Diarrhea in developed and developing countries: magnitude, special settings, and etiologies

Changing Epidemiology and Antimicrobial Resistance of Bacterial Childhood Diarrhea: Insights from a 7-Year Study in an Iranian Referral Hospital

Acute gastroenteritis (AGE) poses a significant public health challenge for children in developing countries. Considering the high prevalence of AGE in Iranian children, the aim of this study was to investigate and analyze the patterns and changes in bacterial identification as well as antibiotic resistance in AG over the course of 7 years. From January 2015 to December 2021, a total of 15,300 pediatric patients with AGE were admitted to the Children's Medical Center, an Iranian academic referral hospital, Tehran, Iran. Among these cases, 8.9% (1329 individuals) yielded positive stool cultures. The predominant bacterial etiology of AGE was identified as Shigella sonnei (n = 424, 31.9%), and Salmonella group D (n = 367, 27.6%), followed by Shigella flexneri: 16.3% (217 cases), Salmonella group C (n = 152, 11.4%), Salmonella group B (n = 91, 6.8%), Escherichia coli (n = 65, 4.9%), Shigella boydii (n = 10, 0.75%), and Shigella dysenteriae (n = 3, 0.2%). Notably, S. sonnei exhibited high resistance rates to trimethoprim-sulfamethoxazole (97.6%) and nalidixic acid (95.3%). S. flexneri and S. boydii isolates displayed significant resistance to ampicillin (96.8% and 88.9%, respectively). Salmonella group D demonstrated elevated resistance to ciprofloxacin (81.3%) and nalidixic acid (88.5%), with notable sensitivity to trimethoprim-sulfamethoxazole and cefotaxime (97.3% and 97.5%, respectively). E. coli displayed resistance rates of 80%, 74%, and 66% to trimethoprim-sulfamethoxazole, cefotaxime, and ciprofloxacin, respectively. The fluctuating prevalence of S. sonnei and Salmonella group D, two predominant bacterial isolates associated with AGE, underscores the dynamic nature of these pathogens. The notable increase in antibiotic resistance observed in S. sonnei raises concerns, underscoring the critical need for judicious and careful antibiotic use.

Bovine Colostrum in Pediatric Nutrition and Health

Bovine colostrum (BC), the first milk secreted by mammals after birth, is a trending alternative source for supplementing infants and children, offering benefits for gut and immune health. Its rich components, such as proteins, immunoglobulins, lactoferrin, and glycans, are used to fortify diets and support development. Preterm development is crucial, especially in the maturation of essential systems, and from 2010 to 2020, approximately 15% of all premature births occurred at less than 32 weeks of gestation worldwide. This review explores the composition, benefits, and effects of BC on general infants and children, along with preterm infants who require special care, and highlights its role in growth and development. BC is also associated with specific pediatric diseases, including necrotizing enterocolitis (NEC), infectious diarrhea, inflammatory bowel disease (IBD), short-bowel syndrome (SBS), neonatal sepsis, gastrointestinal and respiratory infections, and some minor conditions. This review also discusses the clinical trials regarding these specific conditions which are occasionally encountered in preterm infants. The anti-inflammatory, antimicrobial, immunomodulatory, and antiviral properties of BC are discussed, emphasizing its mechanisms of action. Clinical trials, particularly in humans, provide evidence supporting the inclusion of BC in formulas and diets, although precise standards for age, feeding time, and amounts are needed to ensure safety and efficacy. However, potential adverse effects, such as allergic reactions to caseins and immunoglobulin E, must be considered. More comprehensive clinical trials are necessary to expand the evidence on BC in infant feeding, and glycans, important components of BC, should be further studied for their synergistic effects on pediatric diseases. Ultimately, BC shows promise for pediatric health and should be incorporated into nutritional supplements with caution.

Forecasting of diarrhea disease using ARIMA model in Kendari City, Southeast Sulawesi Province, Indonesia

Background

In Indonesia, diarrhea is one of the endemic diseases that often leads to death. The high number of diarrhea cases has the potential to become an extraordinary event, thus requiring more serious attention. This research aims to analyze the data on recorded cases of diarrhea in the Health Department of Kendari City from January 2016 to June 2022.

Methods

The ARIMA model, commonly referred to as ARIMA (p, d, q), is used, where p represents the autoregressive terms, d indicates the non-seasonal differences required for achieving stationarity, and q denotes the lagged forecast errors in the prediction equation. To determine the order of the autoregressive (AR) and moving average (MA) components included in the ARIMA model, the patterns of the plot of the auto-correlation function (ACF) and the partial auto-correlation function (PACF) were utilized. Data analysis was carried out using Minitab Release 16 software.

Results

The forecast using this model indicates a decrease in diarrhea cases over the next two years, from July 2022 to June 2024. The forecast estimates a total of 1.971 diarrhea cases from July 2022 to June 2023 and 1.255 cases from July 2023 to June 2024.

Conclusions

The incidence of diarrhea in Kendari City fluctuates every year. This forecast provides an early warning to the government to take preventive measures against diarrhea. It is hoped that this system will reduce the negative impact of diarrhea in Kendari City.

Infectious etiologies of persistent and chronic diarrhea in Asian developing countries: A systematic review and meta-analysis

Infectious causes of diarrhea contribute significantly to morbidity in Asia. We conducted a systematic review and meta-analysis of the prevalence of infectious etiologies of persistent and chronic diarrhea in Asian adults. Searches were performed on PubMed and Scopus for studies from January 1, 1970, to May 30, 2023. Sixteen studies were identified and included. The meta-analysis was conducted with the random-effects method, estimating the pooled prevalence of groups of infectious pathogens as causes of persistent and chronic diarrhea among Asian adults. The findings were highly heterogeneous and indicative of publication bias. The majority of studies were conducted on persons living with human immunodeficiency virus infection (PLHIV). The studies were predominantly from low-income and middle-income Asian countries. The most common cause was parasitic, with a pooled prevalence of 0.52 (95% confidence interval 0.28-0.65, I2 = 99%, Cochran's Q = 1027.44, P < 0.01), followed by bacterial, fungal, and viral causes, which were substantially rarer. Negative microbiological testing was also common, with a pooled prevalence for a negative test being 0.37 (95% confidence interval 0.17-0.52, I2 = 99%, Cochran's Q = 1027.44, P < 0.01). Subgroup analyses of studies conducted among PLHIV, from year 2000 and among those conducted in Southeast Asia showed a similar prevalence of parasitic causes of diarrhea. In conclusion, in Asian adults with persistent and chronic diarrhea, parasitic causes were most prevalent. However, the estimate of true prevalence is limited by significant heterogeneity among the available studies. More study in this field is required, especially examining PLHIV in the post-antiretroviral therapy era and from high-income countries.

Establishment and perturbation of human gut microbiome: common trends and variations between Indian and global populations

Human gut microbial species are crucial for dietary metabolism and biosynthesis of micronutrients. Digested products are utilised by the host as well as several gut bacterial species. These species are influenced by various factors such as diet, age, geographical location, and ethnicity. India is home to the largest human population in the world. It is spread across diverse ecological and geographical locations. With variable dietary habits and lifestyles, Indians have unique gut microbial composition. This review captures contrasting and common trends of gut bacterial community establishment in infants (born through different modes of delivery), and how that bacterial community manifests itself along infancy, through old age between Indian and global populations. Because dysbiosis of the gut community structure is associated with various diseases, this review also highlights the common and unique bacterial species associated with various communicable as well as noncommunicable diseases such as diarrhoea, amoebiasis, malnutrition, type 2 diabetes, obesity, colorectal cancer, inflammatory bowel disease, and gut inflammation and damage to the brain in the global and Indian population.

Epidemiology of Rotavirus in Humans, Animals, and the Environment in Africa: A Systematic Review and Meta-analysis

BACKGROUND

Globally, rotavirus infections are the most common cause of diarrhea-related deaths, especially among children under 5 years of age. This virus can be transmitted through the fecal-oral route, although zoonotic and environmental contributions to transmission are poorly defined. The purpose of this study is to determine the epidemiology of rotavirus in humans, animals, and the environment in Africa, as well as the impact of vaccination.

METHODS

We searched PubMed, Web of Science, Africa Index Medicus, and African Journal Online, identifying 240 prevalence data points from 224 articles between 2009 and 2022.

RESULTS

Human rotavirus prevalence among patients with gastroenteritis was 29.8% (95% confidence interval [CI], 28.1%-31.5%; 238 710 participants), with similar estimates in children under 5 years of age, and an estimated case fatality rate of 1.2% (95% CI, .7%-2.0%; 10 440 participants). Prevalence was estimated to be 15.4% and 6.1% in patients with nongastroenteritis illnesses and apparently healthy individuals, respectively. Among animals, prevalence was 9.3% (95% CI, 5.7%-13.7%; 6115 animals), and in the environmental water sources, prevalence was 31.4% (95% CI, 17.7%-46.9%; 2530 samples).

DISCUSSION

Our findings highlight the significant burden of rotavirus infection in Africa, and underscore the need for a One Health approach to limiting the spread of this disease.

Balanced crystalloid solutions versus 0.9% saline for treating acute diarrhoea and severe dehydration in children

BACKGROUND

Although acute diarrhoea is a self-limiting disease, dehydration may occur in some children. Dehydration is the consequence of an increased loss of water and electrolytes (sodium, chloride, potassium, and bicarbonate) in liquid stools. When these losses are high and not replaced adequately, severe dehydration appears. Severe dehydration is corrected with intravenous solutions. The most frequently used solution for this purpose is 0.9% saline. Balanced solutions (e.g. Ringer's lactate) are alternatives to 0.9% saline and have been associated with fewer days of hospitalization and better biochemical outcomes. Available guidelines provide conflicting recommendations. It is unclear whether 0.9% saline or balanced intravenous fluids are most effective for rehydrating children with severe dehydration due to diarrhoea.

OBJECTIVES

To evaluate the benefits and harms of balanced solutions for the rapid rehydration of children with severe dehydration due to acute diarrhoea, in terms of time in hospital and mortality compared to 0.9% saline.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 4 May 2022.

SELECTION CRITERIA

We included randomized controlled trials in children with severe dehydration due to acute diarrhoea comparing balanced solutions, such as Ringer's lactate or Plasma-Lyte with 0.9% saline solution, for rapid rehydration.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. time in hospital and 2.

MORTALITY

Our secondary outcomes were 3. need for additional fluids, 4. total amount of fluids received, 5. time to resolution of metabolic acidosis, 6. change in and the final values of biochemical measures (pH, bicarbonate, sodium, chloride, potassium, and creatinine), 7. incidence of acute kidney injury, and 8.

ADVERSE EVENTS

We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

Characteristics of the included studies We included five studies with 465 children. Data for meta-analysis were available from 441 children. Four studies were conducted in low- and middle-income countries and one study in two high-income countries. Four studies evaluated Ringer's lactate, and one study evaluated Plasma-Lyte. Two studies reported the time in hospital, and only one study reported mortality as an outcome. Four studies reported final pH and five studies reported bicarbonate levels. Adverse events reported were hyponatremia and hypokalaemia in two studies each. Risk of bias All studies had at least one domain at high or unclear risk of bias. The risk of bias assessment informed the GRADE assessments. Primary outcomes Compared to 0.9% saline, the balanced solutions likely result in a slight reduction of the time in hospital (mean difference (MD) -0.35 days, 95% confidence interval (CI) -0.60 to -0.10; 2 studies; moderate-certainty evidence). However, the evidence is very uncertain about the effect of the balanced solutions on mortality during hospitalization in severely dehydrated children (risk ratio (RR) 0.33, 95% CI 0.02 to 7.39; 1 study, 22 children; very low-certainty evidence). Secondary outcomes Balanced solutions probably produce a higher increase in blood pH (MD 0.06, 95% CI 0.03 to 0.09; 4 studies, 366 children; low-certainty evidence) and bicarbonate levels (MD 2.44 mEq/L, 95% CI 0.92 to 3.97; 443 children, four studies; low-certainty evidence). Furthermore, balanced solutions likely reduces the risk of hypokalaemia after the intravenous correction (RR 0.54, 95% CI 0.31 to 0.96; 2 studies, 147 children; moderate-certainty evidence). Nonetheless, the evidence suggests that balanced solutions may result in no difference in the need for additional intravenous fluids after the initial correction; in the amount of fluids administered; or in the mean change of sodium, chloride, potassium, and creatinine levels.

AUTHORS' CONCLUSIONS

The evidence is very uncertain about the effect of balanced solutions on mortality during hospitalization in severely dehydrated children. However, balanced solutions likely result in a slight reduction of the time in the hospital compared to 0.9% saline. Also, balanced solutions likely reduce the risk of hypokalaemia after intravenous correction. Furthermore, the evidence suggests that balanced solutions compared to 0.9% saline probably produce no changes in the need for additional intravenous fluids or in other biochemical measures such as sodium, chloride, potassium, and creatinine levels. Last, there may be no difference between balanced solutions and 0.9% saline in the incidence of hyponatraemia.

Human Mastadenovirus Infections in Children: A Review of the Current Status in the Arab World in the Middle East and North Africa

Human mastadenovirus (HAdV) is a non-enveloped icosahedral virus with double-stranded DNA genomes. The mortality rate of HAdV infections can reach 35.5%, while gastroenteritis HAdV infections, HAdV pneumonia, and disseminated disease tend to show a worse outcome, with rates ranging from 44.2% to 50%. In addition, HAdV can cause infections at any age but most commonly in the pediatric population, especially in young children and infants. Therefore, this review aims to assess the current status of HAdV infections among children in the Arab World, particularly in the Middle East and North Africa. Web of Science, Scopus, PubMed, EMBASE, and Google Scholar databases for publications in English were searched up to July 2022 for relevant articles. The literature search yielded a total of 21 studies, which were included in this review. Studies reporting HAdV infections in children were conducted in 17 out of the 22 countries. The average prevalence rate of HAdV infections in children was 12.7%, with average prevalence rates of 12.82% and 12.58% in the Middle East and North African countries, respectively. The highest prevalence rate (28.3%) was reported in Egypt, whereas the lowest prevalence (1.5%) was reported in Sudan. The included studies presented children with signs and symptoms of gastroenteritis, acute respiratory infection, acute diarrhea, and acute hemorrhagic conjunctivitis. In conclusion, the average prevalence rate of HAdV infections in children was 12.7%, with average prevalence rates of 12.82% and 12.58% in the Middle East and North African countries, respectively. Finding the precise prevalence rate of this virus is crucial because it will guide future planning for effective disease control and the selection of particular treatment options during epidemics and special seasons.

Clinical, Sociodemographic and Environmental Risk Factors for Acute Bacterial Diarrhea among Adults and Children over Five Years in Bangladesh

In 2016, diarrheal disease was the eighth leading cause of mortality globally accounting for over 1.6 million deaths with the majority of deaths in adults and children over 5 years. This study aims to investigate the clinical, sociodemographic, and environmental risk factors associated with common bacterial acute diarrhea among adults and children over 5. Data were collected from March 2019 to March 2020 in patients over 5 years presenting with acute gastroenteritis at icddr,b. Stool samples were collected from each patient for culture and polymerase chain reaction (PCR) testing. Bivariate associations between independent variables and stool-testing indicating bacterial etiology were calculated. This analysis included 2,133 diarrheal patients of whom a bacterial enteropathogen was identified in 1,537 (72%). Detection of bacteria was associated with: younger age (OR 0.92; 95% CI: 0.88-0.96), lower mean arterial pressure (OR 0.84; 95% CI: 0.79-0.89), heart rate (OR 1.06; 95% CI: 1.01-1.10), percentage dehydration (OR 1.33; 95% CI: 1.13-1.55), respiration rate (OR 1.23; 95% CI: 1.04-1.46), lower mid-upper arm circumference (OR 0.97; 95% CI: 0.94-0.99), confused/lethargic mental status (OR 1.85; 95% CI: 1.11-3.25), rice watery stool (OR 1.92; 95% CI: 1.54-2.41), and vomiting more than three times in the past 24 hours (OR 1.30; 95% CI: 1.06-1.58). Higher monthly income (OR 0.92; 95% CI: 0.86-0.98), > 8 years of education (OR 0.79; 95% CI: 0.63-1.00), and having more than five people living at home (OR 0.80; 95% CI: 0.66-0.98) were associated with lower odds of bacterial diarrhea. These findings may help guide the development of predictive tools to aid in identifying patients with bacterial diarrhea for timely and appropriate use of antibiotics.

Assessment of the incidence and etiology of nosocomial diarrhea in a medical ward in Iraq

This study aimed to detect the incidence, etiology, risk factors, and severity of nosocomial diarrhea among adult inpatients in a medical ward in Iraq. The study was conducted among patients admitted to the medical ward from June 1, 2019, to January 31, 2020, in AL-Sader medical city. The surveillance for nosocomial diarrhea was performed by monitoring every patient in the ward 3 times/week. 1050 patients were admitted to the medical ward in AL-Sader medical city. Of these, 52 patients (mean age 58±12.91 years, range 32 to 80) developed new-onset diarrhea during hospitalization. There was a significant relationship between the severity of diarrhea and age, residence, antibiotic use, including number and duration of antibiotics, immunosuppressive agents (steroids/chemotherapy), duration of hospital stay, level of consciousness, and enema use. Nosocomial diarrhea is a significant clinical problem that complicates about 5% of all admission in the medical ward. Various microorganisms account for nosocomial diarrhea, including E. histolytica, G. lamblia, and Candida. Several risk factors associated with the severe form of nosocomial diarrhea include old age, antibiotic use, immunosuppressive use, and length of hospital stay.

The impact of human vaccines on bacterial antimicrobial resistance. A review

At present, the dramatic rise in antimicrobial resistance (AMR) among important human bacterial pathogens is reaching a state of global crisis threatening a return to the pre-antibiotic era. AMR, already a significant burden on public health and economies, is anticipated to grow even more severe in the coming decades. Several licensed vaccines, targeting both bacterial (Haemophilus influenzae type b, Streptococcus pneumoniae, Salmonella enterica serovar Typhi) and viral (influenza virus, rotavirus) human pathogens, have already proven their anti-AMR benefits by reducing unwarranted antibiotic consumption and antibiotic-resistant bacterial strains and by promoting herd immunity. A number of new investigational vaccines, with a potential to reduce the spread of multidrug-resistant bacterial pathogens, are also in various stages of clinical development. Nevertheless, vaccines as a tool to combat AMR remain underappreciated and unfortunately underutilized. Global mobilization of public health and industry resources is key to maximizing the use of licensed vaccines, and the development of new prophylactic vaccines could have a profound impact on reducing AMR.

Knowledge, Practice of Personal Hygiene, School Sanitation, and Risk Factors of Contracting Diarrhea among Rural Students from Five Western Provinces in China

BACKGROUND

Diarrhea is a global public health issue and a leading cause of childhood malnutrition, growth disturbances, and mortality. The spread of diarrhea is closely linked to the knowledge and maintenance of personal hygiene and quality of drinking water and sanitation facilities. However, there are few such investigations and analysis in rural areas of China. This study aims to determine the association between the risk of contracting diarrhea and knowledge and practices of personal hygiene and school sanitation among rural students as well as provide a scientific basis for preventing the spread of diarrhea and other infectious diseases. A stratified cluster sampling method was used to randomly select 12 rural primary schools in each of 5 counties where the Water, Sanitation and Hygiene (WASH) Plus Program has been implemented. The counties are located in the Guangxi Zhuang autonomous region, Chongqing municipality, Guizhou province, Yunnan province, and Xinjiang Uygur autonomous region. A single fourth-grade class was randomly chosen from each of the 60 schools for observation and a questionnaire survey. The study involved a total of 2330 students. The logistic regression method was adopted to determine the factors contributing to diarrhea in rural students. The results show that male students accounted for 49.40% (n = 1151) of the 2330 research subjects; the average age of the students was 9.9 ± 0.3 years. Approximately 33.09% of the students suffered from diarrhea in the three months leading up to the survey. The odds ratios (ORs) of students who did not know that "diarrhea can be prevented by washing fruits before eating them raw and not drinking untreated water" (OR: 1.303, 95% confidence interval [CI]: 1.063, 1.597) and that "the disease can be prevented by washing hands before meals and after going to the toilet" (OR: 1.522, 95% CI: 1.207, 1.920) were higher than those who knew the above stated facts. Students who "have drunk untreated water at school" (OR: 1.584, 95% CI: 1.268, 1.978), "have drunk untreated water at home" (OR: 1.643, 95% CI: 1.319, 2.048), and "did not wash hands before every meal" (OR: 1.490, 95% CI: 1.120, 1.983) were at a higher risk of contracting diarrhea than those who drank treated water at school and at home and washed their hands before every meal. Diarrhea was more likely to affect students who attended schools with unclean and poorly maintained toilets (OR: 1.586, 95% CI: 1.261, 1.995) or toilets with flies (OR: 1.383, 95% CI: 1.114, 1.717) and without adequate drinking water facilities (OR: 1.407, 95% CI: 1.009, 1.962). The knowledge of methods to maintain personal hygiene, general hygiene practices, and school sanitation are the three major risk factors that account for the spread of diarrhea among rural students from five western provinces (municipalities and autonomous regions) of China. Therefore, to prevent such diseases and maintain health, it is important to provide students with health education, help them develop good hygiene habits, ensure the provision of clean water at schools, and improve the overall school environments.

Intestinal protozoa in hospitalized under-five children with diarrhoea in Nampula - a cross-sectional analysis in a low-income setting in northern Mozambique

Background

In Mozambique, infection by intestinal parasites is reported all over the country. However, infection in children with diarrhoea is mostly focused in the southern region of Mozambique. This work aims to determine the frequency and potential risk factors for infection by Cryptosporidium spp., Giardia lamblia, and Entamoeba histolytica in children under-five years hospitalized with diarrhoea in Hospital Central de Nampula, northern Mozambique.

Methods

A cross-sectional hospital-based surveillance was conducted between March 2015 and January 2018 in children admitted with diarrhoea in Hospital Central de Nampula. Sociodemographic information was obtained through semi-structured interviews applied to the children’s caregivers. A single stool sample was collected from each child to detect antigens from Cryptosporidium spp., G. lamblia, and E. histolytica using an immune-enzymatic technique. Crude and adjusted odds ratios (with 95% Confidence Intervals) were obtained by logistic regression models to identify factors associated with infection by Cryptosporidium spp. and G. lamblia.

Results

The median age and interquartile intervals of our sample population was 12 months (8–20). Intestinal protozoa were detected in 21.4% (59/276). Cryptosporidium spp. was the most common protozoa (13.9% - 38/274), followed by G. lamblia (9.1% - 25/274) and E. histolytica (0.4% - 1/275). Children with illiterate caregiver’s (p-value = 0.042) and undernourished (p-value = 0.011) were more likely to be infected by Cryptosporidium spp. G. lamblia was more common in children living in households with more than four members (p-value = 0.039). E. histolytica was detected in an eleven month’s child, co-infected with Cryptosporidium spp. and undernourished.

Conclusion

Cryptosporidium spp. and Giardia lamblia were the most common pathogenic intestinal protozoa detected in children with diarrhoea hospitalized in the Hospital Central de Nampula. Our findings obtained highlight the importance of exploring the caregiver’s education level, children’s nutritional status for infections with Cryptosporidium spp., and living conditions, namely crowded households for infections with G. lamblia in children younger than five years.

Is There a Role for Bismuth in Diarrhea Management?

Diarrhea, an illness of both the developed and developing world, involves the burdensome characteristics of frequent bowel movements, loose stools, and abdominal discomfort. Diarrhea is a long-standing challenge in palliative care and can have a myriad of causes, making symptomatic treatment pertinent when illness evaluation is ongoing, when there is no definitive treatment approach, or when effective treatment cannot be attained. Symptomatic therapy is a common approach in palliative care settings. Bismuth is a suitable agent for symptomatic therapy and can be effectively employed for management of chronic diarrhea. The objective of this narrative review is to examine the role of bismuth in management of diarrheal symptoms. To explore this, PubMed (including Medline) and Embase were used to search the existing literature on bismuth and diarrhea published from 1980 to 2019. It was found that bismuth has potential utility for diarrheal relief in multiple settings, including microscopic colitis, traveler's diarrhea, gastrointestinal infection, cancer, and chemotherapy. It also has great potential for use in palliative care patients, due to its minimal side effects. Overall, the antisecretory, anti-inflammatory, and antibacterial properties of bismuth make it a suitable therapy for symptomatic treatment of diarrhea. The limited range of adverse side effects makes it an appealing option for patients with numerous comorbidities. Healthcare providers can explore bismuth as an adjunct therapy for diarrhea management in an array of conditions, especially in the palliative care setting.

Outcomes and clinical relevance of stool multiplex bacterial polymerase chain reaction in patients with acute diarrhea: single center experience

BACKGROUND/AIMS

Diagnostic stool multiplex polymerase chain reaction (PCR) testing has attracted considerable interest, because of its high sensitivity, short turnaround time, and ability to detect multiple organisms simultaneously. This study investigates the clinical usefulness of a stool multiplex bacterial PCR in patients with acute diarrhea.

METHODS

We retrospectively evaluated the stool multiplex bacterial PCR results, clinical parameters, and clinical courses of patients hospitalized because of acute diarrhea between August 2014 and November 2016.

RESULTS

A total of 725 patients (male, 372; mean age, 30.9 ± 29.3 years) underwent stool multiplex bacterial PCR. A total of 243 pathogens were detected in 226 patients. The detection rate of multiplex PCR testing was higher than that of stool culture (32.7% vs. 3.3%, p < 0.01). Severe symptoms of acute diarrhea (bloody diarrhea, frequent diarrhea) and prescribed empirical antibiotics were significantly more common in the positive multiplex PCR group (p = 0.02, p < 0.01, p < 0.01, respectively). However, mean durations of hospital stay were similar in the 2 groups according to the multiplex PCR results (p = 0.32). In addition, Campylobacter spp., which was the most commonly detected pathogen (97/243, 39.9%), was significantly associated with frequent diarrhea and prescribed empirical antibiotics (p < 0.01), but not with duration of hospital stay (p = 0.09).

CONCLUSION

We concluded that stool multiplex bacterial PCR might be a useful tool for identifying bacterial etiology in patients with acute diarrhea, especially in those with Campylobacter spp. infection.

Gelatin tannate for acute diarrhoea and gastroenteritis in children: a systematic review and meta-analysis

OBJECTIVE

To determine the effectiveness and safety of gelatin tannate (GT) for reducing the duration of the acute diarrhoea and gastroenteritis (ADG) in children.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE, Embase, CINAHL, Cochrane Central Register of Controlled Trials, LILACS and grey literature, published from inception to October 2018. No language restrictions.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials in children with ADG, comparing GT with placebo.

RESULTS

Of 797 titles identified, we included three studies (276 children). We performed a random effects model meta-analysis for the main outcome (diarrhoea duration). We did not find significant differences between GT and placebo for diarrhoea duration (mean difference (MD)=-15.85 hours; 95% CI -42.24 to 14.82, I2=92%; three studies), stool frequency at day 2 (MD=0.11 stools/day; 95% CI -0.39 to 0.62: I2=26%; two studies), diarrhoea at day 3 (risk ratio [RR]=0.46; 95% CI 0.06 to 3.47: I2=73%; two studies), vomiting (RR=1.31; 95% CI 0.95 to 1.80: I2=0%; two studies) or adverse events (RR=0.86; 95% CI 0.27 to 2.66: I2=0%; two studies). Most common adverse events included abdominal pain and nausea.

CONCLUSION

The effect of GT was no different to placebo for mean diarrhoea duration (low certainty on the evidence) and stool frequency at day 2 (high certainty) and for the presence of diarrhoea at day 3 (very low certainty) of vomiting (moderate certainty) and of adverse events (low certainty).

PROSPERO REGISTRATION NUMBER

CRD42018087902.

Acute Infectious Diarrhea and Gastroenteritis in Children

PURPOSE OF REVIEW

We aimed to summarize the most current evidence on the main aspects of the diarrheal diseases in children. The following key elements were addressed: definitions, etiology, pathogenesis, diagnosis, dietary management, pharmacological treatments, and prevention. We covered the following questions: What are the most important clinical and laboratory features of the disease? What are the best approaches for the dietary management? What is the best way to classify the hydration status, and to prevent and treat the dehydration? What are the most effective and safe interventions for reducing the diarrhea and vomiting?

RECENT FINDINGS

Diarrheal diseases are one of the most common diseases in childhood. The most common cause is rotavirus. A key element in the approach of a child with diarrhea is determining their hydration status, which determines the fluid management. Laboratory tests are nor routinely required, as most of the cases, they do not affect the management and it should be indicated only in selected cases. Several treatments have been studied to reduce the duration of the diarrhea. Only symbiotics and zinc have shown to be effective and safe with high certainty on the evidence. Rest of the interventions although seem to be effective have low to very low quality of the evidence. The only effective and safe antiemetic for controlling vomiting is ondansetron. A list of antimicrobials indications according to the identified microorganisms is provided. We summarized the most current evidence on diagnosis, management, and prevention of diarrhea in children. More research is needed in some areas such as dehydration scales, rehydration management, antidiarrheals, and antibiotic treatments.

Etiologic agents of acute diarrhea in sentinel surveillance sites in Vientiane Capital, Lao People's Democratic Republic, 2012-2015

This study aims to identify the pathogens of diarrhea in Vientiane Capital, Lao People's Democratic Republic (Lao PDR). The data of 2482 patients who visited eight health facilities due to diarrhea in 2012-2015 were retrospectively reviewed. Stool or rectal swabs collected from all patients were tested for bacteria. Children who were under 5 years old were additionally tested for rotavirus. Of 2482 cases, 1566 cases were under 5 years old, and at least one enteropathogen was detected in 475 cases (19.1%). Salmonella species was the most commonly detected bacterial pathogen. Enteropathogenic Escherichia coli (EPEC) and Salmonella species was the major pathogen in the dry season and the wet season, respectively. Eighty-seven patients tested positive for multiple bacteria. Rotavirus was detected in 291 children under 5 years old (32.4%), mostly from October to April. The major bacteria of coinfection with rotavirus were EPEC followed by Salmonella species. Salmonella species was the predominant bacterial pathogen of diarrhea of all ages, and rotavirus was the predominant pathogen among children under 5 years old. Further studies examining other types of pathogens for diarrhea and the introduction of a rotavirus vaccine for children are needed in Lao PDR.

Burden of Shigella spp and Vibrio spp, and their antibiotic sensitivity pattern in the patients with acute gastroenteritis in tertiary care hospital in Nepal

Objectives

The present study aims to investigate the etiology, clinical profile and resistance pattern of the isolated pathogens in Nepalese adults with acute gastroenteritis. This cross-sectional study was conducted at Sukraraj Tropical and Infectious Disease Hospital, from April 2016 to Sep 2017. Subjects’ ages 14 or above, presenting with gastroenteritis with positive stool culture were enrolled for analysis.

Results

Of total 153 patients, 47.72% subjects confirmed the presence of bacterial infection. Vibrio cholerae spp and Shigella spp were detected in 36.6% and 23.28% respectively. The most common resistance among Vibrio cholerae was to nitrofurantoin (92.8%), cotrimoxazole (92.8%) and nalidixic acid (92.8%). Among 17 isolates of Shigella spp, the most frequent drug resistant was observed in ampicillin (64.7%), nalidixic acid (58.8%), ceftriaxone (47%). Chloramphenicol (94.1%), tetracycline (88.2%), and cotrimoxazole (82.3%) were found to be the most sensitive towards this pathogen. High rate of diarrhea due to bacterial infection, especially Shigella spp and Vibrio spp and their high rate of drug resistance emphasize an urgent need of designing a surveillance system for antimicrobial resistance in Nepalese setting.

Multiplex PCR assay for simultaneous detection and differentiation of Entamoeba histolytica, Giardia lamblia, and Salmonella spp. in the municipality-supplied drinking water

BACKGROUND

The contamination with Entamoeba histolytica, Giardia lamblia, and Salmonella spp. in drinking water is the most prevalent in Indian subcontinent, but often difficult to detect all these pathogens from the drinking water.

MATERIALS AND METHODS

A multiplex polymerase chain reaction (mPCR) method was developed to detect contamination of municipality-supplied drinking water with E. histolytica, G. lamblia, and Salmonella spp. The primers were designed to target small subunit of 16S rRNA type gene of E. histolytica and G. lamblia, and invasive A gene of Salmonella typhimurium. The optimized mPCR assay was applied on 158 municipality-supplied drinking water samples collected from Delhi.

RESULTS

Out of total 158 water samples, 89 (56.32%) were found positive for the targeted pathogens by mPCR while conventional methods could be detected only in 11 (6.96%) samples. The mPCR assay showed 100% sensitivity and specificity for these pathogens in comparison with culture and microscopic detection. Of the 89 mPCR-positive samples, G. lamblia, E. histolytica, and Salmonella spp. were present in 35 (22.15%), 26 (16.45%), and 28 (17.72%), respectively. Nine (5.69%) samples were positive for both E. histolytica and G. lamblia, 10 (6.32%) were positive for G. lamblia and Salmonella spp., and 8 (5.06%) had Salmonella spp. and E. histolytica. Nonetheless, 3 (1.89%) samples were positive for all three pathogens.

CONCLUSIONS

The present assay is an alternative to conventional methods to serve as highly sensitive, specific, and economical means for water quality surveillance to detect the outbreak caused by E. histolytica, G. lamblia, and Salmonella spp. pathogens.

Virulent Escherichia coli strains among Egyptian patients with acute diarrhoea versus urinary tract infection, and their antibiotic susceptibility

BACKGROUND AND STUDY AIMS

Diarrhoea and urinary tract infection (UTI) are common clinical problems. Meanwhile, Escherichia coli (E. coli), is the commonest bacterial pathogen reported in both of them. This study aimed to evaluate the pathogenic E. coli (PEC) in stool of acute diarrhoea and urine of UTI regarding their virulence genes and their influence on the susceptibility to routinely prescribed antibiotics.

PATIENTS AND METHODS

Twenty two stool and another 22 urine samples of patients with acute diarrhoea and UTI respectively were collected from patients admitted at Kasr Al-Ainy Hospital, Faculty of Medicine, Cairo University, Egypt. E. coli isolation, identification of their phyla; chuA, yjaA, and TspE4.C2, and further identification of 10 virulent genes; fimH, papC, papG//, papG///, papEF, afa, sfa, CNF1, iroN & hlyA was performed. Antibiotic susceptibility was studied against quinolones, gentamicin (GM), and trimethoprim-sulphamethoxazole (TMP-SMX).

RESULTS

The studied virulence genes were comparably detected in both pathogenic samples. In diarrheogenic E. coli (DEC); phylum A was significantly related to both ciprofloxacin (CIP) and TMP-SMX resistance, and both of the virulence genes fimH and iroN were significantly related to all the studied antibiotics resistance, while afa was significantly related to nalidixic acid (NA) resistance. In uropathogenic E. coli (UEC); phylum D was significantly related to CIP and levofloxacin resistance, and both of the virulence genes fimH and iroN were significantly related to most of the studied antibiotics resistance.

CONCLUSION

The isolated PEC was evidently and broadly resistant to the studied antibiotics, with limited influence of their phyla and virulence genes (fimH and iroN).

Multiplex PCR reveals a high prevalence of multiple pathogens in traveller's diarrhoea in children

OBJECTIVE

Traveller's diarrhoea (TD) is one of the most frequent illnesses affecting children returning from tropical countries. The purpose of this study was to assess the distribution of pathogens associated with TD in children using a multiplex PCR assay on stool samples.

DESIGN

All the children admitted for TD in two university hospitals from 1 August to 15October during 2014 and 2015 were included in a prospective study. Stool samples were tested by a multiplex PCR FilmArray GI panel detecting 22 pathogens. Performances for the detection of major enteropathogenic bacteria (Salmonella, Shigella and Campylobacter spp) by multiplex PCR and conventional culture methods were compared. The prevalence of extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae was also determined.

RESULTS

Fifty-nine children were included. In 58 cases (98%), at least one pathogen was identified, including 9 different enteropathogenic bacteria, 5 viruses and 2 parasites. Multiplex PCR enhanced the enteropathogenic bacteria detection by 25%. The most frequent pathogens were enteroaggregative Escherichia coli (n=32), enteropathogenic E. coli (n=26), enterotoxigenic E. coli (n=19), Salmonella enterica, enteroinvasive E. coli/Shigella (n=16 each), Cryptosporidium, sapovirus (n=11 each), Campylobacter jejuni, norovirus (n=10 each), rotavirus (n=9), Giardia (n=8) and Shiga-toxin-producing E. coli (n=4). Fifty-two coinfections were observed, notably including bacteria and viruses (n=21), multiple bacteria (n=14), or bacteria and parasites (n=10). ESBL were detected in 28 cases. Multiplex PCR could optimise the number of treated patients by 27% compared with stool cultures.

CONCLUSION

Multiplex PCR on stools revealed a high prevalence of diverse enteric pathogens and coinfections in children with TD. Major enteropathogenic bacteria were more frequently detected by multiplex PCR compared with conventional culture. Finally, this technique allows the start of appropriate and early antibiotic treatment and seems to optimise the number of correctly treated patients.

Comparative effectiveness and safety of interventions for acute diarrhea and gastroenteritis in children: A systematic review and network meta-analysis

BACKGROUND

Many interventions have shown effectiveness in reducing the duration of acute diarrhea and gastroenteritis (ADG) in children. Yet, there is lack of comparative efficacy of interventions that seem to be better than placebo among which, the clinicians must choose. Our aim was to determine the comparative effectiveness and safety of the pharmacological and nutritional interventions for reducing the duration of ADG in children.

METHODS

Data sources included Medline, Embase, CENTRAL, CINAHL, LILACS, and Global-Health up to May 2017. Eligible trials compared zinc (ZN), vitamin A, micronutrients (MN), probiotics, prebiotics, symbiotics, racecadotril, smectite(SM), loperamide, diluted milk, lactose-free formula(LCF), or their combinations, to placebo or standard treatment (STND), or among them. Two reviewers independently performed screening, review, study selection and extraction. The primary outcome was diarrhea duration. Secondary outcomes were stool frequency at day 2, diarrhea at day 3, vomiting and side effects. We performed a random effects Bayesian network meta-analysis to combine the direct and indirect evidence for each outcome. Mean differences and odds ratio with their credible intervals(CrI) were calculated. Coherence and transitivity assumptions were assessed. Meta-regression, subgroups and sensitivity analyses were conducted to explore the impact of effect modifiers. Summary under the cumulative curve (SUCRA) values with their CrI were calculated. We assessed the evidence quality and classified the best interventions using the Grading of Recommendations, Assessment, Development & Evaluation (GRADE) approach for each paired comparison.

RESULTS

A total of 174 studies (32,430 children) proved eligible. Studies were conducted in 42 countries of which most were low-and middle-income countries (LMIC). Interventions were grouped in 27 categories. Most interventions were better than STND. Reduction of diarrhea varied from 12.5 to 51.1 hours. The combinations Saccharomyces boulardii (SB)+ZN, and SM+ZN were considered the best interventions (i.e., GRADE quality of evidence: moderate to high, substantial superiority to STND, reduction in duration of 35 to 40 hours, and large SUCRA values), while symbiotics (combination of probiotics+prebiotics), ZN, loperamide and combinations ZN+MN and ZN+LCF were considered inferior to the best and better than STND [Quality: moderate to high, superior to STND, and reduction of 17 to 25 hours]. In subgroups analyses, effect of ZN was higher in LMIC and was not present in high-income countries (HIC). Vitamin A, MN, prebiotics, kaolin-pectin, and diluted milk were similar to STND [Quality: moderate to high]. The remainder of the interventions had low to very-low evidence quality. Loperamide was the only intervention with more side effects than STND [Quality: moderate].

DISCUSSION/CONCLUSION

Most interventions analyzed (except vitamin A, micronutrients, prebiotics, and kaolin-pectin) showed evidence of superiority to placebo in reducing the diarrhea. With moderate-to high-quality of evidence, SB+ZN and SM+ZN, demonstrated the best combination of evidence quality and magnitude of effect while symbiotics, loperamide and zinc proved being the best single interventions, and loperamide was the most unsafe. Nonetheless, the effect of zinc, SB+ZN and SM+ZN might only be applied to children in LMIC. Results suggest no further role for studies comparing interventions against no treatment or placebo, or studies testing loperamide, MN, kaolin-pectin, vitamin A, prebiotics and diluted milk.

PROSPERO REGISTRATION

CRD42015023778.

Observe Before You Leap: Why Observation Provides Critical Insights for Formative Research and Intervention Design That You'll Never Get From Focus Groups, Interviews, or KAP Surveys

Four case studies show how observation can uncover issues critical to making a health intervention succeed or, sometimes, reveal reasons why it is likely to fail. Observation can be particularly valuable for interventions that depend on mechanical or clinical skills; service delivery processes; effects of the built environment; and habitual tasks that practitioners find difficult to articulate.

Formative research is essential to designing both study instruments and interventions in global health. While formative research may employ many qualitative methods, focus group discussions and in-depth interviews are the most common. Observation is less common but can generate insights unlikely to emerge from any other method. This article presents 4 case studies in which observation revealed critical insights: corralling domestic poultry to reduce childhood diarrhea, promoting insecticide-treated bed nets (ITNs) to prevent malaria, evaluating skilled birth attendant competency to manage life-threatening obstetric and neonatal complications, and assessing community health worker (CHW) ability to use malaria rapid diagnostic tests (RDTs). Observation of Zambian CHWs to design malaria RDT training materials revealed a need for training on how to take finger-stick blood samples, a procedure second nature to many health workers but one that few CHWs had ever performed. In Lima, Peru, study participants reported keeping their birds corralled “all the time,” but observers frequently found them loose, a difference potentially explained by an alternative interpretation of the phrase “all the time” to mean “all the time (except at some specific seemingly obvious times).” In the Peruvian Amazon, observation revealed a potential limitation of bed net efficacy due to the built environment: In houses constructed on stilts, many people sleep directly on the floor, allowing mosquitoes to bite from below through gaps in the floorboards. Observation forms and checklists from each case study are included as supplemental files; these may serve as models for designing new observation guides. The case studies illustrate the value of observation to clearly understanding clinical practices and skills, details about how people carry out certain tasks, routine behaviors people would most likely not think to describe in an interview, and environmental barriers that must be overcome if an intervention is to succeed. Observation provides a way to triangulate for social desirability bias and to measure details that interview or focus group participants are unlikely to recognize, remember, or be able to describe with precision.

Livestock ownership is associated with higher odds of anaemia among preschool-aged children, but not women of reproductive age in Ghana

Livestock ownership may influence anaemia through complex and possibly contradictory mechanisms. In this study, we aimed to determine the association of household livestock ownership with anaemia among women aged 15–49 years and children aged 6–59 months in Ghana and to examine the contribution of animal source foods (ASFs) to consumption patterns as a potential mechanism mediating this association. We analysed data on 4,441 women and 2,735 children from the 2014 Ghana Demographic and Health Survey and 16,772 households from the Ghana Living Standards Survey Round 6. Haemoglobin measurements were used to define anaemia (non‐pregnant women: <120 g/L; children: <110 g/L). Child‐ and household‐level ASF consumption data were collected from 24‐hour food group intake and food consumption and expenditure surveys, respectively. In multiple logistic regression models, household livestock ownership was associated with anaemia among children (OR, 95% CI: 1.5 [1.1, 2.0]), but not women (1.0 [0.83, 1.2]). Household ownership of chickens was associated with higher odds of anaemia among children (1.6 [1.2, 2.2]), but ownership of other animal species was not associated with anaemia among women or children. In path analyses, we observed no evidence of mediation of the association of household livestock ownership with child anaemia by ASF consumption. Ownership of livestock likely has limited importance for consumption of ASFs among young children in Ghana and may in fact place children at an increased risk of anaemia. Further research is needed to elucidate if and how pathogen exposure associated with livestock rearing may underlie this increased risk of anaemia.

Fecal microbiota transplantation for recurrent clostridium difficile infection in children

Fecal microbiota transplantation (FMT) is a relatively simple, promising treatment for recurrent Clostridium difficile infection. While there are a wide variety of approaches including mode of delivery, the results are nonetheless encouraging, even amongst younger children. Experience with FMT in the pediatric population is increasing, showing similar success compared to adults. This article will provide an overview of C. difficile infection along with review of the rationale, methods and complications of FMT including the current experience of FMT in children.

Enterovirus detection in patients with acute gastroenteritis in Switzerland

Acute gastroenteritis (GE) has a major impact on morbidity and mortality worldwide, yet comprehensive data regarding infectious agents including enteroviruses are scarce. We hypothesized that enteroviruses constitute a significant cause of acute GE. We analyzed 677 stool samples from 504 patients, which had been submitted for suspected infectious GE. 0.2 mL of stool suspension was extracted using the Abbott m2000_sp robot and analysed by multiplex nucleic acid testing (NAT) using the Luminex xTAG gastrointestinal pathogen panel (GPP) as well as by specific NATs detecting enteroviruses and polioviruses. Median age of the patients was 6.6 years (IQR 1.1-50.6; pediatric <18 years). 292 of 677 (43%) samples were positive for at least one pathogen. Enterovirus was detected in 5.3% (36/677) as sole pathogen (67%), and more frequently in children (P = 0.0054). Only rotavirus (18.6%) and norovirus (12.1%) were more frequent. Clostridium difficile and Campylobacter jejuni were detected in 5.5% and 2.2% of stools, respectively. Adenovirus, E. coli O157, Salmonella, Shiga toxin-producing E. coli (STEC), Shigella, Giardia lamblia, Cryptosporidium, and Entamoeba histolytica were rare (<1% of samples). Vibrio cholerae, Yersinia enterocolitica, enterotoxigenic E. coli (ETEC) and poliovirus were not detected. Thus, non-polio enteroviruses are the third most frequent pathogen in acute GE suggesting that enteroviruses may play an important role in GE even in developed, industrial health care settings.

Prevalence of enteric infections among hospitalized patients in two referral hospitals in Ghana

Background

Diarrhea is an important cause of morbidity and mortality worldwide. In Africa and Ghana in particular, it is estimated to contribute directly to 19 and 25% of pediatric mortality among children under 5 years, respectively.

Methods

Surveillance for hospitalized acute diarrheal illness was initiated in November 2010 through October 2012 in a referral hospital in southern Ghana, and a teaching hospital in northern Ghana. Consenting hospitalized patients who met a standardized case definition for acute diarrheal illness provided demographic and epidemiologic data. Stool samples were collected and tested by culture for bacteria and by enzyme immunoassays for a panel of viruses and parasites.

Results

A total of 429 patients were enrolled; 216 (50.3%) were under 5 years, and 221 (51.5%) were females. Stool samples were received from 153 patients. Culture isolates included Shigella sp., Salmonella spp., Plesiomonas sp. and Vibrio cholerae. Of 147 samples tested for viruses, 41 (27.9%) were positive for rotaviruses, 11 (7.5%) for astroviruses, 10 (6.8%) for noroviruses, and 8 (5.4%) for adenoviruses. Of 116 samples tested for parasitic infections; 4 (3.4%) were positive for Cryptosporidium sp. and 3 (2.6%) for Giardia lamblia. Of the enrolled patients, 78.8% had taken antibiotics prior to sample collection.

Conclusions

Diarrheal pathogens were identified across all ages, however, predominantly (81%) in the children under 5 years of age. This study also detected high antibiotic use which has the potential of increasing antibiotic resistance. The most common enteric pathogen detected (49.4%) was rotavirus.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-017-2621-x) contains supplementary material, which is available to authorized users.

Isolation and evaluation of Candida species and their association with CD4+ T cells counts in HIV patients with diarrhoea

BACKGROUND

Gastrointestinal infection is one of the most common infections among HIV patients. Candida spp have been implicated in the aetiology of chronic diarrhoea in HIV patients, but little is known about this in Nigeria.

OBJECTIVES

We determined the prevalence of faecal candidiasis in HIV patients in relation to diarrhoea, CD4 counts, and other socio-demographic factors and the spectrum of Candida isolates involved.

METHODS

One hundred and fifty four HIV patients were investigated. Candida species were identified by standard techniques. Socio-demographic and clinical information was obtained from the patients using a structured questionnaire. The CD4 count was estimated using a single platform flow cytometer.

RESULTS

Candida overgrowth was detected in 61 (39.5%) HIV patients, and diarrhoea was associated with candidiasis in the subjects (P=0.001). Candidiasis was commonly detected among subjects in the 29-39 years' age group. A CD4 count below 200 cells/mm² (62.3%) was a risk factor for acquiring candidiasis among HIV patients (P=0.001). Candida albicans (65.6%) was the most frequently recovered species followed by Candida krusei (16.4%) and Candida tropicalis (14.8%).

CONCLUSION

Candidiasis is an important opportunistic infection in HIV-patients in Ile-Ife. There is need for regular checks for opportunistic infections, including candidiasis in HIV patients to monitor disease progression and prevent subsequent complications.

Cryptosporidiosis in children in the Indian subcontinent

Cryptosporidiosis is a leading cause of diarrheal disease among children under two in developing countries. Previous estimates have shown a high burden of cryptosporidial diarrhea in children from Sub-Saharan Africa and South Asia. Asymptomatic cryptosporidial infections which go undetected and untreated have been shown to result in significant malnutrition. In this review, we carried out a literature search of studies published on cryptosporidiosis in children in the Indian subcontinent from 1983 to 2016. Of the 154 publications identified, 54 were included for final analysis with both hospital-based and community-based studies. There were wide variations in reported prevalence rates from hospital studies and highlight the need to be carry out these studies with uniform sampling and molecular tools for detection, especially in countries with a dearth of information. Community-based studies, however, showed similarities in spite of differences in when (the late 1990s up until recently) and where (South India or Bangladesh) they were conducted. When more sensitive detection methods were used, cryptosporidial diarrhea accounted for 7%–9% of all diarrhea episodes and 20%–30% of children in these cohorts experienced at least one cryptosporidial diarrheal episode. High rates of asymptomatic infections with increased detection by serology and multiple infections (symptomatic and asymptomatic) were also documented in all cohorts. This overview brings to light the high burden of disease associated with cryptosporidiosis in children in the subcontinent and the gaps in knowledge to be addressed.

Identification of different Escherichia coli pathotypes in north and north-west provinces of Iran

BACKGROUND AND OBJECTIVES

Diarrhea is one of the most prevalent diseases in the world, specially in developing countries. One of the most important causative agents of bacterial diarrhea is diarrheagenic Escherichia coli (DEC) which causes gastroenteritis and this group involving enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), enteroaggregative E. coli (EAEC), enterohemoragic E. coli (EHEC), enteroinvasive E. coli (EIEC), diffusely adherence E. coli (DAEC). The aim of this study was to identify different E. coli pathotypes in north and north-west of Iran, among the clinical isolates.

MATERIALS AND METHODS

In this study for identification of E. coli, 170 fecal samples were cultured on MacConkey agar and identified by biochemical tests. Samples with E. coli characteristics were selected (145 samples) and their genomes were purified by phenol-chloroform method. After extraction of genomes, lt and sta genes identified by PCR for ETEC, eae gene for atypical and eae and bfp for typical EPEC, AA region for EAEC, stx₁ and stx₂ and eae genes for EHEC (stx₁ or stx₂ or both for STEC) and invE for EIEC.

RESULTS

Finally 10 samples identified as ETEC (%5.88), 18 (%10.58) EPEC, 6 (%3.52) EHEC and 12 (7.05%) samples were STEC. None of the samples were positive for EAEC and EIEC.

CONCLUSION

The results obtained in this study showed that ETEC, EPEC, EHEC and STEC are prevalent bacterial agents in north and north-west of Iran. Complementary studies to identify these pathotypes in other seasons can help to adopt necessary policies against outbreaks in Iran.

A novel P/Ag/Ag2O/Ag3PO4/TiO2 composite film for water purification and antibacterial application under solar light irradiation

TiO₂-based thin films have been intensively studied in recent years to develop efficient photocatalyst films to degrade refractory organics and inactivate bacteria for wastewater treatment. In the present work, P/Ag/Ag₂O/Ag₃PO₄/TiO₂ composite films on the inner-surface of glass tube were successfully prepared via sol-gel approach. P/Ag/Ag₂O/Ag₃PO₄/TiO₂ composite films with 3 coating layers, synthesized at 400°C for 2h, showed the optimal photocatalytic performance for rhodamine B (Rh B) degradation. The results indicated that degradation ratio of Rh B by P/Ag/Ag₂O/Ag₃PO₄/TiO₂ composite film reached 99.9% after 60min under simulated solar light, while just 67.9% of Rh B was degraded by pure TiO₂ film. Moreover, repeatability experiments indicated that even after five recycling runs, the photodegradation ratio of Rh B over composite film maintained at 99.9%, demonstrating its high stability. Photocatalytic inactivation of E. coli with initial concentration of 10⁷CFU/mL also showed around 100% of sterilization ratio under simulated solar light irradiation in 5min by the composite film. The radical trapping experiments implied that the major active species of P/Ag/Ag₂O/Ag₃PO₄/TiO₂ composite films were photo-generated holes and O₂^- radicals. The proposed photocatalytic mechanism shows that the transfer of photo-induced electrons and holes may reduce the recombination efficiency of electron-hole pairs and potential photodecomposition of composite film, resulting in enhanced photocatalytic ability of P/Ag/Ag₂O/Ag₃PO₄/TiO₂ composite films.

Protein Malnutrition Impairs Intestinal Epithelial Cell Turnover, a Potential Mechanism of Increased Cryptosporidiosis in a Murine Model

Malnutrition and cryptosporidiosis form a vicious cycle and lead to acute and long-term growth impairment in children from developing countries. Insights into mechanisms underlying the vicious cycle will help to design rational therapies to mitigate this infection. We tested the effect of short-term protein malnutrition on Cryptosporidium parvum infection in a murine model by examining stool shedding, tissue burden, and histologic change and explored the mechanism underlying the interaction between malnutrition and cryptosporidiosis through immunostaining and immunoblotting. Protein malnutrition increased stool shedding and the number of intestine-associated C. parvum organisms, accompanied by significant suppression of C. parvum-induced caspase 3 activity and expression of PCNA and Ki67, but activation of the Akt survival pathway in intestinal epithelial cells. We find that even very brief periods of protein malnutrition may enhance (or intensify) cryptosporidiosis by suppressing C. parvum-induced cell turnover and caspase-dependent apoptosis of intestinal epithelial cells. This implicates a potential strategy to attenuate C. parvum's effects by modulating apoptosis and promoting regeneration in the intestinal epithelium.

Rapid Molecular Approach for Simultaneous Detection of Salmonella spp., Shigella spp., and Vibrio cholera

OBJECTIVES

Gastrointestinal tract infection is still one of the serious public health problems in many geographic areas and is endemic in most countries including Iran. Early detection of the gastrointestinal tract pathogens can be extremely important. The aim of the current study was to apply a shortened time-multiplex polymerase chain reaction (PCR) for rapid and simultaneous detection of Salmonella spp., Shigella spp., and Vibrio cholera.

METHODS

The standard and clinical strains of Salmonella spp., Shigella spp., and V. cholerae were used in the assay. Multiplex PCR was performed and optimized based on amplification of invA, putative integrase, and ompW genes for detecting Salmonella spp., Shigella spp., and V. cholerae, respectively. The specificity of the assay was evaluated by testing 12 different bacterial species.

RESULTS

Only Salmonella spp., Shigella spp., and V. cholerae strains had positive results when subjected to the assay using multiplex PCR. The assay showed a high sensitivity, and no amplification products were observed in multiplex PCR with any of the other microorganisms.

CONCLUSION

Our study indicated that the invA, putative integrase, and ompW-based multiplex PCR assay appears to be an efficient method for rapid and simultaneous detection of Salmonella spp., Shigella spp., and V. cholerae.

Time series investigation of changes in seasonality of acute diarrhea hospitalizations before and after rotavirus vaccine in Southern Brazil

Diarrhea by rotavirus is one of the main causes of mortality in children in developing countries, although the hospitalization rates (HR) for acute diarrhea have been found to have fallen since the introduction of the rotavirus vaccine. However, the patterns of the rotavirus are still not well understood and seasonal peaks occur throughout the year, with variations between countries and over time. The main objective of this study was to analyze the temporal behavior of HR caused by acute diarrhea in children under the age of one in the south of Brazil, between 2000 and 2011, and to explore changes in seasonality patters after the introduction of the vaccine against the rotavirus in 2006. Harmonic and multiscale wavelet analyses were used to detect seasonality and the points of change in the temporal scale. The statistical significance of each seasonality that was identified was tested using Fisher's test. The harmonic and wavelet analyses show annual seasonal and six-monthly patterns for HR, as well as a clear change after the introduction of the vaccine in 2006.

Molecular testing for clinical diagnosis and epidemiological investigations of intestinal parasitic infections

Over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. DNA samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. A variety of technologies have been applied, and some specific and general pitfalls and limitations have been identified. This review provides an overview of the multitude of methods that have been reported for the detection of intestinal parasites and offers some guidance in applying these methods in the clinical laboratory and in epidemiological studies.

HIGH PREVALENCE OF Blastocystis spp. INFECTION IN CHILDREN AND STAFF MEMBERS ATTENDING PUBLIC URBAN SCHOOLS IN SÃO PAULO STATE, BRAZIL

After a gastroenteritis outbreak of unknown etiology in the municipality of Sebastião da Grama, SãoPaulo, Brazil, we conducted a parasitological survey to establish the epidemiological profile of enteroparasitosis in children and staff members attending the public urban schools in operation in town. The cross-sectional study evaluated 172 children aged 11 months to 6 years old and 33 staff members aged 19 to 58 years old. Overall, 96 (55.81%) children and 20 (60.61%) staff members were mono-parasitized, while 58 (33.72%) children and 4 (12.12%) workers were poly-parasitized. Protozoa (88.37%; 72.73%) was more prevalent than helminthes (3.48%; 0%) in children and staff members respectively.Blastocystis spp. was the most prevalent parasite in children (86.63%) and staff members (66.67%). The age of 1 year old or less was found to be associated with increased prevalence of giardiasis [OR = 13.04; 95%CI 2.89-58.91; p = 0.00] and public garbage collection was identified as a protective factor against intestinal helminth infections [OR = 0.06; 95%CI 0.00-0.79; p = 0.03]. Although most of the children tested positive for Blastocystis spp. and also presented clinical signs/symptoms (62.2%), this association was not statistically significant [OR = 1.35; 95%CI 0.53-3.44; p = 0.51]. Intestinal parasites still represent a public health concern and this study underscores the importance of further investigations to better understand the pathogenic role of Blastocystis spp.

Planning for climate change: The need for mechanistic systems-based approaches to study climate change impacts on diarrheal diseases

Increased precipitation and temperature variability as well as extreme events related to climate change are predicted to affect the availability and quality of water globally. Already heavily burdened with diarrheal diseases due to poor access to water, sanitation and hygiene facilities, communities throughout the developing world lack the adaptive capacity to sufficiently respond to the additional adversity caused by climate change. Studies suggest that diarrhea rates are positively correlated with increased temperature, and show a complex relationship with precipitation. Although climate change will likely increase rates of diarrheal diseases on average, there is a poor mechanistic understanding of the underlying disease transmission processes and substantial uncertainty surrounding current estimates. This makes it difficult to recommend appropriate adaptation strategies. We review the relevant climate-related mechanisms behind transmission of diarrheal disease pathogens and argue that systems-based mechanistic approaches incorporating human, engineered and environmental components are urgently needed. We then review successful systems-based approaches used in other environmental health fields and detail one modeling framework to predict climate change impacts on diarrheal diseases and design adaptation strategies.

Sensitive assays enable detection of serum IgG antibodies against Clostridium difficile toxin A and toxin B in healthy subjects and patients with Clostridium difficile infection

BACKGROUND

Pathogenic Clostridium difficile produces two proinflammatory exotoxins, toxin A and toxin B. Low level of serum antitoxin IgG antibodies is a risk factor for the development of primary and recurrent C. difficile infection (CDI).

RESULTS

We developed and validated two sensitive, titer-based electrochemiluminescence assays for the detection of serum antibody levels against C. difficile toxins A and B. These assays demonstrated excellent precision. The sensitivity of the assays allowed the detection of antitoxin A and antitoxin B IgG antibodies in all tested serum samples during assay validation.

CONCLUSION

The validated titer-based assays enable assessment of antitoxin A and antitoxin B IgG antibodies as potential biomarkers to identify patients with CDI at increased risk for CDI recurrence.

The effectiveness and safety of treatments used for acute diarrhea and acute gastroenteritis in children: protocol for a systematic review and network meta-analysis

BACKGROUND

Acute diarrhea and acute gastroenteritis (AD/AGE) are common among children in low- and middle-income countries (LMIC) and high-income countries (HIC). Supportive therapy including maintaining feeding, prevention of dehydration, and use of oral rehydration solution (ORS), is the mainstay of treatment in all children. Several additional treatments aiming to reduce the episode duration have been compared to placebo, but the differences in effectiveness among them are unknown.

METHODS AND ANALYSIS

We will conduct a systematic review of all randomized controlled trials evaluating the use of zinc, vitamin A, probiotics, prebiotics, synbiotics, racecadotril, smectite, and fermented and lactose-free milk/formula for AD/AGE treatment in children. The primary outcomes are diarrhea duration and mortality. Secondary outcomes are diarrhea lasting 3 or 7 days, stool frequency, treatment failure, hospitalizations, and adverse events. We will search MEDLINE, Ovid EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials (CENTRAL), and LILACS through Ovid, as well as grey literature resources. Two reviewers will independently screen titles and abstracts, review full texts, extract information, and assess the risk of bias (ROB) and the confidence in the estimate (with the grading of recommendations, assessment, development, and evaluation [GRADE] approach). Results will be summarized narratively and statistically. Subgroup analysis according to HIC vs. LMIC, age, nutrition status, and ROB is planned. We will perform a Bayesian network meta-analysis to combine the pooled direct and indirect treatment effect estimates for each outcome, if adequate data is available.

DISCUSSION

This is the first systematic review and network meta-analysis that aims to determine the relative effectiveness of pharmacological and nutritional treatments for reducing the duration of AD/AGE in children. The results will help to reduce the uncertainty of the effectiveness of the interventions, find knowledge gaps, and/or encourage further research for other therapeutic options.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number: CRD42015023778.

Core 2 mucin-type O-glycan inhibits EPEC or EHEC O157:H7 invasion into HT-29 epithelial cells

Background

How host cell glycosylation affects EPEC or EHEC O157:H7 invasion is unclear. This study investigated whether and how O-glycans were involved in EPEC or EHEC O157:H7 invasion into HT-29 cells.

Results

Lectin histochemical staining confirmed stronger staining with PNA, which labeled Galβ1, 3 GalNAc (core 1 structure) in HT-29-Gal-OBN and C2GnT2-sh2/HT-29 cells, compared with control cells. EPEC or EHEC O157:H7 invasion into HT-29 and its derived cells was based on the intracellular presence of GFP-labeled bacteria. The differentiation of HT-29 cells led to a reduction in EPEC internalization compared with HT-29 cells (p < 0.01). EPEC or EHEC O157:H7 invasion into HT-29-OBN and HT-29-Gal-OBN cells increased compared with HT-29 and HT-29-Gal cells (p < 0.05 and p < 0.01). Core 2 O-glycan-deficient HT-29 cells underwent a significant increase in EPEC (p < 0.01) or EHEC O157:H7 (p < 0.05) invasion compared with control cells.

Methods

Bacterial invasion into cultured cells was determined by a gentamicin protection assay and a GFP-labeled bacteria invasion assay. O-glycans biosynthesis was inhibited by benzyl-α-GalNAc, and core 2 O-glycan-deficient HT-29 cells were induced by C2GnT2 interference.

Conclusion

These data indicated that EPEC or EHEC O157:H7 invasion into HT-29 cells was related to their O-glycosylation status. This study provided the first evidence of carbohydrate-dependent EPEC or EHEC O157:H7 invasion into host cells.

Water use practices, water quality, and households' diarrheal encounters in communities along the Boro-Thamalakane-Boteti river system, Northern Botswana

BACKGROUND

Some rural African communities residing along rivers use the untreated river water for domestic purposes, making them vulnerable to waterborne diseases such as diarrhea.

METHODS

We determined water use practices and water quality, relating them to prevalence of diarrhea in communities along the Boro-Thamalakane-Boteti river system, northern Botswana. A total of 452 households were interviewed and 196 water samples collected show during February, May, September, and December 2012 in settlements of Boro, Maun, Xobe, Samedupi, Chanoga, and Motopi. Information was sought on water use practices (collection, storage, and handling) and diarrheal experience using questionnaires. Water quality was assessed for physicochemical and microbiological parameters using portable field meters and laboratory analysis, respectively.

RESULTS

All (100%) of the river water samples collected were fecally contaminated and unsuitable for domestic use without prior treatment. Samples had Escherichia coli (E.coli) and fecal streptococci levels reaching up to 186 and 140 CFU/100 ml, respectively. Study revealed high dependence on the fecally contaminated river water with low uptake of water treatment techniques. Up to 48% of households indicated that they experience diarrhea, with most cases occurring during the early flooding season (May). Nonetheless, there was no significant relationship between river water quality and households' diarrheal experience across studied settlements (p > 0.05). Failure to treat river water before use was a significant predictor of diarrhea (p = 0.028).

CONCLUSIONS

Even though the river water was unsafe for domestic use, results imply further recontamination of water at household level highlighting the need for simple and affordable household water treatment techniques.

Core 2 Mucin-Type O-Glycan Is Related to EPEC and EHEC O157:H7 Adherence to Human Colon Carcinoma HT-29 Epithelial Cells

BACKGROUND AND AIM

The roles of host glycosylation in interactions with EPEC and EHEC O157:H7 are largely unclear; this study examined whether O-glycans are involved in EPEC and EHEC O157:H7 adherence to HT-29 cells.

METHODS

Bacterial adherence to the cultured cells was determined using the direct co-staining of adherent bacteria and host cells, the adherent bacteria plating, and/or the direct fluorescent observation of the adherent GFP-labeled bacteria.

RESULTS

A comparison of the adherence of EPEC and EHEC O157:H7 to HT-29-Gal and HT-29 cells indicated that the differentiation of HT-29 cells led to a reduction in the adherence of EPEC and EHEC O157:H7. EPEC and EHEC O157:H7 adhesion decreased after the abrogation of O-glycan biosynthesis mediated by benzyl-α-GalNAc treatment. Core 2 O-glycan-deficient HT-29 cells induced by C2GnT2 knockdown had a significant reduction in EPEC and EHEC O157:H7 adhesion in C2GnT2-sh2/HT-29 cells compared with HT-29 and shRNA-Ctr/HT-29 cells. MUC2 expression in benzyl-α-GalNAc-treated HT-29 cells was significantly reduced but unchanged in C2GnT2-deficient HT-29 cells. EPEC or EHEC O157:H7 infection in C2GnT2-deficient HT-29 cells deteriorated the epithelial barrier function. The occludin expression in the shRNA-Ctr/HT-29 and C2GnT2-sh2/HT-29 cells after infection with EPEC or EHEC O157:H7 was pyknic and discontinuous at the cell surface compared with its continuous distribution of control cells. These data indicate that EPEC and EHEC O157:H7 adherence to HT-29 cells is related to mucin-type core 2 O-glycan.

CONCLUSIONS

This study provides the concepts toward the design of carbohydrate-dependent inhibition of EPEC and EHEC O157:H7 adhesion to human intestinal epithelial cells.