Treatment of infectious diarrhea in children

Derivation and validation of a clinical predictive model for longer duration diarrhea among pediatric patients in Kenya using machine learning algorithms

BACKGROUND

Despite the adverse health outcomes associated with longer duration diarrhea (LDD), there are currently no clinical decision tools for timely identification and better management of children with increased risk. This study utilizes machine learning (ML) to derive and validate a predictive model for LDD among children presenting with diarrhea to health facilities.

METHODS

LDD was defined as a diarrhea episode lasting ≥ 7 days. We used 7 ML algorithms to build prognostic models for the prediction of LDD among children < 5 years using de-identified data from Vaccine Impact on Diarrhea in Africa study (N = 1,482) in model development and data from Enterics for Global Health Shigella study (N = 682) in temporal validation of the champion model. Features included demographic, medical history and clinical examination data collected at enrolment in both studies. We conducted split-sampling and employed K-fold cross-validation with over-sampling technique in the model development. Moreover, critical predictors of LDD and their impact on prediction were obtained using an explainable model agnostic approach. The champion model was determined based on the area under the curve (AUC) metric. Model calibrations were assessed using Brier, Spiegelhalter's z-test and its accompanying p-value.

RESULTS

There was a significant difference in prevalence of LDD between the development and temporal validation cohorts (478 [32.3%] vs 69 [10.1%]; p < 0.001). The following variables were associated with LDD in decreasing order: pre-enrolment diarrhea days (55.1%), modified Vesikari score(18.2%), age group (10.7%), vomit days (8.8%), respiratory rate (6.5%), vomiting (6.4%), vomit frequency (6.2%), rotavirus vaccination (6.1%), skin pinch (2.4%) and stool frequency (2.4%). While all models showed good prediction capability, the random forest model achieved the best performance (AUC [95% Confidence Interval]: 83.0 [78.6-87.5] and 71.0 [62.5-79.4]) on the development and temporal validation datasets, respectively. While the random forest model showed slight deviations from perfect calibration, these deviations were not statistically significant (Brier score = 0.17, Spiegelhalter p-value = 0.219).

CONCLUSIONS

Our study suggests ML derived algorithms could be used to rapidly identify children at increased risk of LDD. Integrating ML derived models into clinical decision-making may allow clinicians to target these children with closer observation and enhanced management.

SLC26A3 (DRA, the Congenital Chloride Diarrhea Gene): A Novel Therapeutic Target for Diarrheal Diseases

Diarrhea associated with enteric infections, gut inflammation, and genetic defects poses a major health burden and results in significant morbidity and mortality. Impaired fluid and electrolyte absorption or secretion in the intestine are the hallmark of diarrhea. Electroneutral NaCl absorption in the mammalian GI tract involves the coupling of Na+/H+ and Cl-/HCO3- exchangers. SLC26A3 (Down Regulated in Adenoma, DRA) is the major anion exchanger involved in luminal Cl- absorption and HCO3- secretion. Mutations in the SLC26A3 gene cause a severe disease called congenital chloride diarrhea (CLD). Multiple studies have shown that DRA function or expression is downregulated in infectious diarrheal disorders caused by EPEC, C rodentium, Salmonella, Clostridioides difficile and Cryptosporidium parvum infection. In addition, DRA levels are severely depleted in colonic mucosa of IBD patients and in mouse models of IBD (eg, DSS, TNBS, adoptive T-cell transfer, anti-CD-40, and IL-10 KO colitis). In addition, genetic defects exhibiting diarrhea including microvillus inclusion disease (MVID), keratin-8 depletion, knock-out mouse models of transcriptional factors (eg, CDX-2 and HNF1α/1β) also exhibit severe down regulation of DRA. Also, recent studies have shown that DRA is not only critical for chloride absorption but also plays a key role in maintaining gut epithelial barrier integrity, microbiome composition, and has now emerged as an IBD susceptibility gene. In this review, we provide strong evidence that DRA may serve as a novel therapeutic target with dual benefits in not only correcting diarrheal phenotype but also improving gut barrier integrity and inflammation in pathogen infection or IBD.

Characteristics and outcomes of children 2-23 months of age with prolonged diarrhoea: A secondary analysis of data from the 'Antibiotics for Children with Diarrhea' trial

Background

Approximately 12% of all diarrhoeal episodes last for 7-13 days. As such, they are termed prolonged diarrhoea, and are associated with over two-thirds of all diarrhoeal deaths. Due to a lack of robust data, we aimed to evaluate a comparative background characteristics of young children with acute and prolonged diarrhoea, and their outcomes at day 90 follow-up.

Methods

We performed a secondary analysis of data from the Antibiotics for Children with Diarrhea (ABCD) trial. Children aged 2-23 months were enrolled between July 2017 and July 2019 from seven Asian and sub-Saharan African countries. For this analysis, we divide diarrhoea into two categories: acute diarrhoea (duration <7 days) and prolonged diarrhoea (duration ≥7-13 days). We used logistic regression to observe baseline crude and adjusted associations and linear regression to compare post-discharge outcomes.

Results

We analysed data on 8266 children, of whom 756 (9%) had prolonged diarrhoea and 7510 (91%) had acute diarrhoea. Pakistan had the highest proportion of children with prolonged diarrhoea (n/N = 178/1132, 16%), while Tanzania had the lowest (n/N = 12/1200, 1%). From an analysis that adjusted for sex, breastfeeding, nutritional status, clinical presentation, housing, water supply, sanitation, and country, we observed that presentation at a health facility with prolonged diarrhoea was associated with low age (2-12 months) (adjusted odds ratio (aOR) = 1.25; 95% confidence interval (CI) = 1.02, 1.53; P = 0.028), presence of three or more under-five children in the family (aOR = 1.54; 95% CI = 1.26, 1.87; P < 0.001), maternal illiteracy (aOR = 1.45; 95% CI = 1.21, 1.74, P < 0.001), moderate underweight (aOR = 1.25; 95% CI = 1.01, 1.55; P = 0.042) and pathogen (Campylobacter) (aOR = 1.27; 95% CI = 1.12, 1.44; P < 0.001). At day 90 follow-up, children with prolonged diarrhoea had significantly lower weight-for-age z-score compared to children with acute diarrhoea (-1.62, standard deviation (SD) = 1.11 vs -1.52, SD = 1.20; P = 0.032), as well as significantly higher frequency of hospital admission (6.1% vs 4.5%; P = 0.042).

Conclusions

Prolonged diarrhoea was more common in children of younger age, those who were moderately underweight, those with Campylobacter in stool, those with three or more under-five children in a family, and those with illiterate mothers compared to those who had acute diarrhoea. Children with prolonged diarrhoea more often required hospitalisation during the three-month follow-up period compared to their counterparts.

Ethnobotany, phytochemistry, and biological activities of Psidium guajava in the treatment of diarrhea: a review

Psidium guajava: is a tropical tree that is widely used in traditional medicine, especially for treating diarrhea. While P. guajava has been the subject of numerous reviews, none have specifically examined its ethnobotany, pharmacology, and phytochemistry in relation to its antidiarrheal activity. This review aims to summarize the evidence of effectiveness and safety of P. guajava in the treatment of diarrhea. Literature searches were conducted through Web of Science, PubMed, and ScienceDirect by using keywords "Psidium guajava" and "diarrhea" in October 2022. A total of 189 studies were included in this review. P. guajava is widely used in traditional medicine in 44 countries. Decoction and oral were the most represented method of preparation and administration, respectively, while leaves represented the most frequently cited part of the plant. Around 27 antidiarrheal or antibacterial compounds have been isolated and identified, including benzophenone glycosides, terpenes, polysaccharides, phenols, and flavonoids. This article presents ethnobotanical and pharmacological evidence for the efficacy of P. guajava leaves in the treatment of diarrhea and provides reference information for further investigation of this plant. However, despite the large number of publications on the topic, there are still some questions to answer: are quercetin and its glycosides the only ones to act as antidiarrheal agents? What is the mechanism of action of P. guajava antidiarrheal compounds? are the use of guava leaves safe in all types of populations including children, and at what dosage? To answer these questions, more complete phytochemical studies and systematic clinical trials are needed.

Investigation of the vaccine potential of an in silico designed FepA peptide vaccine against Shigella flexneri in mice model

Background

Shigellosis is one of the significant causes of diarrhea in Bangladesh. It is a global health problem; approximately 1.3 million people die yearly from Shigellosis. The current treatment method, using different antibiotics against Shigellosis is ineffective. Moreover, it becomes a worrying situation due to the emergence of antibiotic-resistant pathogenic microbes responsible for these diarrheal diseases.

Methodology

Previous immunoinformatics study predicted a potential peptide from the Ferric enterobactin protein (FepA) of Shigella spp. In this study, we have chemically synthesized the FepA peptide. As a highly immunogenic, FepA peptide conjugated with KLH has been tested in mice model with complete and incomplete adjuvants as a vaccine candidate.

Results

Immunological analysis showed that all vaccinated mice were immunologically boosted, which was statistically significant (P-value 0.0325) compared to control mice. Immunological analysis for bacterial neutralization test result was also statistically significant (P-value 0.0468), where each ELISA plate was coated with 1 × 107S. flexneri cells. The Challenge test with 1 × 1012S. flexneri cells to each vaccinated and controlled mice showed that 37.5 % of control (non-vaccinated) mice died within seven days after the challenge was given while 100 % of vaccinated mice remained strong and stout. The analyses of the post-challenge weight loss of the mice were also significant (P-value 0.0367) as the weight loss percentage in control mice was much higher than in the vaccinated mice. The pathological and phenotypic appearances of vaccinated mice were also clearly differentiable compared with control mice. Thus all these immunological analysis and pathological appearances directly supported our FepA peptide as a potential immune booster.

Conclusion

This study provides evidence that the FepA peptide is a highly immunogenic vaccine candidate against S. flexneri. Therefore, these findings inspire future trials for the evaluation of the suitability of this vaccine candidate against Shigellosis.

Combatting infectious diarrhea: innovations in treatment and vaccination strategies

INTRODUCTION

The escalating prevalence of infectious diseases is an important cause of concern in society. Particularly in several developing countries, infectious diarrhea poses a major problem, with a high fatality rate, especially among young children. The condition is divided into four classes, namely, acute diarrhea, invasive diarrhea, acute bloody diarrhea, and chronic diarrhea. Various pathogenic agents, such as bacteria, viruses, protozoans, and helminths, contribute to the onset of this condition.

AREAS COVERED

The review discusses the scenario of infectious diarrhea, the prevalent types, as well as approaches to management including preventive, therapeutic, and vaccination strategies. The vaccination techniques are extensively discussed including the available vaccines, their advantages as well as limitations.

EXPERT OPINION

There are several approaches available to develop new-improved vaccines. In addition, route of immunization is important and aerosols/nasal sprays, oral route, skin patches, powders, and liquid jets to minimize needles can be used. Plant-based vaccines, such as rice, might save packing and refrigeration costs by being long-lasting, non-refrigerable, and immunogenic. Future research should utilize predetermined PCR testing intervals and symptom monitoring to identify persistent pathogens after therapy and symptom remission.

Burden, predictors, and outcome of unconsciousness among under-five children hospitalized for community-acquired pneumonia: A retrospective study from a developing country

Despite the reduction of death from pneumonia over recent years, pneumonia has still been the leading infectious cause of death in under-five children for the last several decades. Unconsciousness is a critical condition in any child resulting from any illness. Once it occurs during a pneumonia episode, the outcome is perceived to be fatal. However, data on children under five with pneumonia having unconsciousness are scarce. We've retrospectively analyzed the data of under-five children admitted at the in-patient ward of Dhaka Hospital of icddr,b during 1 January 2014 and 31 December 2017 with World Health Organization classified pneumonia or severe pneumonia. Children presented with or without unconsciousness were considered as cases and controls respectively. Among a total of 3,876 children fulfilling the inclusion criteria, 325 and 3,551 were the cases and the controls respectively. A multivariable logistic regression analysis revealed older children (8 months vs. 7.9 months) (adjusted odds ratio, aOR 1.02, 95% CI: 1.004-1.04, p = 0.015), hypoxemia (aOR 3.22, 95% CI: 2.39-4.34, p<0.001), severe sepsis (aOR 4.46, 95% CI: 3.28-6.06, p<0.001), convulsion (aOR 8.90, 95% CI: 6.72-11.79, p<0.001), and dehydration (aOR 2.08, 95% CI: 1.56-2.76, p<0.001) were found to be independently associated with the cases. The cases more often had a fatal outcome than the controls (23% vs. 3%, OR 9.56, 95% CI: 6.95-13.19, p<0.001). If the simple predicting factors of unconsciousness in children under five hospitalized for pneumonia with different severity can be initially identified and adequately treated with prompt response, pneumonia-related deaths can be reduced more effectively, especially in resource-limited settings.

Factors associated with dehydrating rotavirus diarrhea in children under five in Bangladesh: An urban-rural comparison

Introduction

Rotavirus is the leading cause of dehydrating diarrhea in young children worldwide. This study aimed to identify the factors associated with dehydrating rotavirus diarrhea in children under five years of age in urban and rural Bangladesh.

Methods

The study analyzed data from 7,758 children under five who presented with rotavirus diarrhea to Dhaka (urban) and Matlab (rural) hospital of icddr,b during 2009–2018, and were enrolled in the Diarrheal Disease Surveillance System. Cases were defined as children having rotavirus isolated in stool specimens presented with dehydrating diarrhea. Controls were children infected with rotavirus have no dehydration. Multivariable logistic regression models were built to identify the factors associated with dehydrating diarrhea.

Results

Among the rotavirus-infected children, 1,784 (34%) in Dhaka and 160 (6%) in Matlab had diarrhea with some or severe dehydration. The female children and age group 24–59 months age was found to be at higher risk of dehydration compared to 6–11 months age. In the multivariable logistic regression model, maternal illiteracy, vomiting, the onset of diarrhea less than 24 hours prior to presenting to the hospital, monsoon months, stunting, and wasting were significantly associated with dehydrating rotavirus diarrhea among children aged 0–59 months in Dhaka. In Matlab, monthly income, duration less than 24 hours prior to attending the hospital, and wasting had an independent significant association with dehydrating rotavirus diarrhea episodes.

Conclusions

Considering factors diversity, educating parents and proper counselling by health care personnel during diarrhea, could lessen the severity of dehydration and the number of hospital visits later on by eliminating the modifiable risk factors among the children, which needs further studies.

Evaluation and Management of Traveler's Diarrhea in Children

Traveler's diarrhea is the most common travel disease in both children and adults. Adult guidelines for traveler's diarrhea have been established, but significant gaps persist in guidance for the evaluation and management of pediatric traveler's diarrhea. Adult guidelines are not necessarily applicable in children, and it is essential for clinicians to account for the differences in pediatric pathophysiology, clinical presentations, and treatment recommendations when evaluating and managing pediatric traveler's diarrhea.

Characteristics of severely malnourished under-five children immunized with Bacillus Calmette-Guérin following Expanded Programme on Immunization schedule and their outcomes during hospitalization at an urban diarrheal treatment centre, Bangladesh

Background

Bacillus Calmette-Guérin (BCG) vaccination has recently been found to have beneficial effects among children infected other than Mycobacterium tuberculosis. Due to the paucity of data on the outcomes of children who had successful BCG vaccination following Expanded Programme on Immunization (EPI) schedule, we aimed to investigate the characteristics of such children and their outcomes who were hospitalized for severe malnutrition.

Methods

A prospective observational study was conducted to determine the viral etiology of pneumonia in severely malnourished children those were admitted to the Dhaka Hospital of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) between April 2015 and December 2017, constituted the study population. Using a case-control design for the analysis, children having BCG vaccination prior hospital admission were treated as cases (n = 611) and those without vaccination, constituted as controls (n = 83). Bi-variate analysis was conducted using socio-demographic, clinical, laboratory, and treatment characteristics on admission and outcomes during hospitalization. Finally, log-linear binomial regression analysis was done to identify independent impact of BCG vaccination.

Results

The cases more often presented with older age, have had lower proportion of maternal illiteracy, higher rate of breastfeeding, severe wasting and lower rate of hypoglycemia, compared to the controls. The cases were also found to have lower risk of severe sepsis and deaths, compared to the controls (for all, p<0.05). However, in log-linear binomial regression analysis, after adjusting for potential confounders, BCG vaccination following EPI schedule (RR:0.54; 95%CI = 0.33–0.89; p = 0.015) and breastfeeding (RR:0.53; 95%CI = 0.35–0.81; p = 0.003) were found to be protective for the development of severe sepsis.

Conclusion

BCG vaccination and breastfeeding were found to be protective for the development of severe sepsis in hospitalized severely malnourished under-five children which underscores the importance of continuation of BCG vaccination at birth and breastfeeding up to two years of age.

Inhibition of α-, β- and γ-carbonic anhydrases from the pathogenic bacterium Vibrio cholerae with aromatic sulphonamides and clinically licenced drugs - a joint docking/molecular dynamics study

The binding mode of aromatic sulphonamides and clinically licenced drugs to the three carbonic anhydrase (CA, EC 4.2.1.1) isoforms from the human pathogen V. cholerae was here thouroghly characterised by a joint docking and molecular dynamics in silico protocol. In fact, VchCA, VchCAβ, and VchCAγ are crucial in the pathogen life cycle and growth and represent innovative targets to fight V. cholerae proliferation overcoming the spreading chemoresistance to the available drugs. A set of 40 sulphonamides/sulfamates VchCAs inhibitors was studied using the proteins homology built 3 D models unveiling the key and stable interactions responsible for a potent CA inhibition. This study has the aim to offer insights and guidelines for the future rational design of potent and selective inhibitors targeting CA isoforms from V. cholerae or other human pathogens.

The Combined Beneficial Effects of Postbiotic Butyrate on Active Vitamin D3-Orchestrated Innate Immunity to Salmonella Colitis

Salmonella spp. Remains a major public health problem globally. Biomedicine is the cornerstone of modern health care and could be a solution for antibiotic-resistant Salmonellosis. Although postbiotics seem to be an effective treatment in various clinical conditions, their clinical effects on Salmonella colitis have not been reported. Our previous report revealed that active vitamin D attenuates the severity of Salmonella colitis and invasiveness by reducing inflammation and enhancing the production of antimicrobial peptides. Therefore, we investigated the synergistic effects of butyrate, the most studied postbiotic, and active vitamin D on the severity of Salmonella colitis, invasiveness of Salmonella, and host immune responses, as well as its novel mechanisms, using in vitro and in vivo studies. We demonstrated that a combination of butyrate and active vitamin D (1 alpha, 25-dihydroxyvitamin D3) synergically reduced the severity of Salmonella colitis in C57BL/6 mice and reduced cecal inflammatory mIL-6, mIL-8, mTNF-α, and mIL-1β mRNA expression, but enhanced the antimicrobial peptide mhBD-3 mRNA, compared to a single treatment. Additionally, upregulated vitamin D receptor (VDR) plays a critical role in the synergistic effects. This suggests combined benefits of butyrate and active vitamin D on Salmonella colitis through VDR-mediated antibacterial and anti-inflammatory responses. The combined use of both supplements could be a potential biomedicine for infectious and autoimmune colitis.

Early management of hypokalaemia in severely malnourished children under five could help to reduce deaths in developing countries

AIM

This study evaluated the factors associated with hypokalaemia and their outcomes, in severely malnourished children under 5 years of age.

METHODS

We focused on 407 severely malnourished children under five who were admitted to the Dhaka Hospital, International Centre for Diarrhoeal Disease Research, Bangladesh, from April 2011 to June 2012. The cases were 139 with hypokalaemia, and the comparisons were 268 without hypokalaemia.

RESULTS

Cases were older than the comparisons, with a poor socio-economic status and a higher death rate of 12% vs 7%. They were more likely to present with a history of measles, diarrhoea, lethargy, lower pulse rates, hyponatraemia, metabolic acidosis, hypocalcaemia, hypomagnesaemia, higher height or length, severe underweight, severe wasting and leucocytosis on admission. At discharge, cases had lower potassium levels and a higher proportion had persistent hypokalaemia. Cases received longer treatment with ampicillin and micronutrients. After adjusting for confounders, hypokalaemia was independently associated with poor socio-economic status, diarrhoea, lower pulse rates, hypocalcaemia, metabolic acidosis and leucocytosis.

CONCLUSION

Identifying simple clinical signs, like diarrhoea and lower pulse rates, and laboratory parameters, such as hypocalcaemia and metabolic acidosis, may enable the early management of hypokalaemia in severely malnourished children under 5 years. This could reduce morbidity and mortality.

The economic burden of diarrhea in children under 5 years in Bangladesh

BACKGROUND

Diarrhea is a leading cause of morbidity and mortality among under-five children in Bangladesh. Hospitalization for diarrhea can pose a significant burden on households and health systems. The aim of this study was to estimate the cost of illness due to diarrhea from the healthcare facility, caregiver, and societal perspectives in Bangladesh.

METHOD

A cross-sectional study with an ingredient-based costing approach was conducted in 48 healthcare facilities in Bangladesh. In total, 899 caregivers of under-five children with diarrhea were interviewed face-to-face between August 2017 and May 2018, followed up over phone after 7-14 days of discharge, to capture all expenses and time costs related to the entire episode of diarrhea.

RESULTS

The average cost per episode for caregivers was US$62, with $29 direct and $34 indirect costs. From the societal perspective, average cost per episode of diarrhea was $71. In 2018, an estimated $79 million of economic costs were incurred for treating diarrhea in Bangladesh. Using 10% of income as threshold, over 46% of interviewed households faced catastrophic expenditure from diarrheal disease.

CONCLUSION

The economic costs incurred by caregivers for treating per-episode of diarrhea was around 4% of the annual national gross domestic product per-capita. Investment in vaccination can help to reduce the prevalence of diarrheal diseases and avert this public health burden.

GUT MICROBIOTA, PREBIOTICS, PROBIOTICS, AND SYNBIOTICS IN GASTROINTESTINAL AND LIVER DISEASES: PROCEEDINGS OF A JOINT MEETING OF THE BRAZILIAN SOCIETY OF HEPATOLOGY (SBH), BRAZILIAN NUCLEUS FOR THE STUDY OF HELICOBACTER PYLORI AND MICROBIOTA (NBEHPM), AND BRAZILIAN FEDERATION OF GASTROENTEROLOGY (FBG)

Over the last years, there is growing evidence that microorganisms are involved in the maintenance of our health and are related to various diseases, both intestinal and extraintestinal. Changes in the gut microbiota appears to be a key element in the pathogenesis of hepatic and gastrointestinal disorders, including non-alcoholic fatty liver disease, alcoholic liver disease, liver cirrhosis, inflammatory bowel disease, irritable bowel syndrome, and Clostridium difficile - associated diarrhea. In 2019, the Brazilian Society of Hepatology (SBH) in cooperation with the Brazilian Nucleus for the Study of Helicobacter Pylori and Microbiota (NBEHPM), and Brazilian Federation of Gastroenterology (FBG) sponsored a joint meeting on gut microbiota and the use of prebiotics, probiotics, and synbiotics in gastrointestinal and liver diseases. This paper summarizes the proceedings of the aforementioned meeting. It is intended to provide practical information about this topic, addressing the latest discoveries and indicating areas for future studies.

Cholera and Pancreatic Cholera: Is VIP the Common Pathophysiologic Factor?

Background: Cholera remains a major global health problem, causing high output diarrhea leading to severe dehydration and shock in developing countries. We aimed to determine whether vasoactive intestinal polypeptide (VIP), the mediator of pancreatic cholera syndrome, has a role in the pathophysiology of human cholera. Methods: We conducted a prospective observational study of cholera cases hospitalized with severe dehydration. Plasma and stool water levels of VIP were measured just after admission, after complete rehydration (3–4 h), at 24 h post-rehydration and at discharge after diarrhea ceased. Results: In total, 23 cholera patients were examined between January and August 2018. The geometric mean of stool VIP (sVIP) and plasma VIP (pVIP) on admission were 207.67 and 8.34 pmol/L, respectively. pVIP values were all within the normal range (</= 30 pcmol/L); however, sVIP levels were very high at all timepoints, though less so just after rehydration. In multivariable GEE models, after adjustment for covariates, sVIP levels were significantly associated with duration of hospitalization (p = 0.026), total stool volume (p = 0.023) as well as stool output in the first 24 h (p = 0.013). Conclusions: The data suggest that VIP, which is released by intestinal nerves, may play an important role in human choleragenesis, and inhibitors of intestinal VIP merit testing for potential therapeutic benefits.

Randomised trial showed that rapid rehydration of severely malnourished children with dehydrating diarrhoea was as safe and effective as slow rehydration

AIM

This study evaluated the effectiveness and safety of rapid and slow rehydration in children aged 6-60 months with dehydrating diarrhoea and severe malnutrition.

METHODS

A randomised controlled trial was conducted from July 2011 to March 2014 at the International Centre for Diarrhoeal Disease Research Bangladesh. We included children with weight for age and, or, weight for length Z-scores of less than -3 or with bipedal oedema and acute diarrhoea with severe dehydration. The children received intravenous fluid at different rates: 105 rapidly over six hours and 103 slowly over the 12 hours recommended by the World Health Organization.

RESULTS

All the children were successfully rehydrated. The admittance weights were similar for the slow and rapid groups: 8.4 kg and 8.3 kg. After 24 hours, the mean percentage weight gain was 8.5% and 9.0%, respectively. This confirmed that most of the children had been suffering from severe dehydration on admission. The respective proportions of children who received unscheduled intravenous fluid were 18% and 17%. None developed fluid overload or heart failure and most recovered normal renal function after rehydration.

CONCLUSION

Rapid rehydration saved time, was as safe as slow rehydration and was a better option for dehydrating diarrhoea and severe malnutrition.

Protracted cholera outbreak in the Central Region, Ghana, 2016

OBJECTIVE

On 24th October 2016, the Central Regional Health Directorate received report of a suspected cholera outbreak in the Cape Coast Metropolis (CCM). We investigated to confirm the diagnosis, identify risk factors and implement control measures.

DESIGN

We used a descriptive study followed by 1:2 unmatched case-control study.

DATA SOURCE

We reviewed medical records, conducted active case search and contact tracing, interviewed case-patients and their contacts and conducted environmental assessment. Case-patients' stool samples were tested with point of care test kits (SD Bioline Cholera Ag 01/0139) and sent to the Cape Coast Teaching Hospital Laboratory for confirmation.

MAIN OUTCOMES

Cause of outbreak, risk factors associated with spread of outbreak.

RESULTS

Vibrio cholerae serotype Ogawa caused the outbreak. There was no mortality. Of 704 case-patients, 371(52.7%) were males and 55(7.8%) were aged under-five years. The median age was 23 years (interquartile range: 16-32 years). About a third 248(35.2%) of the case patients were aged 15-24 years. The University of Cape Coast subdistrict was the epicenter with 341(48.44%) cases. Compared to controls, cholera case-patients were more likely to have visited Cholera Treatment Centers (CTC) (aOR=12.1, 95%CI: 1.5-101.3), drank pipe-borne water (aOR=11.7, 95%CI: 3.3-41.8), or drank street-vended sachet water (aOR=11.0, 95%CI: 3.7-32.9). Open defecation and broken sewage pipes were observed in the epicenter.

CONCLUSION

Vibrio cholerae serotype Ogawa caused the CCM cholera outbreak mostly affecting the youth. Visiting CTC was a major risk factor. Prompt case-management, contact tracing, health education, restricting access to CTC and implementing water sanitation and hygiene activities helped in the control.

FUNDING

This work was supported by Ghana Field Epidemiology and Laboratory Training Program (GFELTP), University of Ghana.

Comparative Genomics Reveals the Genetic Mechanisms of Musk Secretion and Adaptive Immunity in Chinese Forest Musk Deer

The Chinese forest musk deer (Moschus berezovskii; FMD) is an artiodactyl mammal and is both economically valuable and highly endangered. To investigate the genetic mechanisms of musk secretion and adaptive immunity in FMD, we compared its genome to nine other artiodactyl genomes. Comparative genomics demonstrated that eight positively selected genes (PSGs) in FMD were annotated in three KEGG pathways that were related to metabolic and synthetic activity of musk, similar to previous transcriptome studies. Functional enrichment analysis indicated that many PSGs were involved in the regulation of immune system processes, implying important reorganization of the immune system in FMD. FMD-specific missense mutations were found in two PSGs (MHC class II antigen DRA and ADA) that were classified as deleterious by PolyPhen-2, possibly contributing to immune adaptation to infectious diseases. Functional assessment showed that the FMD-specific mutation enhanced the ADA activity, which was likely to strengthen the immune defense against pathogenic invasion. Single nucleotide polymorphism-based inference showed the recent demographic trajectory for FMD. Our data and findings provide valuable genomic resources not only for studying the genetic mechanisms of musk secretion and adaptive immunity, but also for facilitating more effective management of the captive breeding programs for this endangered species.

Chronic antibiotic use during adulthood and weight change in the Sister Study

BACKGROUND/OBJECTIVES

Antibiotic use in early life has been associated with weight gain in several populations. However, associations between chronic antibiotic use and weight among adults in the general population are unknown.

SUBJECTS/METHODS

The NIEHS Sister Study is a longitudinal cohort of sisters of women with breast cancer. We examined associations between chronic antibiotic use (≥ 3 months) during the fourth decade of life (30-39 years) and subsequent obesity at enrollment (mean age = 55) via logistic regression. We also examined associations between chronic antibiotic use in the 5 years and 12 months prior to enrollment and weight gain after enrollment in linear mixed models. Models were adjusted for race/ethnicity, education, urban/rural status, age, and smoking.

RESULTS

In adjusted analyses (n = 50,237), chronic penicillin use during the 4th decade of life was associated with obesity at enrollment (OR 2.00, 95% CI 1.40, 2.87), and use in the 5 years prior to enrollment was associated with increased BMI change after enrollment (β 1.00 95% CI 0.01, 2.00). Use of bactericidals (OR 1.71, 95% CI 1.29, 2.26) during the 4th decade of life was also associated with obesity at enrollment. Associations for penicillins and bactericidals were consistent across indications for use. Bacteriostatic use in the 5 years prior to enrollment was associated with a reduction in BMI after enrollment (β -0.52, 95% CI -1.04, 0.00), and tetracycline use during the 4th decade of life was associated with reduced odds of obesity at enrollment (OR 0.72, 95% CI 0.56, 0.92). However, these inverse associations were only present for those who reported taking antibiotics for skin purposes. Cephalosporins, macrolides, quinolones, and sulfonamides were not associated with BMI change over time.

CONCLUSIONS

Chronic use of antibiotics during adulthood may have long-lasting impacts on BMI. Associations may differ by antibiotic class, and confounding by indication may be important for some antibiotic classes.

Vibrio spp. infections

Vibrio is a genus of ubiquitous bacteria found in a wide variety of aquatic and marine habitats; of the >100 described Vibrio spp., ~12 cause infections in humans. Vibrio cholerae can cause cholera, a severe diarrhoeal disease that can be quickly fatal if untreated and is typically transmitted via contaminated water and person-to-person contact. Non-cholera Vibrio spp. (for example, Vibrio parahaemolyticus, Vibrio alginolyticus and Vibrio vulnificus) cause vibriosis - infections normally acquired through exposure to sea water or through consumption of raw or undercooked contaminated seafood. Non-cholera bacteria can lead to several clinical manifestations, most commonly mild, self-limiting gastroenteritis, with the exception of V. vulnificus, an opportunistic pathogen with a high mortality that causes wound infections that can rapidly lead to septicaemia. Treatment for Vibrio spp. infection largely depends on the causative pathogen: for example, rehydration therapy for V. cholerae infection and debridement of infected tissues for V. vulnificus-associated wound infections, with antibiotic therapy for severe cholera and systemic infections. Although cholera is preventable and effective oral cholera vaccines are available, outbreaks can be triggered by natural or man-made events that contaminate drinking water or compromise access to safe water and sanitation. The incidence of vibriosis is rising, perhaps owing in part to the spread of Vibrio spp. favoured by climate change and rising sea water temperature.

The Role of Ion Transporters in the Pathophysiology of Infectious Diarrhea

Every year, enteric infections and associated diarrhea kill millions of people. The situation is compounded by increases in the number of enteric pathogens that are acquiring resistance to antibiotics, as well as (hitherto) a relative paucity of information on host molecular targets that may contribute to diarrhea. Many forms of diarrheal disease depend on the dysregulation of intestinal ion transporters, and an associated imbalance between secretory and absorptive functions of the intestinal epithelium. A number of major transporters have been implicated in the pathogenesis of diarrheal diseases and thus an understanding of their expression, localization, and regulation after infection with various bacteria, viruses, and protozoa likely will prove critical in designing new therapies. This article surveys our understanding of transporters that are modulated by specific pathogens and the mechanism(s) involved, thereby illuminating targets that might be exploited for new therapeutic approaches.

Hyperkalemia Was an Independent Risk Factor for Death While Under Mechanical Ventilation Among Children Hospitalized With Diarrhea in Bangladesh

Objectives. We sought to evaluate the admission and hospital risk factors for death in children with diarrhea requiring mechanical ventilation (MV). Methods. This was a retrospective study. We enrolled children aged 0 to 59 months admitted with diarrhea to the intensive care unit of the Dhaka Hospital of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) between August 2009 and July 2013 and required MV. To evaluate the risk factors for death in MV, we compared the clinical and laboratory characteristics of the children requiring MV. We matched up to the clinical characteristics presented on admission and subsequently developed before MV during hospital stay with the survivors and deaths of children having MV. Results. Among 73 enrolled children, 58 (80%) died. Incidence of death in MV was higher among children having hyperkalemia (P ≤ .001), hypoglycemia (P ≤ .001), and metabolic acidosis (P = .06) on admission and lower in children having tracheal isolates (P ≤ .001) during hospitalization. After adjusting for covariates by using multivariate robust Poisson regression, children with hyperkalemia (incidence ratio = 1.34; P = .03; confidence interval = 1.02-1.76) on admission was the only independent risk factor for death of children with MV. Conclusion. Children with hyperkalemia on admission and subsequently requiring MV were more likely to die compared with those without hyperkalemia.

Age specific fast breathing in under-five diarrheal children in an urban hospital: Acidosis or pneumonia?

Background

Children with diarrhea often present with fast breathing due to metabolic acidosis from dehydration. On the other hand, age specific fast breathing is the cornerstone for the diagnosis of pneumonia following classification of pneumonia recommended by the World Health Organization (WHO). Correction of metabolic acidosis by rehydrating the diarrheal children requires time, which delays early initiation of appropriate antimicrobials for pneumonia and thereby increases the risk of deaths. We need to further investigate the simple clinical features other than fast breathing which might help us in earliest diagnosis of pneumonia in children with diarrhea Thus, the objective of our study was to identify other contributing clinical features that may independently help for early diagnosis of pneumonia in diarrheal children who present with age specific fast breathing.

Methods

This was an unmatched case-control study. Diarrheal children aged 0–59 months, admitted to Dhaka Hospital of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) during January 2014 to December 2014 having age specific fast breathing (<2 month ≥60 breath/min, 2–11 months ≥50 breaths/min, >11–59 months ≥40 breaths/min) were studied. The study children with clinical and radiological pneumonia constituted the cases (n = 276) and those without pneumonia constituted the controls (n = 446). Comparison of clinical features and outcomes between the cases and the controls was made.

Results

The distribution of acidosis among the cases and the controls was comparable (35% vs. 41%, p = 0.12). The cases had proportionately higher deaths compared to the controls, however, the difference was not statistically significant (3% vs. 1%; p = 0.23). In logistic regression analysis after adjusting for potential confounders, the cases were independently associated with cough (OR = 62.19, 95% CI = 27.79–139.19; p<0.01) and chest wall indrawing (OR = 31.05, 95%CI = 13.43–71.82; p<0.01) and less often had severe acute malnutrition (OR = 0.33, 95%CI = 0.13–0.79; p<0.01). The sensitivity and specificity of cough were 83% (78–87%) and 93% (91–96%). The sensitivity and specificity for lower chest wall indrawing were 65% (59–71%) and 95% (93–97%). However, the sensitivity and specificity of cough and lower chest wall indrawing combined were 94% (89–97%) and 99% (97–100%).

Conclusion and significance

Thus, diarrheal children having fast breathing who present with cough and/or lower chest wall indrawing, irrespective of presence or absence of metabolic acidosis, are more likely to have radiological pneumonia. The results underscore the importance of early identification of these simple clinical features that may help to minimize potential delay due to rehydration in initiating prompt treatment of pneumonia in order to reduce fatal consequences in such children.

Cholera

Cholera is an acute, watery diarrhoeal disease caused by Vibrio cholerae of the O1 or O139 serogroups. In the past two centuries, cholera has emerged and spread from the Ganges Delta six times and from Indonesia once to cause global pandemics. Rational approaches to the case management of cholera with oral and intravenous rehydration therapy have reduced the case fatality of cholera from more than 50% to much less than 1%. Despite improvements in water quality, sanitation, and hygiene, as well as in the clinical treatment of cholera, the disease is still estimated to cause about 100 000 deaths every year. Most deaths occur in cholera-endemic settings, and virtually all deaths occur in developing countries. Contemporary understanding of immune protection against cholera, which results from local intestinal immunity, has yielded safe and protective orally administered cholera vaccines that are now globally stockpiled for use in the control of both epidemic and endemic cholera.

Tissue compartmentalization of T cell responses during early life

The immune system in early life is tasked with transitioning from a relatively protected environment to one in which it encounters a wide variety of innocuous antigens and dangerous pathogens. The immaturity of the developing immune system, and particularly the distinct functionality of T lymphocytes in early life, has been implicated in increased susceptibility to infection. Previous work has demonstrated that immune responses in early life are skewed toward limited inflammation and atopy; however, there is mounting evidence that such responses are context- and tissue-dependent. The regulation, differentiation, and maintenance of infant T cell responses, particularly as it relates to tissue compartmentalization, remains poorly understood. How the tissue environment impacts early-life immune responses and whether the development of localized protective immune memory cell subsets are established is an emerging area of research. As infectious diseases affecting the respiratory and digestive tracts are a leading cause of morbidity and mortality worldwide in infants and young children, a deeper understanding of site-specific immunity is essential to addressing these challenges. Here, we review the current paradigms of T cell responses during infancy as they relate to tissue localization and discuss implications for the development of vaccines and therapeutics.

Hypoxaemia and septic shock were independent risk factors for mechanical ventilation in Bangladeshi children hospitalised for diarrhoea

AIM

In Bangladesh, approximately 6% of children under five years of age die due to diarrhoea. We evaluated the admission and hospitalisation risk factors for mechanical ventilation and outcomes in children with diarrhoea.

METHODS

This retrospective case-control chart analysis was conducted in the intensive care unit of Dhaka Hospital of International Centre for Diarrhoeal Disease Research, Bangladesh. We enrolled 219 children with diarrhoea aged 0-59 months between August 2009 and July 2013. The 73 cases were children who were initially identified as requiring mechanical ventilation during the study period, and the 146 controls were randomly selected from those who did not require mechanical ventilation. We compared the groups to determine the risk factors for mechanical ventilation.

RESULTS

Mortality was significantly higher among the cases than the controls (p < 0.001). In the logistic regression analysis carried out for two separate time points, the independent risk factors for mechanical ventilation on admission were hypoxaemia (p < 0.001) and septic shock (p = 0.004) and during hospitalisation, they were intake of intravenous fluid (p = 0.015), hypokalaemia (p = 0.018), hyperkalaemia (p = 0.005) and septic shock (p = 0.001).

CONCLUSION

Children under five with diarrhoea who required mechanical ventilation frequently had hypoxaemia and septic shock and were more likely to die than unventilated controls.

Clinical risk factors, bacterial aetiology, and outcome of urinary tract infection in children hospitalized with diarrhoea in Bangladesh

Urinary tract infection (UTI) is common in children aged <5 years with diarrhoea, but little is known about risk factors, aetiology and outcome of such children. We aimed to evaluate these knowledge gaps of UTI in children aged <5 years with diarrhoea. We enrolled all children aged <5 years with diarrhoea admitted to Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, between May 2011 and April 2013, who had history of fever (⩾38 °C) and obtained a urine sample for culture. Diarrhoea with UTI (confirmed by culture) constituted cases (n = 26) and those without UTI constituted controls (n = 78). Threefold controls were randomly selected. The case-fatality rate was comparable in cases and controls (4% vs. 1%, P = 0·439). Escherichia coli (69%) and Klebsiella (15%) were the most commonly isolated pathogens. Persistent diarrhoea, pneumonia and prior antibiotics use were identified as risk factors for UTI in logistic regression analysis (P < 0·05 for all). Thus, children with diarrhoea presenting with persistent diarrhoea, pneumonia, and prior antibiotic use should be investigated for UTI for their prompt management that may reduce morbidity.

Experience with Clinically Diagnosed Down Syndrome Children Admitted with Diarrhea in an Urban Hospital in Bangladesh

There is lack of information in the medical literature on clinically diagnosed Down syndrome children presenting with diarrhea. Our aim was to describe our experience with Down syndrome patients admitted with diarrhea by evaluating the factors associated with Down syndrome presenting with diarrheal illness. In this retrospective chart analysis, we enrolled all the diarrheal children aged 0-59 months admitted to the Dhaka Hospital of the International Centre for Diarrheal Disease Research, Bangladesh (icddr, b), from March 2011 to February 2013. Down syndrome children with diarrhea constituted cases and randomly selected threefold diarrheal children without Down syndrome constituted controls. Among 8422 enrolled children 32 and 96 were the cases and the controls, respectively. Median age (months) of the cases and the controls was comparable (7.6 (4.0, 15.0) versus 9.0 (5.0, 16.8); p = 0.496). The cases more often presented with severe acute malnutrition, developmental delay, congenital heart disease, hypothyroidism, sepsis, hypocalcemia, developed hospital acquired infection (HAI) during hospitalization, and required prolonged stay at hospital compared to the controls (for all p < 0.05). Thus, diarrheal children with clinically diagnosed Down syndrome should be investigated for these simple clinical parameters for their prompt management that may prevent HAI and prolonged hospital stay.

Efficacy of partially hydrolyzed guar gum (PHGG) supplemented modified oral rehydration solution in the treatment of severely malnourished children with watery diarrhoea: a randomised double-blind controlled trial

OBJECTIVES

To examine whether PHGG added ORS reduce duration of diarrhoea, stool output and enhance weight gain.

METHODS

In a double-blind controlled clinical trial, 126 malnourished children (weight for length/weight for age < -3 Z-score with or without pedal edema), aged 6 - 36 months with acute diarrhoea <7 days were studied in two treatment groups; 63 received modified WHO ORS (Na 75, K 40, Cl 87, citrate 7, glucose 90 mmol/L) with PHGG 15 g/L (study group); 63 received modified WHO ORS without PHGG (control). Other treatments were similar in both groups. The study protocol was approved by Ethics Committee of icddr,b; the study was carried out at the Dhaka Hospital.

RESULTS

The mean duration of diarrhoea (h) was significantly shorter in children of the study group (Study vs. control, mean ± SD, 57 ± 31 vs. 75 ± 39, p = 0.01). Although there was a trend in stool weight reduction in children receiving ORS with PHGG (study vs. control, stool weight (g), mean ± SD; 1(st) 24 hour, 854.03 ± 532.15 vs. 949.11 ± 544.33, p = 0.32; 2(nd) 24 hour, 579.84 ± 466.01 vs. 761.26 ± 631.64, p = 0.069; 3(rd) 24 hour, 385.87 ± 454.09 vs. 495.73 ± 487.61, p = 0.196), especially in 2(nd) 24 h period, the difference was not statistically significant. The mean time (day) to attain weight for length 80% of NCHS median without edema was significantly shorter in the study group (study vs. control, mean ± SD, 4.5 ± 2.6 vs. 5.7 ± 2.8, p = 0.027).

CONCLUSION

PHGG added to ORS substantially reduced duration of diarrhoea. It also enhanced weight gain. Further studies might substantiate to establish its beneficial effect.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01821586.

Conservation and immunogenicity of novel antigens in diverse isolates of enterotoxigenic Escherichia coli

Background

Enterotoxigenic Escherichia coli (ETEC) are common causes of diarrheal morbidity and mortality in developing countries for which there is currently no vaccine. Heterogeneity in classical ETEC antigens known as colonization factors (CFs) and poor efficacy of toxoid-based approaches to date have impeded development of a broadly protective ETEC vaccine, prompting searches for novel molecular targets.

Methodology

Using a variety of molecular methods, we examined a large collection of ETEC isolates for production of two secreted plasmid-encoded pathotype-specific antigens, the EtpA extracellular adhesin, and EatA, a mucin-degrading serine protease; and two chromosomally-encoded molecules, the YghJ metalloprotease and the EaeH adhesin, that are not specific to the ETEC pathovar, but which have been implicated in ETEC pathogenesis. ELISA assays were also performed on control and convalescent sera to characterize the immune response to these antigens. Finally, mice were immunized with recombinant EtpA (rEtpA), and a protease deficient version of the secreted EatA passenger domain (rEatAp_H134R) to examine the feasibility of combining these molecules in a subunit vaccine approach.

Principal Findings

EtpA and EatA were secreted by more than half of all ETEC, distributed over diverse phylogenetic lineages belonging to multiple CF groups, and exhibited surprisingly little sequence variation. Both chromosomally-encoded molecules were also identified in a wide variety of ETEC strains and YghJ was secreted by 89% of isolates. Antibodies against both the ETEC pathovar-specific and conserved E. coli antigens were present in significantly higher titers in convalescent samples from subjects with ETEC infection than controls suggesting that each of these antigens is produced and recognized during infection. Finally, co-immunization of mice with rEtpA and rEatAp_H134R offered significant protection against ETEC infection.

Conclusions

Collectively, these data suggest that novel antigens could significantly complement current approaches and foster improved strategies for development of broadly protective ETEC vaccines.

Infectious diarrhea is one of the leading causes of death among young children in developing countries, and a major cause of morbidity in all age groups. The enterotoxigenic Escherichia coli contribute substantially to this burden of diarrheal illness, and have been a focus of vaccine development efforts for more than forty years following their discovery as a cause of severe diarrheal illness. The heat-labile, and/or heat stable enterotoxins that define ETEC are produced by a diverse population of Escherichia coli. This inherent genetic plasticity of E. coli has made it difficult to identify antigens specific to ETEC that are highly conserved. Therefore, identification of protective antigens shared by many ETEC strains will likely play an essential role in development of the next iteration of vaccines.

Aetiologies of diarrhoea in adults from urban and rural treatment facilities in Bangladesh

The objective of our analysis was to describe the aetiology, clinical features, and socio-demographic background of adults with diarrhoea attending different urban and rural diarrhoeal disease hospitals in Bangladesh. Between January 2010 and December 2011, a total of 5054 adult diarrhoeal patients aged ⩾20 years were enrolled into the Diarrhoeal Disease Surveillance Systems at four different hospitals (two rural and two urban) of Bangladesh. Middle-aged [adjusted odds ratio (aOR) 0·28, 95% confidence interval (CI) 0·23-0·35, P < 0·001] and elderly (aOR 0·15, 95% CI 0·11-0·20, P < 0·001) patients were more likely to present to rural diarrhoeal disease facilities than urban ones. Vibrio cholerae was the most commonly isolated pathogen (16%) of the four pathogens tested followed by rotavirus (5%), enterotoxigenic Escherichia coli (ETEC) (4%), and Shigella (4%). Of these pathogens, V. cholerae (19% vs. 11%, P < 0·001), ETEC (9% vs. 4%, P < 0·001), and rotavirus (5% vs. 3%, P = 0·013) were more commonly detected from patients presenting to urban hospitals than rural hospitals, but Shigella was more frequently isolated from patients presenting to rural hospitals than urban hospitals (7% vs. 2%, P < 0·001). The isolation rate of Shigella was higher in the elderly than in younger adults (8% vs. 3%, P < 0·001). Some or severe dehydration was higher in urban adults than rural adults (P < 0·001). Our findings indicate that despite economic and other progress made, conditions facilitating transmission of V. cholerae and Shigella prevail in adults with diarrhoea in Bangladesh and further efforts are needed to control these infections.

Specialist hospital study shows that septic shock and drowsiness predict mortality in children under five with diarrhoea

AIM

To evaluate the clinical characteristics and outcome in children hospitalised with diarrhoea, comparing those developed septic shock with those who did not.

METHODS

We carried out a retrospective chart review on children aged 0-59 months admitted to the Dhaka Hospital, International Centre for Diarrhoeal Diseases Research, Bangladesh, with diarrhoea between October 2010 and September 2011. They were included if they had severe sepsis defined as tachycardia plus hyperthermia or hypothermia or an abnormal white blood cell count plus poor peripheral perfusion in absence of dehydration. Patients unresponsive to fluid and boluses, who required inotropes, were categorised as having septic shock (n = 88). The controls were those without septic shock (n = 116).

RESULTS

Death was significantly higher among the children with septic shock (67%) than the controls (14%) (p < 0.001). A logistic regression analysis, adjusted for potential confounders, found that children with septic shock were more likely to be drowsy on admission and received blood transfusions and mechanical ventilation (all p < 0.05).

CONCLUSION

Children hospitalised for diarrhoea with septic shock were more likely to die, be drowsy on admission and receive blood transfusions and mechanical ventilation. A randomised clinical trial on inotropes in children with diarrhoea, severe sepsis and drowsiness may expedite their use and prevent mechanical ventilation and deaths.

Lack of BCG vaccination and other risk factors for bacteraemia in severely malnourished children with pneumonia

We sought to examine the factors associated with bacteraemia and their outcome in children with pneumonia and severe acute malnutrition (SAM). All SAM children of either sex, aged 0-59 months, admitted to the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh with radiologically confirmed pneumonia from April 2011 to July 2012 were enrolled (n = 405). Comparison was made between pneumonic SAM children with (cases = 18), and without (controls = 387) bacteraemia. The death rate was significantly higher in cases than controls (28% vs. 8%, P < 0·01). In logistic regression analysis, after adjusting for potential confounders, the SAM children with pneumonia and bacteraemia more often had a history of lack of bacillus Calmette-Guérin (BCG) vaccination (odds ratio 7·39, 95% confidence interval 1·67-32·73, P < 0·01). The results indicate the importance of continuation of BCG vaccination which may provide benefit beyond its primary purpose.

Clinical risk factors of death from pneumonia in children with severe acute malnutrition in an urban critical care ward of Bangladesh

Background

Risks of death are high when children with pneumonia also have severe acute malnutrition (SAM) as a co-morbidity. However, there is limited published information on risk factors of death from pneumonia in SAM children. We evaluated clinically identifiable factors associated with death in under-five children who were hospitalized for the management of pneumonia and SAM.

Methods

For this unmatched case-control design, SAM children of either sex, aged 0–59 months, admitted to the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) during April 2011 to July 2012 with radiological pneumonia were studied. The SAM children with pneumonia who had fatal outcome constituted the cases (n = 35), and randomly selected SAM children with pneumonia who survived constituted controls (n = 105).

Results

The median (inter-quartile range) age (months) was comparable among the cases and the controls [8.0 (4.9, 11.0) vs. 9.7 (5.0, 18.0); p = 0.210)]. In logistic regression analysis, after adjusting for potential confounders, such as vomiting, abnormal mental status, and systolic hypotension (<70 mm of Hg) in absence of dehydration, fatal cases of severely malnourished under-five children with pneumonia were more often hypoxemic (OR = 23.15, 95% CI = 4.38–122.42), had clinical dehydration (some/severe) (OR = 9.48, 95% CI = 2.42–37.19), abdominal distension at admission (OR = 4.41, 95% CI = 1.12–16.52), and received blood transfusion (OR = 5.50, 95% CI = 1.21–24.99) for the management of crystalloid resistant systolic hypotension.

Conclusion and Significance

We identified hypoxemia, clinical dehydration, and abdominal distension as the independent predictors of death in SAM children with pneumonia. SAM children with pneumonia who required blood transfusion for the management of crystalloid resistant systolic hypotension were also at risk for death. Thus, early identification and prompt management of these simple clinically recognizable predictors of death and discourage the use of blood transfusion for the management of crystalloid resistant systolic hypotension may help reduce deaths in such population.

Predictors and outcome of hypoxemia in severely malnourished children under five with pneumonia: a case control design

BACKGROUND

There is lack of information in the medical literature on predictors of hypoxemia in severely malnourished children with pneumonia, although hypoxemia is common and is often associated with fatal outcome in this population. We explored the predictors of hypoxemia in under-five children who were hospitalized for the management of pneumonia and severe acute malnutrition (SAM).

METHODS

In this unmatched case-control design, SAM children of both sexes, aged 0-59 months, admitted to the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B) with radiological pneumonia and hypoxemia during April 2011 to April 2012 were studied. SAM children with pneumonia and hypoxemia (SpO(2)<90%) constituted the cases (n = 37), and randomly selected SAM children with pneumonia but without hypoxemia constituted controls (n = 111).

RESULTS

The case-fatality was significantly higher among the cases than the controls (30% vs. 4%; p<0.001). In logistic regression analysis, after adjusting for potential confounders such as nasal flaring, head nodding, inability to drink, and crackles in lungs, fast breathing (95% CI = 1.09-13.55), lower chest wall in-drawing (95% CI = 2.48-43.41), and convulsion at admission (95% CI = 3.14-234.01) were identified as independent predictors of hypoxemia in this population. The sensitivity of fast breathing, lower chest wall in-drawing and convulsion at admission and their 95% confidence intervals (CI) to predict hypoxemia were 84 (67-93)%, 89 (74-96)%, and 19 (9-36)% respectively, and their specificity were 53 (43-63)%, 60 (51-69)% and 98 (93-100)% respectively.

CONCLUSION AND SIGNIFICANCE

Fast breathing and lower chest wall in-drawing were the best predictors of hypoxemia in SAM children with pneumonia. There thus, in resources poor settings where pulse oximetry is not available, identification of these simple clinical predictors of hypoxemia in such children could be reliably used for early O(2) supplementation in addition to other appropriate management to reduce morbidity and deaths.

Clinical predictors and outcome of metabolic acidosis in under-five children admitted to an urban hospital in Bangladesh with diarrhea and pneumonia

Background

Clinical features of metabolic acidosis and pneumonia frequently overlap in young diarrheal children, resulting in differentiation from each other very difficult. However, there is no published data on the predictors of metabolic acidosis in diarrheal children also having pneumonia. Our objective was to evaluate clinical predictors of metabolic acidosis in under-five diarrheal children with radiological pneumonia, and their outcome.

Methods

We prospectively enrolled all under-five children (n = 164) admitted to the Special Care Ward (SCW) of the Dhaka Hospital of icddr, b between September and December 2007 with diarrhea and radiological pneumonia who also had their total serum carbon-dioxide estimated. We compared the clinical features and outcome of children with radiological pneumonia and diarrhea with (n = 98) and without metabolic acidosis (n = 66).

Results

Children with metabolic acidosis more often had higher case-fatality (16% vs. 5%, p = 0.039) compared to those without metabolic acidosis on admission. In logistic regression analysis, after adjusting for potential confounders such as age of the patient, fever on admission, and severe wasting, the independent predictors of metabolic acidosis in under-five diarrheal children having pneumonia were clinical dehydration (OR 3.57, 95% CI 1.62–7.89, p = 0.002), and low systolic blood pressure even after full rehydration (OR 1.02, 95% CI 1.01–1.04, p = 0.005). Proportions of children with cough, respiratory rate/minute, lower chest wall indrawing, nasal flaring, head nodding, grunting respiration, and cyanosis were comparable (p>0.05) among the groups.

Conclusion and Significance

Under-five diarrheal children with radiological pneumonia having metabolic acidosis had frequent fatal outcome than those without acidosis. Clinical dehydration and persistent systolic hypotension even after adequate rehydration were independent clinical predictors of metabolic acidosis among the children. However, metabolic acidosis in young diarrheal children had no impact on the diagnostic clinical features of radiological pneumonia which underscores the importance of early initiation of appropriate antibiotics to combat morbidity and deaths in such population.

Co-morbidity: exploring the clinical overlap between pneumonia and diarrhoea in a hospital in Dhaka, Bangladesh

BACKGROUND

There is limited information on risk factors for pneumonia and pneumonia-related deaths in children who also have diarrhoea.

AIM

To identify risk factors for the above in order to improve strategies for case management and to develop appropriate public health messages.

METHODS

All children under 5 years of age admitted to the Special Care Ward, Dhaka Hospital of the International Centre for Diarrhoeal Disease Research (ICDDR,B) from 1 September to 31 December 2007 were considered for enrollment if they also had diarrhoea. Of the 258 children with diarrhoea enrolled, those with (n=198) or without (n=60) WHO-defined pneumonia constituted the pneumonia and comparison groups, respectively. Among the 198 children with pneumonia, children who survived (n=174) were compared with those who died in hospital (n=24).

RESULTS

After adjusting for socio-demographic factors, including low levels of literacy of either parent, low household income, not having a window or exhaust fan in the kitchen, household smoking and over-crowding, children with pneumonia were more likely to sleep on a bare wooden-slatted or bamboo bed (OR 2·7, 95% CI 1·40-5·21, p = 0·003) than on other bedding, and were also more likely to have a parent/care-giver with poor knowledge of pneumonia (OR 1·94, 95% CI 1·02-3·70, p=0·043). Independent risk factors for death include severe underweight (OR 5·2, 95% CI 1·2-22·0, p=0·03), hypoxaemia (OR 17·5, 95% CI I 1·9-160·0, p=0·01), severe sepsis (OR 8·7, 95% CI I 1·8-41·5, p=0·007) and lobar consolidation (OR 11·9, 95% CI 2·3-61·6, p=0·003).

CONCLUSIONS

Increased public awareness of signs of pneumonia and severe sepsis in children under 5 is important to mitigate the risks of pneumonia and pneumonia-related deaths, and the importance of appropriate bedding for young children in reducing the risk of pneumonia needs to be addressed.

Probiotic, zinc and lactose-free formula in children with rotavirus diarrhea: are they effective?

BACKGROUND

The aim of the present study was to evaluate the effectiveness of zinc, probiotic bacteria, and lactose-free formula and their different combinations in the treatment of rotavirus diarrhea in young children.

METHODS

Eight different treatment groups were formed: group 1, 60 patients receiving Saccharomyces boulardii; group 2, 60 patients receiving zinc; group 3, 60 patients receiving lactose-free formula; group 4, 60 patients receiving S. boulardii plus zinc; group 5, 60 patients receiving S. boulardii plus lactose-free formula; group 6, 60 patients receiving zinc plus lactose-free formula; group 7, 60 patients receiving S. boulardii plus zinc plus lactose-free formula; group 8, 60 patients receiving only oral and/or parenteral rehydration solutions.

RESULTS

No statistically significant differences were found in the time to resolution of fever after intervention between the treatment groups and the control group. The time to resolution of vomiting was significantly lower in group 4 compared with groups 1 and 5. The duration of diarrhea was significantly reduced in groups 2 and 4 compared to control. A statistically significant difference in the duration of hospitalization was observed for the groups 2 and 4 in comparison to the control group.

CONCLUSIONS

A different combination of adjunct therapies did not seem to bring additional value to rehydration therapy in children with rotavirus diarrhea except for in those receiving only zinc and zinc plus S. boulardii. Further studies are required to determine the optimal protocol of adjunct therapy use in children with rotavirus diarrhea.

Clinical predictors and outcome of hypoxaemia among under-five diarrhoeal children with or without pneumonia in an urban hospital, Dhaka, Bangladesh

OBJECTIVE

To explore the predictors and outcome of hypoxaemia in children under 5 years of age who were hospitalized for the management of diarrhoea in Dhaka, where comorbidities are common.

METHODS

In a prospective cohort study, we enrolled all children <5 years of age admitted to the special care ward (SCW) of the Dhaka Hospital of ICDDR,B from September to December 2007. Those who presented with hypoxaemia (SpO(2) < 90%) constituted the study group, and those without hypoxaemia formed the comparison group.

RESULTS

A total of 258 children were enrolled, all had diarrhoea. Of the total, 198 (77%) had pneumonia and 106 (41%) had severe malnutrition (<-3 Z-score of weight for age of the median of the National Centre for Health Statistics), 119 (46%) had hypoxaemia and 138 children did not have hypoxaemia at the time of admission. Children with hypoxaemia had a higher probability of a fatal outcome (21%vs. 4%; P < 0.001). Using logistic regression analysis, the independent predictors of hypoxaemia at the time of presentation were lower chest wall indrawing [OR 6.91, 95% confidence intervals (CI) 3.66-13.08, P < 0.001], nasal flaring (OR 3.22, 95% CI 1.45-7.17, P = 0.004) and severe sepsis (OR 4.48, 95% CI 1.62-12.42, P = 0.004).

CONCLUSION

In this seriously ill population of children with diarrhoea and comorbidities, hypoxaemia was associated with high case-fatality rates. Independent clinical predictors of hypoxaemia in this population, identifiable at the time of admission, were lower chest wall indrawing, nasal flaring and the clinical syndrome of severe sepsis.

Clonal transmission, dual peak, and off-season cholera in Bangladesh

Vibrio cholerae is an estuarine bacterium associated with a single peak of cholera (March–May) in coastal villages of Bangladesh. For an unknown reason, however, cholera occurs in a unique dual peak (March–May and September–November) pattern in the city of Dhaka that is bordered by a heavily polluted freshwater river system and flood embankment. In August 2007, extreme flooding was accompanied by an unusually severe diarrhea outbreak in Dhaka that resulted in a record high illness. This study was aimed to understand the unusual outbreak and if it was related to the circulation of a new V. cholerae clone. Nineteen V. cholerae isolated during the peak of the 2007 outbreak were subjected to extensive phenotypic and molecular analyses, including multi-locus genetic screening by polymerase chain reaction (PCR), sequence-typing of the ctxB gene, and pulsed-field gel electrophoresis (PFGE). Factors associated with the unusual incidence of cholera were determined and analysis of the disease severity was done. Overall, microbiological and molecular data confirmed that the hypervirulent V. cholerae was O1 biotype El Tor (ET) that possessed cholera toxin (CT) of the classical biotype. The PFGE (NotI) and dendrogram clustering confirmed that the strains were clonal and related to the pre-2007 variant ET from Dhaka and Matlab and resembled one of two distinct clones of the variant ET confirmed to be present in the estuarine ecosystem of Bangladesh. Results of the analyses of both diarrheal case data for three consecutive years (2006–2008) and regional hydroclimatology over three decades (1980–2009) clearly indicate that the pattern of cholera occurring in Dhaka, and not seen at other endemic sites, was associated with flood waters transmitting the infectious clone circulating via the fecal-oral route during and between the dual seasonal cholera peaks in Dhaka. Circular river systems and flood embankment likely facilitate transmission of infectious V. cholerae throughout the year that leads to both sudden and off-season outbreaks in the densely populated urban ecosystem of Dhaka. Clonal recycling of hybrid El Tor with increasing virulence in a changing climate and in a region with a growing urban population represents a serious public health concern for Bangladesh.

Potential beneficial effects of butyrate in intestinal and extraintestinal diseases

The multiple beneficial effects on human health of the short-chain fatty acid butyrate, synthesized from non-absorbed carbohydrate by colonic microbiota, are well documented. At the intestinal level, butyrate plays a regulatory role on the transepithelial fluid transport, ameliorates mucosal inflammation and oxidative status, reinforces the epithelial defense barrier, and modulates visceral sensitivity and intestinal motility. In addition, a growing number of studies have stressed the role of butyrate in the prevention and inhibition of colorectal cancer. At the extraintestinal level, butyrate exerts potentially useful effects on many conditions, including hemoglobinopathies, genetic metabolic diseases, hypercholesterolemia, insulin resistance, and ischemic stroke. The mechanisms of action of butyrate are different; many of these are related to its potent regulatory effects on gene expression. These data suggest a wide spectrum of positive effects exerted by butyrate, with a high potential for a therapeutic use in human medicine.

Influences of dehydration on clinical features of radiological pneumonia in children attending an urban diarrhoea treatment centre in Bangladesh

BACKGROUND

As the signs of dehydration often overlap with those of pneumonia, it may be difficult for health workers in resource-poor settings to make a clinical diagnosis of pneumonia in children with dehydration. This issue has received very little attention.

AIM

To compare the clinical features of pneumonia in children with and without dehydration caused by diarrhoea.

METHODS

All children aged 2-59 months with diarrhoea and radiologically confirmed pneumonia admitted to the Special Care Ward (SCW) of Dhaka Hospital, ICDDR,B between September and December 2007 were enrolled for the study. Children with dehydration (67 cases) and those without (101 controls) were compared.

RESULTS

Cases presented less frequently with fast breathing (60% vs 88%, p<0.001) and lower chest-wall indrawing (67% vs 82%, p=0.035) than did controls. In logistic regression analysis, cases more often had severe malnutrition (OR 2.31, CI 1.06-5.02, p=0.035) and cyanosis (OR 19.05, CI 1.94-186.68, p=0.011) and were abnormally sleepy (OR 372, CI 1.71-8.08, p=0.001).

CONCLUSIONS

Fast breathing and lower chest-wall indrawing may be less reliable for the diagnosis of pneumonia in children with dehydration, especially when there is severe malnutrition.

Diagnostic limitations to accurate diagnosis of cholera

The treatment regimen for diarrhea depends greatly on correct diagnosis of its etiology. Recent diarrhea outbreaks in Bangladesh showed Vibrio cholerae to be the predominant cause, although more than 40% of the suspected cases failed to show cholera etiology by conventional culture methods (CMs). In the present study, suspected cholera stools collected from every 50th patient during an acute diarrheal outbreak were analyzed extensively using different microbiological and molecular tools to determine their etiology. Of 135 stools tested, 86 (64%) produced V. cholerae O1 by CMs, while 119 (88%) tested positive for V. cholerae O1 by rapid cholera dipstick (DS) assay; all but three samples positive for V. cholerae O1 by CMs were also positive for V. cholerae O1 by DS assay. Of 49 stools that lacked CM-based cholera etiology despite most being positive for V. cholerae O1 by DS assay, 25 (51%) had coccoid V. cholerae O1 cells as confirmed by direct fluorescent antibody (DFA) assay, 36 (73%) amplified primers for the genes wbe O1 and ctxA by multiplex-PCR (M-PCR), and 31 (63%) showed El Tor-specific lytic phage on plaque assay (PA). Each of these methods allowed the cholera etiology to be confirmed for 97% of the stool samples. The results suggest that suspected cholera stools that fail to show etiology by CMs during acute diarrhea outbreaks may be due to the inactivation of V. cholerae by in vivo vibriolytic action of the phage and/or nonculturability induced as a host response.

Prevention of rotavirus gastroenteritis in infants and children: rotavirus vaccine safety, efficacy, and potential impact of vaccines

Rotavirus infection is the most common cause of severe gastroenteritis globally, with greater than 86% of deaths occurring in low-income and middle-income countries. There are two rotavirus vaccines currently licensed in the United States and prequalified by the World Health Organization. RV1 is a monovalent attenuated human rotavirus strain, given orally in two doses. RV5 is a pentavalent human-bovine reassortant rotavirus vaccine, given orally in three doses. A third rotavirus vaccine, LLV, is a lamb rotavirus strain given orally as a single dose, which is currently available only in China. RV1 and RV5 have been shown to be highly efficacious in developed countries, and initial results from trials in Africa and Asia are promising as well. At least three other vaccines are in development, which are being developed by manufacturers of developing countries. Further studies are needed to clarify issues including administration of oral rotavirus vaccines with breastfeeding and other oral vaccines, and alterations in dosing schedule. Using new data on global diarrheal burden, rotavirus is estimated to cause 390,000 deaths in children younger than 5 years. Should rotavirus vaccines be introduced in the routine immunization programs of all countries, a potential of 170,000 deaths could be prevented annually. The largest impact on mortality would be seen in low-income and middle-income countries, despite poor immunization coverage and lower efficacy. Therefore, international efforts are needed to ensure that rotavirus vaccines reach the populations with highest burden of rotavirus disease.

Antimicrobial resistance in Campylobacter coli selected by tylosin treatment at a pig farm

Limited knowledge is available regarding the dynamics of macrolide resistance under farm conditions with natural Campylobacter populations. We examined the dynamics of antimicrobial resistance in Campylobacter coli at a large pig farm. Faeces were sampled from untreated sows and piglets (n=57), weaned pigs treated with tylosin (n=68) and pigs of the same group 3-5 weeks after withdrawal of tylosin (n=15). Additionally, 48 weaned pigs were sampled after tylosin had not been administered for 7 months at the farm. MICs for seven antimicrobials were determined, isolates were genotyped by PFGE and mutations conferring macrolide resistance were identified. Resistance to at least one antimicrobial agent was higher (P<0.001) in the isolates from the treated pigs (30 of 56) than in those from the untreated animals (2 of 40). Resistance to ciprofloxacin, erythromycin, nalidixic acid and streptomycin was higher (P<0.05) in the isolates from the treated pigs than in those from the untreated animals. All 14 erythromycin-resistant isolates studied (MIC ≥ 512 μg/ml) contained mutation A2075G in 23S rRNA. Resistance against at least one antimicrobial was significantly lower (P<0.05) when tylosin had not been administered for 7 months. Resistance to erythromycin and streptomycin also decreased (P<0.05). PFGE analysis revealed a change of genotypes induced by tylosin treatment. In conclusion, tylosin treatment of pigs selected for a high-level of resistance to erythromycin and resistance to ciprofloxacin, nalidixic acid and streptomycin also increased in C. coli isolates within a few days.