Cause Of Diarrhea In Children Research Articles

A case of rotavirus infection-associated immune thrombocytopenic purpura

Rotavirus gastroenteritis is one of the most common abacterial causes of childhood diarrhea. Typical course of rotavirus infection in all ages of patients consists of 2-3 days of lasting fever, vomiting and then subsequent development of watery bloodless diarrhea. Rotavirus infection, especially gastroenteritis with severe vomiting, may cause critical and life-threatening dehydration. Extraintestinal involvement related to rotavirus infection is not commonly reported. Immune thrombocytopenia may happen after some of viral infections; however it has never been reported to be associated with wild-type rotavirus gastroenteritis to date. Here, we present a three-yearold patient with fever, vomiting, diarrhea and generalized purpura, which thought to be related to rotavirus infection.

Molecular Characterization of Enterotoxigenic Escherichia coli Isolates Recovered from Children with Diarrhea during a 4-Year Period (2007 to 2010) in Bolivia

Enterotoxigenic Escherichia coli (ETEC) is an important cause of childhood diarrhea. This study aimed to characterize ETEC strains isolated from Bolivian children aged <5 years according to enterotoxin profile, colonization factors (CFs), suggested virulence genes, and severity of disease. A total of 299 ETEC isolates recovered from children with diarrhea and 55 ETEC isolates from children without diarrhea (controls) were isolated over a period of 4 years. Strains expressing heat-labile toxin (LT) or heat-stable toxin (ST) alone were about equally common and twice as common as ETEC producing both toxins (20%). ETEC strains expressing human ST (STh) were more common in children aged <2 years, while ETEC strains expressing LT plus STh (LT/STh) were more frequent in 2- to 5-year-old children. Severity of disease was not related to the toxin profile of the strains. CF-positive isolates were more frequently identified in diarrheal samples than in control samples (P = 0.02). The most common CFs were CFA/I and CS14. CFA/I ETEC strains were more frequent in children aged <2 years than CS1+CS3 isolates and CS14 isolates, which were more prevalent in 2- to 5-year-old children. The presence of suggested ETEC virulence genes (clyA, eatA, tia, tibC, leoA, and east-1) was not associated with disease. However, east-1 was associated with LT/STh strains (P < 0.001), eatA with STh strains (P < 0.001), and tia with LT/STh strains (P < 0.001). A minor seasonal peak of ETEC infections was identified in May during the cold-dry season and coincided with the peak of rotavirus infections; this pattern is unusual for ETEC and may be important for vaccination strategies in Bolivia.

Cryptosporidiosis in Haiti: surprisingly low level of species diversity revealed by molecular characterization ofCryptosporidiumoocysts from surface water and groundwater

The protozoan parasite Cryptosporidium sp. has emerged as one of the most important water contaminants, causing waterborne outbreaks of diarrhoeal diseases worldwide. In Haiti, cryptosporidiosis is a frequent cause of diarrhoea in children under the age of five years, HIV-infected individuals, and people living in low socioeconomic conditions, mainly due to the consumption of water or food polluted by Cryptosporidium oocysts. The aim of this study was to detect and identify Cryptosporidium oocysts present in 12 water samples collected in Port-au-Prince and 4 water samples collected in Cap Haïtien. Initial detection consisted of immunomagnetic separation – immunofluorescence assay (IMS-IFA), which was confirmed by nested PCR, targeting the most polymorphic region of the 18S rRNA gene in 15/16 samples. Genotyping was performed by PCR-restriction fragment length polymorphism (RFLP) analysis and DNA sequencing. Under our working conditions, neither nested PCR-RFLP nor direct DNA sequencing revealed the expected species diversity, as only Cryptosporidium parvum was identified in the water samples studied. This study highlights the difficulty of detecting mixed populations of Cryptosporidium species in environmental samples.

Verotoxin -producing Escherichia coli Old Bug New Infections

EnteropathogenicEscherichia coli first discovered in the last century from the fecal flora of neonates.E.coli resides in human and animal intestine as normal flora.ETEC,EPEC and,EHEC strains cause severe potentially fatal disease . ETEC strains are important cause of childhood diarrhea in developing countries .EPEC infections are acquired by person to person and in the hospitals .EHECs Shiga producing strains that induce bloody diarrhea lead to HUS include renal failure microangiopathic haemolyticanaemia and thrombocytopenia.Vero toxin (Shiga like toxin) can directly damage renal and endothelial cells. The reservoir of EHEC strains is the gastrointestinal tract of young cattle and herbivorous mammals. Low infectious dose of EHEC strains facilitates the transmission of infection. Treatment of EHEC with antimicrobials have not shown clinical benefit rather cause increased production of toxins. Prevention of TD consists to avoid dietary indiscretions, hand washing before eating and eating only cooked food in endemic countries.

Epidemiological study of rotavirus diarrhea in Beijing area from 2010 to 2012

To investigate the epidemic of diarrhea caused by rotavirus infection among children treated at the Beijing Friendship Hospital in a period of 2 years. Stool samples were collected from 972 diarrheic children from January 2010 to January 2012. The antigen of rotavirus was detected by the gold imunochromatography assay (GICA). Among the samples studied, 370 out of 972 cases (38.1%) were positive for rotavirus antigen. The ratio of infected boys and girls was 2.14:1. Most infected children (91.4%) were under the age of two. The viral infection takes place all year round but breaks out mainly within a cold season that lasts from October through March, with a peak in November and December. Even in the spring and summer, however, its prevalence rates were quite significant among the children with diarrhea, ranging from 11.1% to 41.7%. In Beijing area, rotavirus is the major etiologic cause of diarrhea in children, especially in those under the age of 2. The peak prevalence occurs at any given time during the late fall and early spring seasons. It is necessary, therefore, to strengthen the surveillance of rotavirus infection in the spring and summer seasons in order not only to predict and prevent a potential outbreak in the end of the year, but also collect and provide more dynamic data for the further epidemiologic research of rotavirus diarrhea in the children.

English

BACKGROUND: Cryptosporidium has emerged as one of the major parasitic agents as a cause of diarrhoea in children. Various epidemiological factors have been described by different workers. Aims: This study was done to determine different epidemiological factors incriminated in cryptosporidiosis. Methods: Stool samples from 240 children with diarrhoea were examined for presence of Cryptosporidium. Wet mount examination, modified Ziehl- Neelsen (Z.N.) and Safranine-methylene blue staining methods were performed. For 177 samples, ELISA was also done. Detailed history of patients regarding their socioeconomic status and various sociodemographic factors was taken. Statistical Analysis: Chi-square and z tests were used to compare differences between the groups. A p value of ≤0.05 was considered significant. Results: Majority of patients were in Class IV socioeconomic group. Top-feeding, use of insanitary wells for drinking purposes, close association with animals, field defaecation and residence in rural areas were different factors that contributed to the spread of infection. Oocysts were present in 21 children on different staining procedures and 23 were positive by ELISA. Conclusion: Different sociodemographic factors like improper sanitation practices, drinking contaminated water, early withdrawal of breast feeding and close intimacy with animals are various factors that can enhance the spread of infection in community. Preventive measures are of great importance in control of spread of infection as there is no specific therapy for cryptosporidiosis.

Community-acquired Clostridium difficile NAP1/027-associated diarrhea in an eighteen month old child

Clostridium difficile infection (CDI), characterized by symptoms varying from diarrhea to life-threatening colitis, is a major complication of antibiotic therapy. Studies suggested that CDI is emerging as an important cause of childhood diarrhea in community and hospital settings. This work is the first report of a documented case of community-acquired CDI by a NAP1 hypervirulent strain in an eighteen month old child from Latin America.

Molecular mechanisms of antibiotic resistance in diarrhoeagenic Escherichia coli isolated from children

Diarrhoeagenic Escherichia coli (DEC) are an important cause of diarrhoea in children and are associated with high antibiotic resistance. However, there are few studies on the molecular mechanisms of resistance in this group of bacteria. The aim of this study was to determine the mechanisms associated with antibiotic resistance in the most common phenotypes of DEC. A total of 369 E. coli strains [commensal strains and DEC from children with (‘DEC-diarrhoea’) or without (‘DEC-control’) diarrhoea] isolated from children aged <1 year in periurban districts of Lima, Peru, were analysed. In total, 154 ampicillin-resistant strains (36 commensals, 33 DEC-control and 85 DEC-diarrhoea) were studied by PCR for the most prevalent resistance mechanisms to ampicillin, trimethoprim/sulfamethoxazole (SXT), tetracycline and chloramphenicol as well as for integrase types 1 and 2. In addition, restriction fragment length polymorphism was performed for SXT-resistant strains. Commensal strains were more frequently resistant to nalidixic acid and ciprofloxacin (68% and 28%, respectively) than DEC strains (23% and 2%, respectively) (P<0.05). DEC-diarrhoea strains were more frequently SXT-resistant (78%) compared with DEC-control strains (65%) and commensal strains (60%) (P<0.05). The most frequent mechanisms of antibiotic resistance in DEC strains were: for β-lactams, blaTEM (31%; 37/118); for SXT, sul2 (48%; 49/103); for tetracycline, tetA (27%; 23/84); and for chloramphenicol, cat (80%; 28/35). The genes sul1 and dfrA1, related to SXT resistance, were more frequent in the DEC-diarrhoea group (41% and 28%, respectively) than in the other two groups (P<0.05). There was a high diversity of resistance genes in DEC, including symptomatic strains.

Epidemiological factors in admissions for diarrhoea in 6 - 60-month-old children admitted to Morogoro Regional Hospital, Tanzania

Objectives. To describe the diarrhoea admissions and the influencing factors in six - 60-month-old children at Morogoro Regional Hospital. Design. A retrospective descriptive study of the type of diarrhoea, patient age, home address, nutritional status, diagnosed infection, month of admission, admission duration and outcome. Setting. A hospital-based study: paediatric admissions at Morogoro Regional Hospital. Subjects. All children aged 6 - 60 months admitted to the infectious diseases ward over the 60-month period from May 2006 to April 2011. Results. A total of 4 988 records were extracted, among which the prevalence of diarrhoea was 2 855 (57.2%). Among the 2 855 children with diarrhoea, the majority (2 536 (88.8%)), were 6 - 24 months old, with peak admissions at 7 months and 12 months. District of residence, season, undernutrition and infection were the factors significantly associated (p<0.001) with the age at which children were admitted with diarrhoea. Conclusions. There were increased numbers of admissions for diarrhoea at the ages of 7 months and 12 months, during the dry season and together with diagnosed infection, particularly malaria. However, further study on causes of childhood diarrhoea, given the identified risk factors, may better explain the epidemiology of diarrhoea in Morogoro.

Diarrhoeagenic Escherichia coli detected by 16-plex PCR in children with and without diarrhoea in Burkina Faso

The importance of diarrhoeagenic Escherichia coli (DEC) in Africa is poorly understood, and is unknown in Burkina Faso. This study investigated the occurrence of five major DEC pathogroups in primary cultures of stool samples from 658 Burkinabe children under 5 years old using 16-plex PCR for virulence-associated genes. At least one DEC pathogroup was detected in 45% of 471 children with diarrhoea and in 29% of 187 children without diarrhoea (p <0.001). More than one DEC pathogroup was detected in 11% of children with and 1% of children without diarrhoea (p <0.00l). Enteroaggregative E. coli was the most common pathogroup in both children with diarrhoea (26%) and children without diarrhoea (21%). Enteropathogenic E. coli and enterotoxigenic E. coli were detected significantly more often in children with diarrhoea (16% and 13%) than in children without diarrhoea (5% and 4%; p <0.001 for both pathogroups). Shiga toxin-producing E. coli and enteroinvasive E. coli were detected only in children with diarrhoea (2% and 1%, respectively). Diarrhoeagenic E. coli, especially enteropathogenic and enterotoxigenic, may be important, unrecognized causes of childhood diarrhoea in Burkina Faso.

Biofilm formation and binding specificities of CFA/I, CFA/II and CS2 adhesions of Enterotoxigenic Escherichia coli and CfaE-R181A mutant

Enterotoxigenic Escherichia coli (ETEC) strains are leading causes of childhood diarrhea in developing countries. Adhesion is the first step in pathogenesis of ETEC infections and ETEC pili designated colonization factor antigens (CFAs) are believed to be important in the biofim formation, colonization and host cell adhesions. As a first step, we have determined the biofilm capability of ETEC expressing various types of pili (CFA/I, CfaE-R181A mutant/CfaE tip mutant, CFA/II and CS2). Further, enzyme-linked immunosorbent assay (ELISA) assay were developed to compare the binding specificity of CFA/I, CFA/II (CS1 - CS3) and CS2 of ETEC, using extracted pili and piliated bacteria. CFA/II strain (E24377a) as well as extracted pili exhibited significantly higher binding both in biofilm and ELISA assays compared to non piliated wild type E24377a, CFA/I and CS2 strains. This indicates that co-expression of two or more CS2 in same strain is more efficient in increasing adherence. Significant decrease in binding specificity of DH5αF'lacI (q)/∆cotD (CS2) strain and MC4100/pEU2124 (CfaE-R181A) mutant strain indicated the important contribution of tip proteins in adherence assays. However, CS2 tip mutant strain (DH5αF'lacI (q)/pEU5881) showed that this specific residue may not be important as adhesions in these strains. In summary, our data suggest that pili, their minor subunits are important for biofilm formation and adherence mechanisms. Overall, the functional reactivity of strains co expressing various antigens, particularly minor subunit antigen observed in this study suggest that fewer antibodies may be required to elicit immunity to ETEC expressing a wider array of related pili.

Phenotypic assay of adherent &lt;em&gt;E. coli&lt;/em&gt; strains using hep-2 cells on diarrheic children in Rivers State of Nigeria

In this paired case-control study of children with diarrhea in Rivers state, the association between HEp-2&#8211;adherent Escherichia coli strains and diarrhea was examined. Escherichia coli isolates from stool specimens of children with diarrhea were matched with controls and tested in HEp-2 cell adherence assay. A total of 266 E. coli strains (2 strains for every test subject) from both 83 children with diarrhea and 50 apparently healthy controls were examined for virulent traits using HEp-2 cells. Statistically significant (P&lt;0.05) adherent strains were obtained from the diarrheic children 18 (21.7%) as against 5(10%) from the control. While EPEC (3.6% vs 0%) and EAEC (10.8% vs 4%) strains were significantly associated with diarrhea (P&lt;0.05), EPEC was isolated only in children &lt;3 years old while EAEC was more distributed on the age ranges studied. There was no significant association of DAEC (7.2% vs 2%) strains isolated from the test subjects and the control group (P&gt;0.05%). High prevalence of parasites were seen on both groups although the diarrheal group had a statistical significant (26.5% vs 16%) prevalence (P&lt;0.05), this showed that intestinal parasites are also important factor in the etiology of diarrhea in this area. The parasites were mostly seen in older children from both groups and this might be attributed to their wandering, playing and eating habits. No mixed infection between parasites, parasite and adherent E. coli or between two adherents E. coli was observed. The adherent isolates showed poor sensitivity to traditional drugs like Ampicillin, Cotrimoxazole and Chloramphenicol, while Cefuroxime and Ceftazidime showed good sensitivity. These data suggest that EAEC may be a pathotype that is increasing in incidence as a cause of diarrhea in children in these areas.Keywords: Adherent E. coli (DEC); Enteropathogenic E. coli (EPEC); Enteroaggregative E. coli (EAEC); Diffusely adherent E. coli (DAEC); Mixed Infections; Intestinal Parasites

Generation of recombinant bacillus Calmette–Guérin and Mycobacterium smegmatis expressing BfpA and intimin as vaccine vectors against enteropathogenic Escherichia coli

Enteropathogenic Escherichia coli (EPEC) is an important cause of diarrhea in children. EPEC adheres to the intestinal epithelium and causes attaching and effacing (A/E) lesions. Recombinant Mycobacterium smegmatis (Smeg) and Mycobacterium bovis BCG strains were constructed to express either BfpA or intimin. The entire bfpA gene and a portion of the intimin gene were amplified by PCR from EPEC genomic DNA and inserted into the pMIP12 vector at the BamHI/KpnI sites. The pMIP_bfpA and pMIP_intimin vectors were introduced separately into Smeg and BCG. Recombinant clones were selected based on kanamycin resistance and designated rSmeg_pMIP_(bfpA or intimin) and rBCG_pMIP_(bfpA or intimin). The expression of bfpA and intimin was detected by Immunoblotting using polyclonal anti-BfpA and anti-intimin antibodies. The immunogenicity of these proteins was assessed in C57BL/6 mice by assaying the feces and serum for the presence of anti-BfpA and anti-intimin IgA and IgG antibodies. TNF-α and INF-γ were produced in vitro by spleen cells from mice immunized with recombinant BfpA, whereas TNF-γ was produced in mice immunized with recombinant intimin. The adhesion of EPEC (E2348/69) to HEp-2 target cells was blocked by IgA or IgG antibodies from mice immunized with recombinant BfpA or intimin but not by antibodies from non-immunized mice. Immunogenic non-infectious vectors containing relevant EPEC virulence genes may be promising vaccine candidates.

Distribution of rotavirus genotypes after vaccine introduction in the Triângulo Mineiro region of Brazil: 4-Year follow-up study

BackgroundRotaviruses are the major cause of diarrhea in children for which a monovalent G1P[8] vaccine has been provided free for all Brazilian infants since March 2006. ObjectivesTo investigate prevalence and genotypes of rotavirus strains causing diarrhea in children in Triângulo Mineiro, Minas Gerais, during 2007–2010, and to assess local vaccine impact. Study designFecal specimens were analyzed for rotavirus detection and characterization by PAGE, RT-PCR and PCR-genotyping assays. ResultsOverall, rotavirus was diagnosed in 12.1% (76/630) cases, accounting for 35.8% of the hospitalizations and 6.5% of outpatient attendance due to diarrhea. A trend in rotavirus disease reduction occurred in both cities (71.8% and 83.4% in Uberaba; 95.3% in Uberlândia) up to 2009, but it reversed in 2010 with increased rotavirus cases in Uberlândia. Short pattern G2P[4] strains were detected in all but three (96%) cases of mixed/P[NT] infections with long electropherotypes. ConclusionsThis 4-year follow-up study showed a reduction in rotavirus-related diarrhea and even skipped a rotavirus season, which is consistent with vaccine mediated protection. The 2007–2010 rotavirus epidemic curve reflected the natural cyclic fluctuation of the single G2P[4] genotype, with sharp reduction of cases in 2008 leading to lack of a rotavirus 2009 season (both cases and hospitalizations) followed by its come back in 2010. Diarrhea cases related to either vaccine serotype/genotype (G1 or P[8]) were not detected. Thus, a new scenario emerged with a single epidemic genotype replacing the cocirculation of great diversity of genotypes, thus far, a hallmark of the epidemiology of rotavirus in Brazil.

Detection of diarrheagenic Escherichia coli by multiplex PCR

Background: Diarrheagenic E.coli (DEC) are an important cause of childhood diarrhea.Identification of DEC strains needs to detect factors that determine the virulence of these organisms. There is not much data regarding the importance of DEC as a cause of diarrhea in children in India.The prevalence of DEC in children belowfive years with and without diarrhea was studied using two multiplex PCR assays. Materials and Methods: Two multiplex polymerase chain reaction assays were used to detect genes of five types of DEC.The targets selected for each category were eae and bfpA (bundle-forming pilus) forEnteropathogenic E.coli (EPEC), hlyA for Enterohemorrhagic E.coli (EHEC), elt and stla for Enterotoxigenic E.coli (ETEC), CVD432 for Enteroaggregative E.coli (EAEC) and ial for Enteroinvasive E.coli (EIEC). Results: In 200 children with diarrhea 52 (26%) DEC infections were found. Among 100 controls 8 (8%) DEC infections were found. EAEC was the most common DEC by multiplex PCR both in cases (26, 13%)and controls (5,5%), followed byEPEC seen in 16% cases and 3% controls. ETEC and EIEC were found in 7 (3.5%) and 3 (1.5%) of the diarrheal cases. EIEC and ETEC were not detected in the control cases. EHEC was not isolated from either the diarrheal or control cases. Conclusion: DEC strains are a significant cause of diarrhea in children. The two Multiplex PCR assays can be used for the detection of DEC in routine diagnostic laboratories. These assays are specific and sensitive for the rapid detection of DEC. EAEC was the most frequent pathotype in the population under study.

Generation of the Recombinant M. smegmatis and M. bovis (BCG) Vaccine with genes of Enteropathogenic E. coli bfpA and intimin. Dias da Silva, W, 1, 3, Vasconcellos, H.L.F. 1,2,3 ; Scaramuzzi, K.1,3; Rodriguez, D.2 ; Nascimento, I.P.2; 1 Laboratório de Imunoquímica, Instituto Butantan São Paulo, SP, Brazi. 2 Laboratório de Biotecnologia, Instituto Butantan São Paulo, SP, Brazil. 3 Departamento de

Abstract Escherichia coli (EPEC) is important cause of diarrhea in children. EPEC adhere the intestinal epithelium causing the attaching and effacing (A/E) lesions. Recombinant M. smegmatis (MS) and BCG were constructed to express bfpA or intimin. Briefly, the whole bfpA gene and the intimin portion were amplified by PCR primers from genomic DNA (EPEC), and inserted into pMIP12 at the BamH I/KpnI sites. The vectors pMIP_bfpA and pMIP _intim were introduced separately into MS and BCG. Recombinants clones were selected based on resistance to kanamycin and named rSmeg_pMIP_(bfpA or intimin) and rBCG_pMIP_(bfpA or intimin). The expression of bfpA and intimin were detected by Western blotting using polyclonal anti-BfpA or anti-Intimin as first antibodies. The immunogenicity of these proteins was assessed in C57BL/6 mice. IgA and IgG antibodies anti-BfpA and anti-Intimin were detected in feces or in serum. TNF-α and INF-γ were produced in vitro by spleen cells from mice immunized with recombinant BfpA and recombinant Intimin. Adhesion of EPEC (E2348/69) on Hep-2 target cells was blocked by IgA or IgG from mice immunized with recombinant BfpA or Intimin, but not by non-immune antibodíes. Immunogenic non-infective vectors containing relevant EPEC virulence genes are promising vaccines.

Systemic Antibody Responses to the Immunodominant p23 Antigen and p23 Polymorphisms in Children with Cryptosporidiosis in Bangladesh

Cryptosporidium is a major cause of diarrhea in children in developing countries. However, there is no vaccine available and little is known about immune responses to protective antigens. We investigated antibody responses to p23, a putative vaccine candidate, in children in Bangladesh with cryptosporidiosis and diarrhea (cases) and uninfected children with diarrhea (controls), and p23 gene polymorphisms in infecting species. Serum IgM, IgG, and IgA responses to p23 were significantly greater in cases than controls after three weeks of follow-up. Cases with acute diarrhea had significantly greater serum IgA and IgM responses than those with persistent diarrhea, which suggested an association with protection from prolonged disease. The p23 sequences were relatively conserved among infecting species and subtype families. Although most children were infected with Cryptosporidium hominis, there was a cross-reactive antibody response to C. parvum antigen. These results support further development of p23 as a vaccine candidate.

Role of enteropathogenic Escherichia coli in paediatric diarrhoeas in South India.

Background:Enteropathogenic Escherichia coli(EPEC) is a major cause of diarrhoea in children below 5 years of age. Serotyping is classical method for identification of EPEC strains. But serotypic markers are rarely sufficient to reliably identify the strains as Escherichia coli. Introduction of PCR methodology which depends on detection of virulence factors has provided a practical and rapid way of detecting diarrhoeagenic Esch.coli. Multiantibiotic resistant EPEC strains are a common phenomenon with world wide extension. Moreover for the selection of appropriate therapy of dirrhoeas, knowledge of local antimicrobial therapy pattern plays an important role.Objectives:To study the role of EPEC in Paediatric diarrhoea by both Serogrouping and Molecular characterisation by PCR and to analyse the antibiotic susceptabililty patterns of EPEC strains in our area.Materials and methods:Prospective study of stool samples collected from children with diarrhoea and without diarrhoea who were below 5 years of age was conducted from May to November 2011. Escherichia.coli isolates were identified by Microscopy, Culture and Biochemical reactions. Among the Escherichia coli isolates, EPEC isolates were identified by Serogrouping. Escherichia coli isolates were also subjected to Molecular characterisation by Multiplex PCR assay and those isolates which showed pathogenic genes were futher serotyped. Antibiotic susceptibility pattern of EPEC isolates was determined by CLSI guidelines.Results:Among the Escherichia coli isolates 36.8% in the diarrhoeal group and none of them from the nondiarrhoeal group were identified as EPEC by serogrouping. 73.3% of the EPEC isolates were below 2 years of age and no much difference in the sex distribution was observed. Mild to moderate dehydration and feccal leuckocytes were seen in 59.9% and 56.6% of isolates respectively. High resistance to Nalidixic acid, Ampicillin, Cotrimoxazole, Ciprofloxacin and Norfloxacin was observed in the diarrhoeal group and resistance to only ampicillin was seen in the nondiarrhoeal group. In the diarrhoeal group 38.8% of Escherichia coli were EAEC and no other diarrhoeagenic Escherichia coli group was found by molecular characterisation. In the nondiarrhoeal Escherichia coli strains, 46.6% showed EAEC genes. EAEC strains in the diarrhoeal group belonged to multiple serotypes, the most common serotype being ONT and in the nondiarrhoeal group, 85.7% were of a single serotype, the most common isolate being O153. Among the Escherichia coli isolates which agglutinated with EPEC polyvalent antisera, 33.3% were positive for Enteroaggregative genes. (Table 1).Conclusion:EPEC is still an important pathogen in paediatric diarrhoeas. O serogrouping can still be relied upon for detection of EPEC. Dehydration is one of the clinical features of EPEC diarrhoea. Fluoroquinolones should only be prescribed in children as second line antibiotics. EAEC are present in classical ‘ O ’ serogroups. Serotype O 153 has an increasing potential for asymptomatic carrier state in children below 5 years of age in our area.

Biofilm formation and binding specificities of CFA/I, CFA/II and CS2 adhesions of enterotoxigenic Escherichia coli and Cfae-R181A mutant

Enterotoxigenic Escherichia coli (ETEC) strains are leading causes of childhood diarrhea in developing countries. Adhesion is the first step in pathogenesis of ETEC infections and ETEC pili designated colonization factor antigens (CFAs) are believed to be important in the biofim formation, colonization and host cell adhesions. As a first step, we have determined the biofilm capability of ETEC expressing various types of pili (CFA/I, CfaE-R181A mutant/CfaE tip mutant, CFA/II and CS2). Further, enzyme-linked immunosorbent assay (ELISA) assay were developed to compare the binding specificity of CFA/I, CFA/II (CS1 - CS3) and CS2 of ETEC, using extracted pili and piliated bacteria. CFA/II strain (E24377a) as well as extracted pili exhibited significantly higher binding both in biofilm and ELISA assays compared to non piliated wild type E24377a, CFA/I and CS2 strains. This indicates that co-expression of two or more CS2 in same strain is more efficient in increasing adherence. Significant decrease in binding specificity of DH5αF’lacIq/∆cotD (CS2) strain and MC4100/pEU2124 (CfaE-R181A) mutant strain indicated the important contribution of tip proteins in adherence assays. However, CS2 tip mutant strain (DH5αF’lacIq/pEU5881) showed that this specific residue may not be important as adhesions in these strains. In summary, our data suggest that pili, their minor subunits are important for biofilm formation and adherence mechanisms. Overall, the functional reactivity of strains co expressing various antigens, particularly minor subunit antigen observed in this study suggest that fewer antibodies may be required to elicit immunity to ETEC expressing a wider array of related pili.

Rotavirus disease burden among children &lt;5 years of age – Santa Rosa, Guatemala, 2007–2009

To assess the burden of rotavirus disease in Guatemala, in view of the recent introduction of a national rotavirus vaccination programme. We examined data from an active, facility-based surveillance system in Santa Rosa, Guatemala, from October 2007 through September 2009 among children <5years of age presenting to the hospital or ambulatory clinics with diarrhoea (≥3 loose stools in 24 h during the last 7 days). Demographic and epidemiological data were collected, and specimens were tested for rotavirus via enzyme immunoassay. Genotyping was performed via reverse transcriptase polymerase chain reaction. We enrolled 347 hospitalized patients <5 years of age with diarrhoea and 1215 from ambulatory clinics. Specimens from 275 (79%) hospitalized children and 662 (54%) from ambulatory visits were tested for rotavirus. Rotavirus accounted for 32% of hospitalizations and 9% of ambulatory visits for diarrhoea, resulting in adjusted annual rates of 36 hospitalizations and 372 ambulatory visits per 10 000 children. Ninety-one per cent of hospitalizations and 81% of ambulatory visits for rotavirus diarrhoea occurred in children <2 years. G1P8 represented 71% and 95% of rotavirus genotypes for 2007-2008 and 2008-2009 rotavirus seasons, respectively. Rotavirus is a major cause of diarrhoea in children <5 years of age in Santa Rosa, Guatemala, highlighting the potential health benefits of vaccination and the need for continued surveillance to assess impact and effectiveness of the rotavirus vaccination programme in Guatemala.