Bacterial Enteropathogens Research Articles

Role of Fecal Microbiota Transplantation in Treating Inflammatory Bowel Disease and Clostridium difficile Infection: Narrative Review

Introduction: Fecal microbiota transplantation (FMT) is a therapeutic method where fecal microbiota from a healthy donor is transferred to a patient in the hopes of restoring normal, healthy microbiota of the gut. FMT is a promising treatment option for patients with medical conditions causing dysbiosis such as inflammatory bowel disease (IBD), Clostridium Difficile infection (CDI), metabolic syndrome, obesity, and irritable bowel syndrome. Over the years, studies were conducted to test its efficacy in other clinical conditions associated with normal bowel microbiome depletion. Methods: This narrative review summarizes the available efficacy and safety data on the use of FMT in IBD and C. diff patients. We completed an extensive literature search on PubMed, Google Scholar, Scopus, and Cochrane library electronic databases. Results: In most studies, patients received antibiotics before FMT. In studies retrieved, donors were related to recipients (relatives, friends, partners), whereas stool from unrelated donors was used less frequently. Pre-transplant screening procedures include serological testing for viruses (e.g., hepatitis A/B/C viruses, EBV, CMV, and HIV) and stool testing for C. difficile toxins, parasites, ova, and common bacterial enteropathogens. According to our search, several routes of administration were reported: enema, colonoscopy in seven studies, gastroscopy, nasojejunal tube, and nasogastric tube. Data support a positive effect of FMT on the outcome of IBD in at least some patients. In the majority of studies reviewed, IBD patients showed decreasing rates of remission/response over time. Our search shows FMT was well tolerated. Most common adverse events were abdominal pain, cramping, bloating, flatulence, increased stool frequency, and fever within days of transplant. The majority were self-resolving. Stool preparation is required for FMT with the minimum amount of stool infusate needed being 50g. Conclusion: Low recurrence rates of CDI and successful restoration of gut microbiota has proven FMT an innovative and popular treatment. Infectious Diseases Society of America and Society for Healthcare Epidemiology of America made updated guidelines in 2017 to recommend FMT for treatment of people with >2 recurrences of CDI despite standard antibiotic treatment. Successful FMT procedures can save the healthcare system thousands of dollars with fewer hospitalizations and frequent antibiotic prescriptions. Further studies focused on long-term outcomes and safety are also warranted.2745 Figure 1. Preparation of fecal materials for fecal microbiota transplantation.

Characterization of Swedish Campylobacter coli clade 2 and clade 3 water isolates.

Campylobacter jejuni and Campylobacter coli are important bacterial enteropathogens. Poultry is the best‐known reservoir for Campylobacter infection but natural bodies of water have also been shown to be important pathways for transmission. Campylobacter can survive in cold water but most of the studies have focused on C. jejuni only. In this paper, we take a closer look at the biology and water survival strategies of C. coli. Eight C. coli isolates cultivated from raw (incoming) surface water at water plants in Sweden were characterized using whole‐genome sequencing and phenotypical assays. Phylogenetic analysis assigned the Swedish water isolates to clades 2 and 3, known to include C. coli of environmental origin. In addition, 53 earlier published sequences of C. coli clade 2 and 3 from environmental waters were included for in silico analyses. Generally, clade 2 isolates had larger genomes, which included a functional tricarballylate utilization locus, while clade 3 isolates contained different genes involved in oxidative stress as well as putative virulence factors. The Swedish water isolates of clade 2 formed large, blurry bacterial colonies on agar, whereas clade 3 colonies were smaller. All Swedish isolates were motile, but clade 3 isolates formed larger motility zones on soft agar, and none of these isolates produced biofilm. Although water survival varied between the analyzed isolates, there were hardly any clade‐specific significant differences. Our results highlight the diversity of C. coli in general, and show differences in metabolic capabilities and ways to handle oxidative stress between clade 2 and 3 water isolates.

Enteric pathogens and associated risk factors among under-five children with and without diarrhea in Wegera District, Northwestern Ethiopia.

IntroductionChildhood diarrhea is highly prevalent in slums in developing countries, but it remains understudied. The objectives of this study were to explore the prevalence of Giardia, rotavirus and bacterial enteropathogens among diarrheic and non-diarrheic children and investigate socio-environmental determinants of diarrhea in two Ethiopian towns.MethodsA cross-sectional study was conducted from June to October 2016. Prevalence of childhood diarrhea was established using information gathered during interviews with mothers/guardians. Saline wet mounts of fresh stool samples were used to test for the presence of Giardia. Stool samples were cultured on MacConkey agar and suspected colonies were characterized using biochemical tests. Susceptibility testing was done by the disk diffusion method. ELISA was used to screen for rotavirus.ResultsA total of 225 children were included in this study. Four enteropathogens (Giardia, rotavirus, Shigella and Salmonella) were identified from 31% (35/112) diarrheic and 12% (14/113) from non-diarrheic children (p < 0.001). The prevalence of rotavirus infection was 18.0% among diarrheic children and 3.3% among non-diarrheic children unvaccinated against rotavirus (p < 0.01). The prevalence of Giardia was 21.0% among diarrheic and 8.0% among non-diarrheic children (p < 0.01). Diarrheic children had significantly higher rates of bloody stool (p < 0.02), vomiting, fever and breastfeeding for children beyond 23 months of age (p < 0.001). Giardia and rotavirus were identified in more diarrheic than non-diarrheic children.ConclusionThe high prevalence of Giardia and rotavirus in the study area indicates the need for coordinated healthcare activities in the two communities. Vaccination against rotavirus infections and educational interventions are recommended.

The clinical features and infectious etiologies of acute diarrhea in immunocompromised hosts

Objectives The acute diarrhea is a common complaint among immunocompromised hosts, and may cause life threatening event. The infectious etiologies vary depending on virus, bacteria, and parasites. The most common etiology of acute gastroenteritis is known as enteric virus in Korea. But there are few studies about the infectious etiology of acute gastroenteritis in immunocompromised hosts. The aim of this study was to investigate the infectious etiologies of acute diarrhea in immunocompromised hosts. Methods Seventy three patients were enrolled prospectively in a university hospital from January 2013 to July 2014. Immunocompromised hosts included above 65-year-old people, patients with chronic diseases, solid organ or stem cell transplants, solid organ malignancies, hematologic malignancies, immunosuppressive or steroid taking patients. The clinical data were collected and stool samples collected during diarrhea were undergone laboratory analysis for enteric viruses and bacterial enteropathogens including Salmonella spp., Shigella spp., and Clostridium difficile. Results Fifty five patients were analyzed as follows : above 65 year-old people were 36 cases (66%), previous antibiotic usage was 22 cases (41.5%). 44 cases (81.1%) were admitted to general ward whereas 9 cases to ICU (17%). 41 cases (73.6%) were treated with antibiotics. Positive C. difficile toxin assays were 6 cases (11.9%). Other infectious etiologies were not found. Conclusions C. difficile infection was more common infectious etiology while enteric viruses and other bacteria are not associated with acute diarrhea among immunocompromised hosts in this study. So C. difficile infection must be considered preferentially in immunocompromised hosts with acute diarrhea.

Risk Factors and Clinical Outcomes of Cancer Patients with Clostridium difficile Associated Diarrhea Co-infected with a Second Enteropathogen

BackgroundCancer patients are at an increased risk for C. difficile infection (CDI) which is often identified along with other enteropathogens. The impact of co-infections on outcomes has not been established in this population. We compared the risk factors and clinical characteristics of patients with CDI monoinfection (CDIM) and patients coinfected with bacterial (CDIB) or viral (CDIV) enteropathogens.MethodsAdult patients presenting with primary or recurrent CDI (n = 88) identified on a two-step GI multiplex assay (Biofire) followed by toxin A/B EIA, were classified into CDIM (n = 66), CDIB (n = 12), and CDIV (n = 10) groups. Demographic and clinical data were collected and risk factors and outcomes compared by Fisher’s exact test, ANOVA, and the Kruskal–Wallis test. CDI severity was determined using Zar’s criteria, presence of bacteremia, and ICU stay.ResultsDuring the study period, 2,017 diarrheal samples were submitted to the microbiology laboratory. An enteric pathogen was identified in 311 (15%) patients. CDI was identified in 88 cases of which 22 (25%) had a second pathogen. CDIM was found in 66 (21%), CDIB in 12 (4%), and CDIV in 10 (3%) subjects. The most common co-pathogens identified were diarrheagenic E. coli in the CDIB group (9/12, 75%) and norovirus in the CDIV group (8/10, 80%). Groups were similar in terms of demographics, number of recurrences, health care acquisition, co-morbidities, disease severity, serum creatinine at presentation, presence of toxin by EIA, and mortality. Patients with CDIM were more likely to have a recent hospitalization than the CDIB group (44/66 67% vs.. 3/12 25%, P = 0.01). Clinical symptoms at presentation were similar for the three groups except for nausea which was more common in the CDIV group when compared with CDIM (8/10, 80% vs. 25/66, 38%; P = 0.02). The use of proton pump inhibitors was similar in the three groups. There was however, a higher proportion of patients taking GABA-like drugs within 90 days among the CDIB patients (10/12, 83%) than the group with CDIM (26/66, 40%) P = 0.01.ConclusionIn CDI cancer patients, co-infection with other enteropathogens is common. Patients with CDIB were less likely to have a recent admission to a health care facility. The use of GABA-like drugs was associated with a higher risk of bacterial co-infection.Disclosures All authors: No reported disclosures.

Changes in the intestinal microbiota following the administration of azithromycin in a randomised placebo-controlled trial among infants in south India

Macrolides are among the most widely prescribed antibiotics worldwide. However, their impact on the gut’s bacterial microbiota remains uncertain. We characterised the intestinal microbiota in 6–11 month-old infants in India who received a 3-day course of azithromycin or placebo during a randomised trial of oral poliovirus vaccine immunogenicity (CTRI/2014/05/004588). In 60 infants per study arm, we sequenced the V4 region of the bacterial 16S rRNA gene in stool samples collected before and 12 days after finishing treatment. We also tested for the presence of common bacterial, viral, and eukaryotic enteropathogens in the same samples using real-time PCR in a Taqman array card (TAC) format. Azithromycin induced a modest decline in microbiota richness and a shift in taxonomic composition driven by a reduction in the relative abundance of Proteobacteria and Verrucomicrobia (specifically Akkermansia muciniphila). The former phylum includes pathogenic strains of Escherichia coli and Campylobacter spp. that declined in prevalence based on the TAC assay. These findings differ from previous observations among older children and adults in Europe and North America, suggesting that the effects of azithromycin on the bacterial microbiota may be specific to the age and geographic setting of its recipients.

Determination of the prevalence of viral aetiology of diarrhea in children less than 5 years of age in Baghdad province

Determination the prevalence of viral, parasitic and bacterial etiology of gastroenteritis in children less than 5 years of age with diarrhea in various hospitals of Baghdad province. A total of 250 stool samples were collected from various hospitals of Baghdad province .Samples were investigated for bacterial and parasitic enteropathogens using microscopic examination. Bacterial culture of stool samples was done in different culture media including MacConkey, XLD, DCA, TCBS and campylobacter media, TCBS and selenite F broth and bacterial growth was examined by analytical profile index (Api20E) system , commercial antisera and colonies characteristics. Enzyme immunoassays were used to identify Group A rotavirus ,Astrovirus and enteric adenovirus Out of 250, 106 children (42.4%) were diagnosed as viral infection of which Rotavirus was found in the majority of cases 91 (36.4%), Adenovirus was detected in 15(6%) patients. bacterial causes were 63 (25.2%) of which 36 (14.4%) were Escherichia coli (ETEC), 12 (4.8%) were Shigella flexneri , 6(2.4%) were Campylobacter jejunii and 9(3.6) were Salmonella enteritidis . Entamoeba histolytica 22 (8.8%) and Giardia lamblia 22 (8.8%) were the most frequent parasite which isolated from all diarrheal stool specimens. Also from total of 250 samples, 40 samples (16%) were dysenteric stool specimens (bloody diarrhea) and the most common pathogens isolated from dysenteric stool specimens were E.histolytica 22(8.8%), Shigella flexneri 12(4.8%) and Campylobacter jejunii 6 (2.4%). The current study revealed a high prevalence of rotavirus as most common cause of diarrhoea in children less than 5 years of age.

Microbial pathogens associated with acute childhood diarrhoea in Kumasi, Ghana

BackgroundDiarrhoeal diseases are among the most frequent causes of morbidity and mortality in children worldwide, especially in sub-Saharan Africa. This case–control study was conducted to investigate the bacterial, viral and parasitic pathogens associated with acute diarrhoea among children attending three health facilities in Kumasi, Ghana.MethodsStool specimens were collected from 240 children under 5 years of age visiting hospitals in Kumasi, Ghana due to acute diarrhoea and from 107 healthy controls of similar age. Both intestinal and malaria parasites were diagnosed by microscopy whereas rota- and adenoviruses were identified by stool antigen immunochromatograhic testing. Bacterial enteropathogens were detected by conventional culture techniques.ResultsOf all subjects, 23 (6.6%) were positive for malaria parasitaemia, 139 (40.1%) had at least one bacterial agent in their stool and 25 (7.2%) had ova or parasites. Subjects infected with malaria had the highest odds of having diarrhoea [12.0 (95% CI 1.56, 92.35)] followed by those with rotaviruses [4.4 (95% CI 2.05, 9.47)] and bacterial infection [4.99 (95% CI 1.45, 17.17)].ConclusionIn conclusion, this study was unique as it looked at the three groups of pathogens (parasites, viruses and bacteria) that cause acute diarrhoea in children in the Kumasi metropolis of Ghana. This study has shown for the first time since 2004 that malaria parasitaemia, rotavirus and bacterial infections still remain common pathogens associated with acute childhood diarrhoea in the Kumasi metropolis of Ghana.

What happened to Koch's postulates in diarrhoea?

In 1890, Robert Koch has formulated postulates describing what criteria a parasite has to fulfil to qualify as an aetiological agent for an infectious disease. Since then Koch's postulates have experienced reformulations by nearly every generation of microbiologists reflecting new discoveries changing the understanding of infectious diseases pathogenesis. The latest addition to this discussion is the role of the host commensal microbiota in turning infections into disease. After an overview of the historical developments of the postulates, data on diarrhoea aetiology from Bangladesh with respect to Koch's postulates were analysed. In countries with a low environmental hygiene standard, some recognized bacterial enteropathogens appear as a necessary, but not sufficient condition for diarrhoea. The possibility emerges that the loss of a physiological commensal gut microbiota equilibrium ('dysbiosis') is an important co-factor for some bacterial pathogens to induce diarrhoea. Koch's hypothesis '1 pathogen + 1 host = 1 disease' is therefore better formulated as 'X (pathogen/s) + Y (local milieu) + Z (individual host susceptibility) = disease'.

High-avidity IgA protects the intestine by enchaining growing bacteria.

Vaccine-induced high-avidity IgA can protect against bacterial enteropathogens by directly neutralizing virulence factors or by poorly defined mechanisms that physically impede bacterial interactions with the gut tissues ('immune exclusion'). IgA-mediated cross-linking clumps bacteria in the gut lumen and is critical for protection against infection by non-typhoidal Salmonella enterica subspecies enterica serovar Typhimurium (S. Typhimurium). However, classical agglutination, which was thought to drive this process, is efficient only at high pathogen densities (≥108 non-motile bacteria per gram). In typical infections, much lower densities (100-107 colony-forming units per gram) of rapidly dividing bacteria are present in the gut lumen. Here we show that a different physical process drives formation of clumps in vivo: IgA-mediated cross-linking enchains daughter cells, preventing their separation after division, and clumping is therefore dependent on growth. Enchained growth is effective at all realistic pathogen densities, and accelerates pathogen clearance from the gut lumen. Furthermore, IgA enchains plasmid-donor and -recipient clones into separate clumps, impeding conjugative plasmid transfer in vivo. Enchained growth is therefore a mechanism by which IgA can disarm and clear potentially invasive species from the intestinal lumen without requiring high pathogen densities, inflammation or bacterial killing. Furthermore, our results reveal an untapped potential for oral vaccines in combating the spread of antimicrobial resistance.

Resistant pathogens as causes of traveller's diarrhea globally and impact(s) on treatment failure and recommendations.

: Diarrhea is a frequent clinical syndrome affecting international travellers. Bacterial etiologic agents have a long history of emergent antimicrobial resistance against commonly used antibiotics. Current approaches applying first-line antimicrobial therapy are being challenged by increasingly resistant organisms. This review summarizes recent epidemiological and clinical evidence of antibiotic resistance among enteropathogens causing traveller's diarrhea and the subsequent impact on current treatment recommendations. : The PubMed database was systemically searched for articles related to antibiotic susceptibility and diarrheal pathogens. : Antibiotic resistance related to travellers' diarrhea has increased in recent years. Most notably, fluoroquinolone resistance has expanded from the Campylobacter -associated cases well documented in Southeast Asia in the 1990s to widespread occurrence, as well as increases among other common bacterial enteropathogens including, enterotoxigenic and enteroaggregative Escherichia coli , Shigella and non-typhoidal Salmonella . Multidrug resistance among enteropathogenic Enterobacteriacae and Campylobacter species create further challenges with the selection of empiric therapy. Treatment failures requiring early use of alternative agents, as well as delayed recovery comparable to placebo rates emphasize the impact of antimicrobial resistance on effective treatment. : Although there are limitations in the available data, the increasing antibiotic resistance and adverse impact on clinical outcome require continued surveillance and reconsideration of practice guidelines.

Helminth-induced alterations of the gut microbiota exacerbate bacterial colitis.

Infection with the intestinal helminth parasite Heligmosomoides polygyrus exacerbates the colitis caused by the bacterial enteropathogen Citrobacter rodentium. To clarify the underlying mechanism, we analyzed fecal microbiota composition of control and helminth-infected mice and evaluated the functional role of compositional differences by microbiota transplantation experiments. Our results showed that infection of Balb/c mice with H. polygyrus resulted in significant changes in the composition of the gut microbiota, characterized by a marked increase in the abundance of Bacteroidetes and decreases in Firmicutes and Lactobacillales. Recipients of the gut microbiota from helminth-infected wide-type, but not STAT 6-deficient, Balb/c donors had increased fecal pathogen shedding and significant worsening of Citrobacter-induced colitis compared to recipients of microbiota from control donors. Recipients of helminth-altered microbiota also displayed increased regulatory T cells and IL-10 expression. Depletion of CD4+CD25+ T cells and neutralization of IL-10 in recipients of helminth-altered microbiota led to reduced stool C. rodentium numbers and attenuated colitis. These results indicate that alteration of the gut microbiota is a significant contributor to the H. polygyrus-induced exacerbation of C. rodentium colitis. The helminth-induced alteration of the microbiota is Th2-dependent and acts by promoting regulatory T cells that suppress protective responses to bacterial enteropathogens.

Identification and antimicrobial resistance patterns of bacterial enteropathogens from children aged 0\u201359 months at the University Teaching Hospital, Lusaka, Zambia: a prospective cross sectional study

BackgroundBacterial diarrhoeal disease is among the most common causes of mortality and morbidity in children 0–59 months at the University Teaching Hospital in Lusaka, Zambia. However, most cases are treated empirically without the knowledge of aetiological agents or antimicrobial susceptibility patterns. The aim of this study was, therefore, to identify bacterial causes of diarrhoea and determine their antimicrobial susceptibility patterns in stool specimens obtained from the children at the hospital.MethodsThis hospital-based cross-sectional study involved children aged 0–59 months presenting with diarrhoea at paediatrics wards at the University Teaching Hospital in Lusaka, Zambia, from January to May 2016. Stool samples were cultured on standard media for enteropathogenic bacteria, and identified further by biochemical tests. Multiplex polymerase chain reaction was used for characterization of diarrhoeagenic Escherichia coli strains. Antimicrobial susceptibility testing was performed on antibiotics that are commonly prescribed at the hospital using the Kirby-Bauer disc diffusion method, which was performed using the Clinical Laboratory Standards International guidelines.ResultsOf the 271 stool samples analysed Vibrio cholerae 01 subtype and Ogawa serotype was the most commonly detected pathogen (40.8%), followed by Salmonella species (25.5%), diarrhoeagenic Escherichia coli (18%), Shigella species (14.4%) and Campylobacter species (3.5%). The majority of the bacterial pathogens were resistant to two or more drugs tested, with ampicillin and co-trimoxazole being the most ineffective drugs. All diarrhoeagenic Escherichia coli isolates were extended spectrum β-lactamase producers.ConclusionFive different groups of bacterial pathogens were isolated from the stool specimens, and the majority of these organisms were multidrug resistant. These data calls for urgent revision of the current empiric treatment of diarrhoea in children using ampicillin and co-trimoxazole, and emphasizes the need for continuous antimicrobial surveillance as well as the implementation of prevention programmes for childhood diarrhoea.

Antiprotozoal, Antibacterial and Antidiarrheal Properties from the Flowers of Chiranthodendron pentadactylon and Isolated Flavonoids.

Background:Chiranthodendron pentadactylon Larreat. (Sterculiaceae) is a Mexican plant used in traditional medicine for the treatment of heart disease symptoms and infectious diarrhea.Objective:To evaluate in vitro antiprotozoal and antibacterial activities and in vivo antidiarrheal activity from the flowers of C. pentadactylon using the extract, fractions, and major isolated flavonoids.Materials and methods:Bioassay-guided fractionation of the methanol extract of C. pentadactylon (MECP) led to the isolation of five flavonoids, tiliroside, astragalin, isoquercitrin, (+)-catechin, and (-)-epicatechin. Antimicrobial activities were tested on two protozoa (Entamoeba histolytica and Giardia lamblia) and nine bacterial enteropathogens (two Escherichia coli strains, two Shigella sonnei strains, two Shigella flexneri strains, two Salmonella sp. strains, and Vibrio cholerae) isolated from feces of children with acute diarrhea or dysentery and resistant to chloramphenicol. Also, antidiarrheal activity was tested on cholera toxin-induced diarrhea in male Balb-c mice.Results:Epicatechin was the most potent antiamoebic and antigiardial compound with IC50 values of 1.9 μg/mL for E. histolytica and 1.6 μg/mL for G. lamblia; tiliroside showed moderate antiprotozoal activity against both protozoan. In contrast, in the antibacterial activity, tiliroside was the most potent compound on all microorganisms with minimum inhibitory concentration values less than 0.7 mg/mL. In the case of cholera toxin-induced diarrhea, epicatechin was the most potent flavonoid with IC50 of 14.7 mg/kg.Conclusion:Epicatechin and tiliroside were the flavonoids responsible for antimicrobial andantidiarrheal activities of C. pentadactylon. Its antiprotozoal, antibacterial, and antidiarrheal properties are in good agreement with the traditional medicinal use of C. pentadactylon for the treatment of infectious diarrhea.SUMMARY Epicatechin was the most potent antiamoebic and antigiardial compound with IC50 values of 1.9 μg/mL for E. histolytica and 1.6 μg/mL for G. lamblia.Tiliroside showed antibacterial activity against all microorganisms tested with MIC values less than 0.7 mg/mL.Epicatechin was the most potent flavonoid on cholera toxin-induced diarrhea with IC50 of 14.7 mg/kg. Abbreviations used: MECP: Methanol extract of C. pentadactylon

Case-Control Pilot Study on Acute Diarrheal Disease in a Geographically Defined Pediatric Population in a Middle Income Country.

Introduction Acute diarrheal disease (ADD) is a common cause of morbidity and mortality in children under 5 years of age. Understanding of the etiology of ADD is lacking in most low and middle income countries because reference laboratories detect limited number of pathogens. The objective of this study was to determine the feasibility to conduct a comprehensive case-control study to survey diarrheal pathogens among children with and without moderate-to-severe ADD. Materials and Methods Microbiology and molecular-based techniques were used to detect viral, bacterial, and parasitic enteropathogens. The study was conducted in Bucaramanga, Colombia, after Institutional Review Board approval was obtained. Results Ninety children less than 5 years of age were recruited after a written informed consent was obtained from parents or guardians. Forty-five subjects served as cases with ADD and 45 as controls. Thirty-six subjects out of 90 (40.0%) were positive for at least one enteropathogen, that is, 20 (44.4%) cases and 16 (35.5%) controls. Conclusions The three most common enteric pathogens were enteroaggregative E. coli (10.0%), Norovirus (6.7%), and Salmonella spp. (5.6%). The E. coli pathogens were 18.8% of all infections making them the most frequent pathogens. Half of ADD cases were negative for any pathogens.

Prevalence and factors associated with the occurrence of bacterial enteropathogens in suckling piglets in farrow-to-finish herds

The aim of the study was to determine both environmental and infectious factors, influencing occurrence of bacterial enteropathogens in suckling piglets. For this purpose, a cross-sectional study in 70 Polish...

Epidemiology of Diarrheal Illness in Pediatric Oncology Patients.

Diarrhea is common in children with cancer, but this has not been systematically studied to date. Remnant stool samples collected between January 2010 and June 2011 from pediatric oncology patients with diarrhea were tested for bacterial, viral, and parasitic enteropathogens using a combination of standard-of-care (SOC) diagnostic tests, including broad-range, real-time polymerase chain reaction (PCR) assays for adenoviruses, astroviruses, and sapoviruses and 2 commercially available multiplexed PCR assays. Corresponding demographic and clinical data were abstracted from patients' medical records. One hundred fourteen episodes of diarrhea in 93 patients (median age, 3.7 years; range, 0.2-18.8) were included in the study. No patients died, but morbidity was significant. A total of 158 potential pathogens were detected in 114 diarrhea episodes, with >1 organism in one third of these; the most common were Clostridium difficile, noroviruses, adenoviruses, and astroviruses. Clostridium difficile, in combination with norovirus or adenovirus, was most common when >1 pathogen was detected. When both studies were obtained, SOC and broadly multiplexed PCR tests were concordant in 64 episodes (56%). Forty-five pathogens (28%) were identified retrospectively by broadly multiplexed PCR assays only. A total of 19 (13%) were detected by SOC real-time PCR assays but not by either commercially available multiplexed PCR assay. Most pediatric oncology patients in this study had 1 or more potential infectious causes for their diarrhea. Additional studies are warranted to understand the natural history of gastroenteritis in this patient population. Although broadly multiplexed PCR assays offer some advantages over conventional testing, there may be disadvantages to their use for the diagnosis of infectious gastroenteritis that are unique to pediatric oncology patients.

Bacterial Intestinal Superinfections in Inflammatory Bowel Diseases Beyond Clostridum difficile.

Besides genetics and environmental factors, intestinal microbiota seem to play a major role in the pathogenesis of inflammatory bowel diseases. For many decades, it has been said that some enteropathogens may even trigger both inflammatory bowel disease development and disease flares. For this reason, stool testing had been performed in inflammatory bowel disease flares but current guidelines only recommend to rule out Clostridium difficile infection and there is no clear advice for other enteropathogens given that the scarce available evidence points at a low prevalence of this sort of intestinal superinfections with no clear impact on disease course. The present article reviews the current knowledge about the role of bacterial enteropathogens on disease pathogenesis and flares beyond C. difficile.

Pathogen Presence in European Starlings Inhabiting Commercial Piggeries in South Australia.

The majority of bacterial diarrhea-causing illnesses in domestic pigs result from infection with Escherichia coli, Salmonella spp., or Campylobacter spp. These bacterial enteropathogens also correspond with the most-common bacteria isolated from wild birds. Additionally, viral pathogens such as avian influenza virus (AIV), West Nile virus (WNV, including Kunjin disease), and Newcastle disease virus (NDV) may also be carried and transmitted by birds in Australia. Introduced European starlings (Sturnus vulgarus) are one of the most-frequently reported birds on piggeries in Australia. The presence of the three bacterial pathogens, Salmonella spp., Campylobacter spp., and Escherichia coli , as well as the three viral pathogens AIV, WNV, and NDV, were evaluated in starlings captured on four commercial piggeries in South Australia. A total of 473 starlings were captured on the four piggeries in 2008 and 2009. A cloacal swab was taken from each bird and cultured for bacterial identification, with follow-up serotyping of any positives, whilst fifty samples were analyzed by PCR for the three target viral pathogens. There was no AIV, WNV, or NDV detected in the 50 starlings sampled. Escherichia coli was found to be present in the starling populations on all four piggeries whilst Salmonella spp. and Campylobacter jejuni were found to be present only in the starling population sampled on one piggery. Serotyping identified pig-pathogenic strains of the bacteria. The prevalence of these production-limiting bacterial pathogens in starlings, coupled with the large starling populations often found inside piggeries during daylight hours in the summer months, presents a disease transmission risk and jeopardizes piggery disease management. Removal of starlings from agricultural enterprises (as shown by international studies), or prevention of starling access to animal feed and water, could substantially reduce the risk of transmission of enterobacterial pathogens from starlings to livestock.

Etiological Spectrum of Acute Gastroenteritis in Children Less Than 5 Years of Age with Special Reference to Norovirus

To clarify the infectious etiology of acute gastroenteritis in children less than 5 years of age, we conducted a 1-year prospective case-control study. Stools from150 children with diarrhea and 150 age-matched controls admitted in the hospital for illness involving system other than that of gastrointestinal tract were examined, and their parents were interviewed regarding concerning symptoms. Samples were investigated for parasitic enteropathogens using microscopic examination and bacterial enteropathogens using conventional culture techniques. ELISA was performed for Rotavirus, adenovirus, astrovirus and norovirus were detected by PCR. Overall, a potential pathogen was found in 56.6% of the cases and 4% of controls.. The results indicated that noroviruses (4%) were less common than rotaviruses(24.6%), EPEC (4.6%), and V.Cholerae(4%) but more frequent than astroviruses (2.6%), adenoviruses(3.3%), Giardia lambia(2%) and Shigella spp.(1.3%). In our study it was found that acute gastroenteritis in children less than 5 years is due to viral etiology, where Rotavirus was predominant cause which points towards the need for a vaccine for this pathogen . While EPEC, Vibrio cholerae and Shigella represent the bacterial etiology of pediatric acute gastroenteritis. The role of norovirus as a emerging pathogen responsible for acute gastroenteritis in children needs to be assesed further.