform that evaluates a wide range of covariates and model types on the basis of vital registration and verbal autopsy data. We used a compartmental meta-regression tool to model the incidence of shigella and ETEC, which enforces an association between incidence, prevalence, and remission on the basis of scientific literature, population representative surveys, and health-care data. We calculated 95% uncertainty intervals (UIs) for the point estimates.

Findings

Shigella was the second leading cause of diarrhoeal mortality in 2016 among all ages, accounting for 212 438 deaths (95% UI 136 979–326 913) and about 13·2% (9·2–17·4) of all diarrhoea deaths. Shigella was responsible for 63 713 deaths (41 191–93 611) among children younger than 5 years and was frequently associated with diarrhoea across all adult age groups, increasing in elderly people, with broad geographical distribution. ETEC was the eighth leading cause of diarrhoea mortality in 2016 among all age groups, accounting for 51 186 deaths (26 757–83 064) and about 3·2% (1·8–4·7) of diarrhoea deaths. ETEC was responsible for about 4·2% (2·2–6·8) of diarrhoea deaths in children younger than 5 years.

Interpretation

The health burden of bacterial diarrhoeal pathogens is difficult to estimate. Despite existing prevention and treatment options, they remain a major cause of morbidity and mortality globally. Additional emphasis by public health officials is needed on a reduction in disease due to shigella and ETEC to reduce disease burden.

Funding

Bill & Melinda Gates Foundation.

Urine Tuberculosis Lipoarabinomannan Predicts Mortality in Hospitalized Human Immunodeficiency Virus-Infected Children

Clinical Trials Registration

NCT02063880.

Interventions to reduce post-acute consequences of diarrheal disease in children: a systematic review

BACKGROUND

Although acute diarrhea often leads to acute dehydration and electrolyte imbalance, children with diarrhea also suffer long term morbidity, including recurrent or prolonged diarrhea, loss of weight, and linear growth faltering. They are also at increased risk of post-acute mortality. The objective of this systematic review was to identify interventions that address these longer term consequences of diarrhea.

METHODS

We searched Medline for randomized controlled trials (RCTs) of interventions conducted in low- and middle-income countries, published between 1980 and 2016 that included children under 15 years of age with diarrhea and follow-up of at least 7 days. Effect measures were summarized by intervention. PRISMA guidelines were followed.

RESULTS

Among 314 otherwise eligible RCTs, 65% were excluded because follow-up did not extend beyond 7 days. Forty-six trials were included, the majority of which (59%) were conducted in Southeast Asia (41% in Bangladesh alone). Most studies were small, 76% included less than 200 participants. Interventions included: therapeutic zinc alone (28.3%) or in combination with vitamin A (4.3%), high protein diets (19.6%), probiotics (10.9%), lactose free diets (10.9%), oral rehydration solution (ORS) formulations (8.7%), dietary supplements (6.5%), other dietary interventions (6.5%), and antimicrobials (4.3%). Prolonged or recurrent diarrhea was the most commonly reported outcome, and was assessed in ORS, probiotic, vitamin A, and zinc trials with no consistent benefit observed. Seven trials evaluated mortality, with follow-up times ranging from 8 days to 2 years. Only a single trial found a mortality benefit (therapeutic zinc). There were mixed results for dietary interventions affecting growth and diarrhea outcomes in the post-acute period.

CONCLUSION

Despite the significant post-acute mortality and morbidity associated with diarrheal episodes, there is sparse evidence evaluating the effects of interventions to decrease these sequelae. Adequately powered trials with extended follow-up are needed to identify effective interventions to prevent post-acute diarrhea outcomes.

Mycobacterium tuberculosis bacteremia in adults and children: a systematic review and meta-analysis

SETTINGp: Among human immunodeficiency virus (HIV) infected adults living in tuberculosis (TB) endemic settings, Mycobacterium tuberculosis is a common cause of bloodstream infections. Although young children have an increased propensity for M. tuberculosis dissemination, M. tuberculosis bacteremia is infrequently described in children.

OBJECTIVE

To determine the prevalence of M. tuberculosis bacteremia in adult and pediatric patients and to examine sources of heterogeneity between estimates.

DESIGN

Systematic review and meta-analysis.

RESULTS

Of 1077 reviewed abstracts, 27 publications met the inclusion criteria, yielding 29 independent M. tuberculosis bacteremia prevalence estimates: 22 in adults, 6 in children, and 1 not stratified by age group. The random effects pooled M. tuberculosis bacteremia prevalence in adults was 13.5% (95%CI 10.8-16.2) and 0.4% (95%CI 0-0.9) in children (P for difference = 0.004). Restricting analyses to HIV-infected participants, pooled M. tuberculosis bacteremia prevalence from 21 adult studies was 15.5% (95%CI 12.5-18.5) and 0.8% (95%CI 0-1.8) in three pediatric studies (P = 0.001). Inclusion of pre-determined study-level confounders did not account for observed differences in M. tuberculosis bacteremia prevalence between age groups.

CONCLUSION

While M. tuberculosis bacteremia appears relatively common in adults, particularly those with HIV infection, bloodstream M. tuberculosis appears to be rare in children.

Azithromycin to prevent post-discharge morbidity and mortality in Kenyan children: a protocol for a randomised, double-blind, placebo-controlled trial (the Toto Bora trial)

INTRODUCTION

Child mortality due to infectious diseases remains unacceptably high in much of sub-Saharan Africa. Children who are hospitalised represent an accessible population at particularly high risk of death, both during and following hospitalisation. Hospital discharge may be a critical time point at which targeted use of antibiotics could reduce morbidity and mortality in high-risk children.

METHODS AND ANALYSIS

In this randomised, double-blind, placebo-controlled trial (Toto Bora Trial), 1400 children aged 1-59 months discharged from hospitals in Western Kenya, in Kisii and Homa Bay, will be randomised to either a 5-day course of azithromycin or placebo to determine whether a short course of azithromycin reduces rates of rehospitalisation and/or death in the subsequent 6-month period. The primary analysis will be modified intention-to-treat and will compare the rates of rehospitalisation or death in children treated with azithromycin or placebo using Cox proportional hazard regression. The trial will also evaluate the effect of a short course of azithromycin on enteric and nasopharyngeal infections and cause-specific morbidities. We will also identify risk factors for postdischarge morbidity and mortality and subpopulations most likely to benefit from postdischarge antibiotic use. Antibiotic resistance in Escherichia coli and Streptococcus pneumoniae among enrolled children and their primary caregivers will also be assessed, and cost-effectiveness analyses will be performed to inform policy decisions.

ETHICS AND DISSEMINATION

Study procedures were reviewed and approved by the institutional review boards of the Kenya Medical Research Institute, the University of Washington and the Kenyan Pharmacy and Poisons Board. The study is being externally monitored, and a data safety and monitoring committee has been assembled to monitor patient safety and to evaluate the efficacy of the intervention. The results of this trial will be published in peer-reviewed scientific journals and presented at relevant academic conferences and to key stakeholders.

TRIAL REGISTRATION NUMBER

NCT02414399.

Identification and management of Shigella infection in children with diarrhoea: a systematic review and meta-analysis

BACKGROUND

Shigella infections are a leading cause of diarrhoeal death among children in low-income and middle-income countries. WHO guidelines reserve antibiotics for treating children with dysentery. Reliance on dysentery for identification and management of Shigella infection might miss an opportunity to reduce Shigella-associated morbidity and mortality. We aimed to systematically review and evaluate Shigella-associated and dysentery-associated mortality, the diagnostic value of dysentery for the identification of Shigella infection, and the efficacy of antibiotics for children with Shigella or dysentery, or both.

METHODS

We did three systematic reviews (for mortality, diagnostic value, and antibiotic treatment of Shigella and dysentery), and meta-analyses where appropriate, of studies in resource-limited settings. We searched MEDLINE, Embase, and LILACS database for studies published before Jan 1, 2017, in English, French, and Spanish. We included studies of human beings with diarrhoea and accepted all study-specific definitions of dysentery. For the mortality and diagnostic value searches, we excluded studies that did not include an effect estimate or data necessary to calculate this estimate. The search for treatment included only randomised controlled trials that were done after Jan 1, 1980, and assessed antibiotics in children (aged <18 years) with dysentery or laboratory-confirmed Shigella. We extracted or calculated odds ratios (ORs) and 95% CIs for relative mortality and did random-effects meta-analysis to arrive at pooled ORs. We calculated 95% CIs assuming a binomial distribution and did random-effects meta-regression of log-transformed sensitivity and specificity estimates for diagnostic value. We assessed the heterogeneity of papers included in these meta-analyses using the I2 statistic and evaluated publication bias using funnel plots. This review is registered with PROSPERO (CRD42017063896).

FINDINGS

3649 papers were identified and 60 studies were included for analyses: 13 for mortality, 27 for diagnostic value, and 20 for treatment. Shigella infection was associated with mortality (pooled OR 2·8, 95% CI 1·6-4·8; p=0·000) whereas dysentery was not associated with mortality (1·3, 0·7-2·3; p=0·37). Between 1977 and 2016, dysentery identified 1·9-85·9% of confirmed Shigella infections, with sensitivity decreasing over time (p=0·04). Ten (50%) of 20 included antibiotic trials were among children with dysentery, none were placebo-controlled, and two (10%) evaluated antibiotics no longer recommended for acute infectious diarrhoea. Ciprofloxacin showed superior microbiological, but not clinical, effectiveness compared with pivmecillinam, and no superior microbiological and clinical effectiveness compared with gatifloxacin. Substantial heterogeneity was reported for meta-analyses of the Shigella-associated mortality studies (I2=78·3%) and dysentery-associated mortality studies (I2=73·2%). Too few mortality studies were identified to meaningfully test for publication bias. No evidence of publication bias was found in this analysis of studies of diagnostic value.

INTERPRETATION

Current WHO guidelines appear to manage dysentery effectively, but might miss opportunities to reduce mortality among children infected with Shigella who present without bloody stool. Further studies should quantify potential decreases in mortality and morbidity associated with antibiotic therapy for children with non-dysenteric Shigella infection.

FUNDING

Bill & Melinda Gates Foundation and the Center for AIDS Research International Core.

Impact of Childhood Nutritional Status on Pathogen Prevalence and Severity of Acute Diarrhea

Children with acute and chronic malnutrition are at increased risk of morbidity and mortality following a diarrheal episode. To compare diarrheal disease severity and pathogen prevalence among children with and without acute and chronic malnutrition, we conducted a cross-sectional study of human immunodeficiency virus-uninfected Kenyan children aged 6–59 months, who presented with acute diarrhea. Children underwent clinical and anthropometric assessments and provided stool for bacterial and protozoal pathogen detection. Clinical and microbiological features were compared using log binomial regression among children with and without wasting (mid-upper arm circumference ≤ 125 mm) or stunting (height-for-age z score ≤ −2). Among 1,363 children, 7.0% were wasted and 16.9% were stunted. After adjustment for potential confounders, children with wasting were more likely than nonwasted children to present with at least one Integrated Management of Childhood Illness danger sign (adjusted prevalence ratio [aPR]: 1.3, 95% confidence interval [CI]: 1.0 to 1.5, P = 0.05), severe dehydration (aPR: 2.4, 95% CI: 1.5 to 3.8, P < 0.01), and enteroaggregative Escherichia coli recovered from their stool (aPR: 1.8, 1.1–2.8, P = 0.02). There were no differences in the prevalence of other pathogens by wasting status after confounder adjustment. Stunting was not associated with clinical severity or the presence of specific pathogens. Wasted children with diarrhea presented with more severe disease than children without malnutrition which may be explained by a delay in care-seeking or diminished immune response to infection. Combating social determinants and host risk factors associated with severe disease, rather than specific pathogens, may reduce the disparities in poor diarrhea-associated outcomes experienced by malnourished children.

Defining Pediatric Diarrhea in Low-Resource Settings

Differences in definitions of acute pediatric diarrhea result in variable estimates of morbidity and mortality, treatment coverage, and associations with risk factors and outcomes. We reviewed published literature and guidelines focused on acute pediatric diarrhea in low- and middle-income countries. Clinical guidelines most commonly defined diarrhea in terms of quantity of loose or watery stool with consideration of normal stool patterns, whereas research studies often relied exclusively on a quantitative definition. The most commonly used quantitative definition, ≥3 loose or watery stools in a 24-hour period, has been compared to gold standards of caregiver perception and visual inspection of stool, with variable agreement. Age, breast-feeding status, and setting (facility vs household-based) influence the performance of quantitative diarrhea definitions in children. Universal adoption of a set of valid gold standard definitions specifically aligned with various programmatic and research goals will lead to more accurate coverage estimates and better-informed resource prioritization.

Antimicrobial resistance of Klebsiella pneumoniae stool isolates circulating in Kenya

We sought to determine the genetic and phenotypic antimicrobial resistance (AMR) profiles of commensal Klebsiella spp. circulating in Kenya by testing human stool isolates of 87 K. pneumoniae and three K. oxytoca collected at eight locations. Over one-third of the isolates were resistant to ≥3 categories of antimicrobials and were considered multidrug-resistant (MDR). We then compared the resistance phenotype to the presence/absence of 238 AMR genes determined by a broad-spectrum microarray and PCR. Forty-six genes/gene families were identified conferring resistance to β-lactams (ampC/blaDHA, blaCMY/LAT, blaLEN-1, blaOKP-A/OKP-B1, blaOXA-1-like family, blaOXY-1, blaSHV, blaTEM, blaCTX-M-1 and blaCTX-M-2 families), aminoglycosides (aac(3)-III, aac(6)-Ib, aad(A1/A2), aad(A4), aph(AI), aph3/str(A), aph6/str(B), and rmtB), macrolides (mac(A), mac(B), mph(A)/mph(K)), tetracyclines (tet(A), tet(B), tet(D), tet(G)), ansamycins (arr), phenicols (catA1/cat4, floR, cmlA, cmr), fluoroquinolones (qnrS), quaternary amines (qacEΔ1), streptothricin (sat2), sulfonamides (sul1, sul2, sul3), and diaminopyrimidines (dfrA1, dfrA5, dfrA7, dfrA8, dfrA12, dfrA13/21/22/23 family, dfrA14, dfrA15, dfrA16, dfrA17). This is the first profile of genes conferring resistance to multiple categories of antimicrobial agents in western and central Kenya. The large number and wide variety of resistance genes detected suggest the presence of significant selective pressure. The presence of five or more resistance determinants in almost two-thirds of the isolates points to the need for more effective, targeted public health policies and infection control/prevention measures.

Low Bacteremia Prevalence Among Febrile Children in Areas of Differing Malaria Transmission in Rural Kenya: A Cross-Sectional Study

BACKGROUND

With malaria declining, other causes of fever may account for a substantial portion of severe childhood illness in sub-Saharan Africa. We determined prevalence, etiologies, and correlates of bacteremia among children in Western Kenya.

METHODS

In a cross-sectional study, febrile children aged 6 months to 15 years presenting to Kisii (low malaria endemicity) and Homabay (high malaria endemicity) Hospitals were enrolled and screened for malaria, human immunodeficiency virus (HIV) infection and bacteremia. Correlates of bacteremia were evaluated using logistic regression.

RESULTS

Among 1476 children enrolled, 48 (3.3%) had bacteremia (23 of 734, 3.1% in Kisii and 25 of 734, 3.4% in Homabay). Salmonella spp (19 typhi and 21 nontyphoidal salmonella) accounted for 83% (40 of 48) of isolates. The distribution of Salmonella spp was similar between sites. Bacteremia was associated with incomplete vaccination (adjusted odds ratio [aOR] = 2.1; 95% confidence interval [CI], 1.1-4.1), before treatment with antimalarials (aOR = 2.7; 95% CI, 1.4-4.1), having sought care elsewhere (aOR = 2.2; 95% CI, 1.2-4.0) and lower education of caregiver (aOR = 2.5; 95% CI, 1.1-4.8). Nontyphoidal salmonella bacteremia was associated with HIV (aOR = 6.8; 95% CI, 1.1-35.1) and anemia (hemoglobin <8 g/dL) (aOR = 5.2; 95% CI, 1.4-18.9).

CONCLUSIONS

Bacteremia was relatively uncommon, but children with HIV, anemia, incomplete vaccination, and/or persistent fever despite malaria treatment may have higher risk and may benefit from targeted bacterial culture and/or empiric antibiotic therapy.

Mycobacterium tuberculosis Bacteremia Among Acutely Febrile Children in Western Kenya

In children, Mycobacterium tuberculosis (M. tuberculosis) frequently disseminates systemically, presenting with nonspecific signs including fever. We determined prevalence of M. tuberculosis bacteremia among febrile children presenting to hospitals in Nyanza, Kenya (a region with high human immunodeficiency virus (HIV) and M. tuberculosis prevalence). Between March 2013 and February 2014, we enrolled children aged 6 months to 5 years presenting with fever (axillary temperature ≥ 37.5°C) and no recent antibiotic use. Blood samples were collected for bacterial and mycobacterial culture using standard methods. Among 148 children enrolled, median age was 3.1 years (interquartile range: 1.8-4.1 years); 10.3% of children were living with a household member diagnosed with M. tuberculosis in the last year. Seventeen percent of children were stunted (height-for-age z-score < -2), 18.6% wasted (weight-for-height z-score < -2), 2.7% were HIV-infected, and 14.2% were HIV-exposed uninfected. Seventeen children (11.5%) had one or more signs of tuberculosis (TB). All children had a Bacille Calmette-Guerin vaccination scar. Among 134 viable blood cultures, none (95% confidence interval: 0-2.7%) had Mycobacterium isolated. Despite exposure to household TB contacts, HIV exposure, and malnutrition, M. tuberculosis bacteremia was not detected in this pediatric febrile cohort, a finding consistent with other pediatric studies.

Frequency and correlates of malaria over-treatment in areas of differing malaria transmission: a cross-sectional study in rural Western Kenya

Background

In 2010, the World Health Organization shifted its malaria guidelines from recommending the empiric treatment of all febrile children to treating only those with laboratory-confirmed malaria. This study evaluated the frequency and predictors of malaria over-treatment among febrile malaria-negative children in Kenya.

Methods

Between 2012 and 2013, 1,362 children presenting consecutively with temperature ≥37.5°C to Kisii and Homa Bay hospitals were enrolled in a cross-sectional study evaluating causes of fever. Children were screened for malaria using smear microscopy and rapid diagnostic tests and managed according to standard of care at the hospitals. The frequency of anti-malarial prescriptions among children with laboratory-confirmed malaria negative children (malaria over-treatment) was determined; and clinical and demographic correlates of overtreatment evaluated using logistic regression. Because of differences in malaria endemicity, analyses were stratified and compared by site.

Results

Among 1,362 children enrolled, 46 (7%) of 685 children in Kisii, and 310 (45.8%) of 677 in Homa Bay had laboratory-confirmed malaria; p < 0.001. Among malaria-negative children; 210 (57.2%) in Homa Bay and 45 (7.0%) in Kisii received anti-malarials; p < 0.001. Predictors of over-treatment in Homa Bay included ≥ one integrated management of childhood illness (IMCI) danger sign (aOR = 8.47; 95% CI: 4.81-14.89), fever lasting ≥ seven days (aOR = 4.94; 95% CI: 1.90-12.86), and fever ≥39°C (aOR = 3.07; 95% CI: 1.58-5.96). In Kisii, only fever ≥39°C predicted over-treatment (aOR = 2.13; 95% CI: 1.02-4.45).

Conclusions

Malaria over-treatment was common, particularly in Homa Bay, where the prevalence of malaria was extremely high. Severe illness and high or prolonged fever were associated with overtreatment. Overtreatment may result in failure to treat other serious causes of fever, drug resistance, and unnecessarily treatment costs.

Management of diarrhea in HIV-affected infants and children

Globally, diarrhea is the second leading cause of death in children less than 5 years of age. HIV-infected and HIV-exposed uninfected (HEU) children are at high risk of dying from diarrhea and may be more susceptible to the highest risk enteric pathogens. This increased risk associated with HIV infection and HIV exposure is likely multifactorial. Factors such as immunosuppression, proximity to individuals more likely to be shedding pathogens, and exposure to antimicrobial prophylaxis may alter the risk profile in these children. Current international guidelines do not differentiate management strategies on the basis of whether children are infected or affected by HIV, despite likely differences in etiologies and consequences. Reducing diarrhea mortality in high HIV prevalence settings will require strengthening of HIV testing and treatment programs; improvements in water, sanitation and hygiene interventions targeted at HIV-affected households; and reconsideration of the use of empiric antimicrobial treatment of pathogens known to infect HIV-infected and HEU children disproportionately.

Water filter provision and home-based filter reinforcement reduce diarrhea in Kenyan HIV-infected adults and their household members

Among human immunodeficiency virus (HIV)-infected adults and children in Africa, diarrheal disease remains a major cause of morbidity and mortality. We evaluated the effectiveness of provision and home-based reinforcement of a point-of-use water filtration device to reduce diarrhea among 361 HIV-infected adults in western Kenya by comparing prevalence of self-reported diarrhea before and after these interventions. After provision of the filter, 8.7% of participants reported diarrhea compared with 17.2% in the 3 months before filter provision (odds ratio [OR] = 0.39, 95% confidence interval [95% CI] = 0.23-0.66, P < 0.001). The association was similar among 231 participants who were already taking daily cotrimoxazole prophylaxis before being given a filter (OR = 0.47, 95% CI = 0.25-0.88, P = 0.019). Educational reinforcement was also associated with a modest reduction in self-reported diarrhea (OR = 0.50, 95% CI = 0.20-0.99, P = 0.047). Provision and reinforcement of water filters may confer significant benefit in reducing diarrhea among HIV-infected persons, even when cotrimoxazole prophylaxis is already being used.