RESUMEN
BACKGROUND: The competence of enteroaggregative Escherichia coli (EAEC) to adhere to the intestinal epithelium of the host is a key role to the colonization and disease development. The virulence genes are crucial for EAEC pathogenicity during adherence, internalization and persistence in the host. The overwhelming majority of antigen encounters in a host occurs on the intestine surface, which is considered a part of innate mucosal immunity. Intestinal epithelial cells (IECs) can be activated by microorganisms and induce an immune response. OBJECTIVE: The present study investigated the interaction of invasive EAEC strains with T84 intestinal epithelial cell line in respect to bacterial invasiveness, persistence and cytokines production. METHODS: We evaluated intracellular persistence of invasive EAEC strains (H92/3, I49/3 and the prototype 042) and production of cytokines by sandwich ELISA in T84 cells upon 24 hours of infection. RESULTS: The survival rates of the prototype 042 was 0.5x103 CFU/mL while survival of I49/3 and H92/3 reached 3.2x103 CFU/mL and 1.4x103 CFU/mL, respectively. Infection with all EAEC strains tested induced significant amounts of IL-8, IL-6 and TNF-α compared to uninfected T84 cells. CONCLUSION: These data showed that infection by invasive EAEC induce a proinflammatory immune response in intestinal epithelial T84 cells.
Asunto(s)
Citocinas/biosíntesis , Células Epiteliales/microbiología , Escherichia coli/patogenicidad , Mucosa Intestinal/microbiología , Adhesinas de Escherichia coli , Adhesión Bacteriana , Preescolar , Citocinas/metabolismo , Diarrea Infantil/microbiología , Células Epiteliales/inmunología , Escherichia coli/fisiología , Humanos , Inmunidad Innata , Lactante , Inflamación/microbiología , Mucosa Intestinal/inmunología , VirulenciaRESUMEN
ABSTRACT BACKGROUND: The competence of enteroaggregative Escherichia coli (EAEC) to adhere to the intestinal epithelium of the host is a key role to the colonization and disease development. The virulence genes are crucial for EAEC pathogenicity during adherence, internalization and persistence in the host. The overwhelming majority of antigen encounters in a host occurs on the intestine surface, which is considered a part of innate mucosal immunity. Intestinal epithelial cells (IECs) can be activated by microorganisms and induce an immune response. OBJECTIVE: The present study investigated the interaction of invasive EAEC strains with T84 intestinal epithelial cell line in respect to bacterial invasiveness, persistence and cytokines production. METHODS: We evaluated intracellular persistence of invasive EAEC strains (H92/3, I49/3 and the prototype 042) and production of cytokines by sandwich ELISA in T84 cells upon 24 hours of infection. RESULTS: The survival rates of the prototype 042 was 0.5x103 CFU/mL while survival of I49/3 and H92/3 reached 3.2x103 CFU/mL and 1.4x103 CFU/mL, respectively. Infection with all EAEC strains tested induced significant amounts of IL-8, IL-6 and TNF-α compared to uninfected T84 cells. CONCLUSION: These data showed that infection by invasive EAEC induce a proinflammatory immune response in intestinal epithelial T84 cells.
RESUMO CONTEXTO: A competência de Escherichia coli enteroagregativa (EAEC) para aderir ao epitélio intestinal do hospedeiro é um papel fundamental para a colonização e o desenvolvimento da doença. Os genes de virulência são cruciais para a patogenicidade de EAEC durante a aderência, a internalização e a persistência no hospedeiro. A grande maioria dos encontros de antígenos em um hospedeiro ocorre na superfície do intestino, que é considerada parte da imunidade inata da mucosa. As células epiteliais intestinais (IECs) podem ser ativadas por micro-organismos e induzir uma resposta imune. OBJETIVO: O presente estudo investigou a interação de cepas invasoras de EAEC com a linhagem celular epitelial intestinal T84 em relação a invasão bacteriana, a persistência e a produção de citocinas. MÉTODOS: Avaliamos a persistência intracelular de cepas invasoras de EAEC (H92/3, I49/3 e o protótipo 042) e a produção de citocinas por ELISA "sanduíche" em células T84 após 24 horas de infecção. RESULTADOS: As taxas de sobrevivência da cepa protótipo 042 foi de 0,5x103 UFC/mL, enquanto a sobrevivência de I49/3 e H92/3 atingiu 3,2x103 UFC/mL e 1,4x103 UFC/mL, respectivamente. A infecção com todas as cepas EAEC testadas induziu quantidades significativas de IL-8, IL-6 e TNF-α em comparação com células T84 não infectadas. CONCLUSÃO: Estes dados mostraram que a infecção por EAEC invasoras induzem uma resposta imune pró-inflamatória em células epiteliais intestinais T84.
Asunto(s)
Humanos , Lactante , Preescolar , Citocinas/biosíntesis , Células Epiteliales/microbiología , Escherichia coli/patogenicidad , Mucosa Intestinal/microbiología , Virulencia , Adhesión Bacteriana , Citocinas/metabolismo , Adhesinas de Escherichia coli , Diarrea Infantil/microbiología , Células Epiteliales/inmunología , Escherichia coli/fisiología , Inmunidad Innata , Inflamación/microbiología , Mucosa Intestinal/inmunologíaRESUMEN
Understanding how the gut microbiota is affected by diarrhea episodes may help explain alterations in intestinal function among children in low-income settings. This study examined the composition of the gut microbiome of Nicaraguan children both during diarrhea episodes and while free of diarrhea for at least 2 months. Relative abundances of bacterial taxa, phylogenetic diversity, and species richness were determined by 16S amplicon sequencing and compared between paired diarrhea and recovery samples. A total of 66 stools were provided by 25 children enrolled in a 1-year cohort study of diarrhea etiologies. Children in our cohort had a mean age of 21.9 months; 64% were breast-fed, and 10% had received an antibiotic during the diarrhea episode. Overall, phylogenetic diversity and species richness did not differ significantly between diarrhea and recovery stools. However, of children who had a bacterial enteropathogen detected in any diarrhea stool, none experienced an increase in phylogenetic diversity in recovery, whereas of those in whom no bacterial enteropathogens were detected in their diarrhea stool(s), 59% experienced an increase in phylogenetic diversity in recovery (P = 0.008). This preliminary study suggests that recovery of the gut microbiota after a diarrhea episode may take longer time than previously thought and may be pathogen specific.
Asunto(s)
Diarrea Infantil/microbiología , Microbioma Gastrointestinal , ADN Ribosómico/genética , Diarrea/microbiología , Heces/microbiología , Femenino , Microbioma Gastrointestinal/genética , Humanos , Lactante , Masculino , Nicaragua/epidemiología , FilogeniaRESUMEN
Diarrhea remains the third leading cause of death in children under five years, despite recent advances in the management and prevention of this disease. It is caused by multiple pathogens, however, the prevalence of each varies by age group, geographical area and the scenario where cases (community vs hospital) are recorded. The most relevant pathogens in public health are those associated with the highest burden of disease, severity, complications and mortality. In our country, norovirus, Campylobacter and diarrheagenic E. coli are the most prevalent pathogens at the community level in children. In this paper we review the local epidemiology and potential areas of development in five selected pathogens: rotavirus, norovirus, Shiga toxin-producing E. coli (STEC), Shigella and Salmonella. Of these, rotavirus is the most important in the pediatric population and the main agent responsible for child mortality from diarrhea. The introduction of rotavirus vaccination in Peru will have a significant impact on disease burden and mortality from diarrhea. However, surveillance studies are needed to determine the impact of vaccination and changes in the epidemiology of diarrhea in Peru following the introduction of new vaccines, as well as antibiotic resistance surveillance of clinical relevant bacteria.
Asunto(s)
Infecciones por Caliciviridae/epidemiología , Disentería Bacilar/epidemiología , Infecciones por Escherichia coli/epidemiología , Gastroenteritis/epidemiología , Gastroenteritis/microbiología , Norovirus , Salud Pública , Infecciones por Rotavirus/epidemiología , Infecciones por Salmonella/epidemiología , Escherichia coli Shiga-Toxigénica , Diarrea Infantil/epidemiología , Diarrea Infantil/microbiología , Humanos , Lactante , Perú , PrevalenciaRESUMEN
Conventionally, in Escherichia coli, phylogenetic groups A and B1 are associated with commensal strains while B2 and D are associated with extraintestinal strains. The aim of this study was to evaluate diarrheagenic (DEC) and commensal E. coli phylogeny and its association with antibiotic resistance and clinical characteristics of the diarrheal episode. Phylogenetic groups and antibiotic resistance of 369 E. coli strains (commensal strains and DEC from children with or without diarrhea) isolated from Peruvian children <1 year of age were determined by a Clermont triplex PCR and Kirby-Bauer method, respectively. The distribution of the 369 E. coli strains among the 4 phylogenetic groups was A (40%), D (31%), B1 (21%), and B2 (8%). DEC-control strains were more associated with group A while DEC-diarrhea strains were more associated with group D (P < 0.05). There was a tendency (P = 0.06) for higher proportion of persistent diarrhea (≥ 14 days) among severe groups (B2 and D) in comparison with nonsevere groups (A and B1). Strains belonging to group D presented significantly higher percentages of multidrug resistance than the rest of the groups (P > 0.01). In summary, DEC-diarrhea strains were more associated with group D than strains from healthy controls.
Asunto(s)
Diarrea Infantil/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/clasificación , Estudios de Casos y Controles , Diarrea Infantil/tratamiento farmacológico , Farmacorresistencia Microbiana/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Femenino , Humanos , Lactante , Masculino , Perú , Filogenia , Factores de Tiempo , Virulencia/genéticaRESUMEN
OBJECTIVES: To determine the effect of bovine lactoferrin (BLF) in the formation of biofilms in clinical enteroaggregative Escherichia coli (EAEC) strains and whether this effect is independent of iron. MATERIALS AND METHODS: Two methods were used: (a) qualitative, by direct observation of optical microscopy, and (b) quantitative readings of the absorbance values using ELISA reader in the presence of bLf in concentrations of 0.01 mg mL and 1 mg/mL, with and without iron and no bLf (control). Analysis occurred in 122 strains of EAEC (60 strains from children with diarrhea and 62 healthy children) previously collected in a previous study of passive surveillance of diarrhea in the Southern Cone Lima. 31 strains of the same method were used for the qualitative study. RESULTS: (A) Qualitative method: 31 strains were evaluated with and without iron. Without iron biofi formation was 77% (24/31) in the control group versus 58% (14/31) with bLf of 0.01 mg/mL and 4% (1/31) with 1 mg/ml. Iron biofilm formation was 90% (28/31) in the control group versus 55% (17/31) with bLf of 0.01 mg/mL and 4% (1/31) with 1 mg/mL. (B) Quantitative method: without iron absorbance measured at OD 560 nm of the control group was 0.7 ± 0.5 versus 0.4 ± 0.3 with bLf 0.01 mg/mL and 0.3 ± 0.2 with bLf of 1 mg/mL (p<0.0001). This decrease in the presence of bLf included iron. CONCLUSIONS: bLf tends to decrease the formation of biofilms, showing an inhibitory effect in clinical isolates of EAEC; this effect is not iron-dependent.
Asunto(s)
Biopelículas/efectos de los fármacos , Diarrea Infantil/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Lactoferrina/farmacología , Fragmentos de Péptidos/farmacología , Humanos , LactanteAsunto(s)
Diarrea Infantil/historia , Gastroenteritis/historia , Intestinos/microbiología , Infecciones Bacterianas/historia , Niño , Diarrea Infantil/microbiología , Diarrea Infantil/parasitología , Diarrea Infantil/virología , Gastroenteritis/microbiología , Gastroenteritis/parasitología , Gastroenteritis/virología , Historia del Siglo XX , Humanos , Lactante , Recién Nacido , Parasitosis Intestinales/historia , Puerto Rico , Virosis/historiaRESUMEN
Complementary foods based on cow's milk or gruels consumed by children in developing countries are often contaminated by bacteria during preparation, and ambient temperature rapidly increases microbial load. Thus infant formula or other weaning foods may cause diarrhea in young infants accounting for 25-33% of all deaths <5 years globally. Environmental chemicals such as metals (As, Pb, Cu) and nitrates can cause vomiting/diarrhea. Polychlorinated biphenyls derived from plastics, present in formula and/or breast milk, are endocrine disruptors (the potential threats are not fully quantifiable). The prevailing view is that benefits from breastfeeding outweigh potential risks.
Asunto(s)
Países en Desarrollo , Contaminación de Alimentos , Alimentos Infantiles/análisis , Alimentos Infantiles/microbiología , Fórmulas Infantiles/química , Leche Humana , Animales , Bacterias/crecimiento & desarrollo , Infecciones Bacterianas/prevención & control , Bovinos , Preescolar , Diarrea/microbiología , Diarrea Infantil/microbiología , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos , Humanos , Higiene , Lactante , Recién Nacido , Leche/microbiología , Leche Humana/química , TemperaturaRESUMEN
AIMS: To investigate the distribution of the genes that encode enterotoxins and the colonization factors (CF) types as well as the antibiotic susceptibility profile of enterotoxigenic Escherichia coli (ETEC) isolated from children from the Brazilian Northeast. METHODS AND RESULTS: We conducted a 3·5-year prospective study that involved 250 children with and 150 without diarrhoea, aged 1-60 months, from low-income families in Teresina/Brazilian Northeast. All samples were assayed for E. coli, enterotoxin and CF genes and antimicrobial susceptibility by microbiological methods and PCR. ETEC strains were isolated from 9·2% children with and 4·0% without diarrhoea. Infection was more common in children aged 6-24 months in rainy months. elt⺠/CFA/IV⺠and elt⺠/CS14⺠were the most frequent genotypes. Susceptibility to nalidixic acid, ciprofloxacin and gentamicin and resistance to ampicillin, cephalothin and sulfamethoxazole-trimethoprim were common. CONCLUSIONS: elt âºisolates and ETEC strains harbouring genes encoding CFA/IV and CS/14 were the most common ETEC found in Brazilian Northeast. SIGNIFICANCE AND IMPACT OF THE STUDY: Our data, the first generated for north-eastern Brazilian children, may be important for the development of an effective vaccine and for facilitation of an empirical choice of antibiotic treatment or prophylaxis for traveller's diarrhoea in the area studied.
Asunto(s)
Diarrea/microbiología , Escherichia coli Enterotoxigénica/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Toxinas Bacterianas/genética , Brasil , Preescolar , Diarrea/tratamiento farmacológico , Diarrea Infantil/tratamiento farmacológico , Diarrea Infantil/microbiología , Escherichia coli Enterotoxigénica/efectos de los fármacos , Escherichia coli Enterotoxigénica/genética , Escherichia coli Enterotoxigénica/patogenicidad , Infecciones por Escherichia coli/tratamiento farmacológico , Proteínas de Escherichia coli/genética , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Factores de Virulencia/genéticaRESUMEN
OBJETIVO: Avaliar interações de amostras de Escherichia coli enteroagregativa com tecido intestinal humano, a fim de documentar potenciais alterações em diferentes regiões do trato digestivo. MÉTODOS: Amostras de Escherichia coli enteroagregativa isoladas das fezes de crianças com diarreia persistente e a amostra protótipo 042, isolada de uma criança com diarreia em Lima, no Peru (controle positivo), foram analisadas por microscopia óptica de luz após semeadura em cultura de orgão in vitro de fragmentos de mucosa ileal e colônica. Foram analisadas as interações entre as diferentes cepas de Escherichia coli enteroagregativa e as mucosas ileal e colônica. RESULTADOS: A análise por microscopia óptica de luz indicou associação destes micro-organismos com o epitélio, provocando alterações. As cepas estudadas aderiram a ambas as regiões avaliadas (intestino delgado distal e grosso) e causaram alterações, especialmente naquelas áreas onde interagiram diretamente com o epitélio. No íleo, algumas regiões mostraram internalização secundária. CONCLUSÕES: Esses agentes podem causar diarreia persistente por meio de alterações no intestino delgado, no qual ocorrem as funções digestivo-absortivas. As lesões inflamatórias descritas na mucosa colônica poderiam explicar a colite mostrada em algumas crianças infectadas por Escherichia coli enteroagregativa.
OBJECTIVE: To examine the interactions of Enteroaggregative Escherichia coli strains with small and large intestinal mucosa, in order to detect potential alterations in both regions of the digestive tract. METHODS: Enteroaggregative Escherichia coli strains, isolated from stools of infants with persistent diarrhea and the prototype strain 042 (O44:H18), isolated from a child with diarrhea in Lima, Peru (positive control), were analised by light microscopy after in vitro organ culture assay of ileal and colonic mucosa. The interactions between the different enteroaggregative Escherichia coli strains and the ileal and colonic mucosa were analysed. RESULTS: Light microscopy analysis suggested an association of enteroaggregative Escherichia coli strains with the epithelium, inducing alterations. These bacteria adhered to both small and large bowel mucosa. The enteroaggregative Escherichia coli strains induced alterations in those areas where they were directly interacting with the epithelium. In the ileum, some areas showed a secondary internalization. CONCLUSIONS: The enteroaggregative Escherichia coli strains could cause persistent diarrhea inducing alterations in the small intestinal structures, where the digestive-absorptive functions take place. Inflammatory lesions observed in colons could justify the colitis described in some children infected by enteroaggregative Escherichia coli.
OBJETIVO: Evaluar interacciones de muestras de Escherichia coli enteroagregativa (EAEC) con tejido intestinal humano, a fin de documentar potenciales alteraciones en distintas regiones del tracto digestivo (intestino delgado distal e intestino grueso) y definir, con eso, su rol en la persistencia del proceso diarreico. MÉTODOS: Muestras de EAEC aislada de las heces de niños con diarrea persistente y la muestra prototipo 042, aislada de un niño con diarrea en Lima, Perú (control positivo) fueron analizadas por microscopía óptica de luz (ML) después de siembra en cultura de órgano in vitro de fragmentos de mucosa ileal y del colon. Fueron analizadas las interacciones entra las distintas cepas de EAEC y las mucosas ileal y del colon. RESULTADOS: El análisis por ML indicó asociación de estos microorganismos con el epitelio, provocando alteraciones. Las cepas estudiadas adhirieron a ambas regiones evaluadas: intestino delgado distal y grueso y causaron alteraciones, especialmente en aquellas áreas donde interactuaron directamente con el epitelio. En el íleo, algunas regiones mostraron internalización secundaria. CONCLUSIÓN: Estos agentes pueden causar diarrea persistente mediante alteraciones en el intestino delgado, donde ocurren las funciones digestivo-absortibas. Las lesiones inflamatorias descritas en la mucosa del colon podrían explicar la colitis descrita en algunos niños infectados por EAEC.
Asunto(s)
Humanos , Lactante , Diarrea Infantil/etiología , Diarrea Infantil/microbiología , Escherichia coli/patogenicidad , Escherichia coli/ultraestructura , MicroscopíaRESUMEN
Para establecer la prevalencia de cepas de E. coli diarreogénicas (ECD) asociadas a casos de diarrea aguda infantil en Cumaná, Venezuela; se tomaron muestras de heces de 200 niños con enfermedad diarreica aguda, menores de 5 años, y de 30 niños sanos incluidos como control. El aislamiento e identificación bacteriana se realizó por coprocultivos y pruebas bioquímicas convencionales. Para determinar la presencia de los genes de patogenicidad de cada tipo de ECD se usó la técnica de reacción en cadena de la polimerasa (PCR), determinando los genes eae y bfp (ECEP), st y lt (ECET), ipaH y virF (ECEI), Stx1/Stx2 (ECST), aafII (ECEA) y daaE (ECAD). Se realizaron 169 aislamientos de E. coli, de las cuales se determinó por PCR que el 10,65% fueron positivas para ECEP (1,18% típicas; 9,47% atípicas); ECET (5,91%); ECEA (1,78%); ECEI (0,59%). No se observaron diferencias estadísticas significativas en cuanto a la frecuencia de cada patotipo en relación a la edad, pero si en relación con el sexo (p< 0,05). Las características clínicas más relevantes fueron: fiebre, vómito y dolor abdominal y el mayor porcentaje de los niños afectados estuvo en las clases obrera y marginal. Estos resultados muestran que las cepas de ECD, son agentes etiológicos importantes en la enfermedad diarreica aguda infecciosa en la población infantil de Cumaná.
To establish the prevalence of strains of diarrheagenic Escherichia coli (DEC) associated to acute diarrhea in childrem of Cumaná, Venezuela, stool samples were taken from 200 children aged < 5 years with acute diarrheal disease, and from 30 healthy children used as control. Isolation and bacterial identification was performed by conventional biochemical tests and stool cultures. The presence of pathogenic genes of each type of DEC was investigated by the technique of polymerase chain reaction (PCR), determining the genes eae and bfp (EPEC), st and lt (ETEC), ipaH and virF (EIEC) Stx1/Stx2 (STEC), aafII (EAEC) and daaE (ADEC). From 169 E. coli, isolates we determined by PCR 10.65% positive for EPEC (1.18% typical, 9.47% atypical); ETEC (5.91%); EAEC (1.78 %), EIEC (0.59%). There were no statistically significant differences regarding the frequency of each pathotype in relation to age, but it did occur when related to the sex (p<0.05). The most relevant clinical features were: fever, vomiting and abdominal pain and the greatest percentage of children affected were of the working and marginal classes. These results shown that the strains of DEC are important etiological agents in acute infectious diarrhea in children of Cumaná.
Asunto(s)
Preescolar , Femenino , Humanos , Lactante , Masculino , Diarrea/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/aislamiento & purificación , Enfermedad Aguda , Lactancia Materna , Diarrea Infantil/complicaciones , Diarrea Infantil/epidemiología , Diarrea Infantil/microbiología , Diarrea/complicaciones , Diarrea/epidemiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Infecciones por Escherichia coli/epidemiología , Escherichia coli/clasificación , Escherichia coli/genética , Escherichia coli/patogenicidad , Heces/microbiología , Genes Bacterianos , Genotipo , Hospitales Universitarios/estadística & datos numéricos , Alimentos Infantiles , Prevalencia , Factores Socioeconómicos , Especificidad de la Especie , Venezuela/epidemiologíaRESUMEN
INTRODUCTION: The identification of EPEC in clinical laboratories is based on the determination of the serotypes by agglutination with O and H antiserum. Currently the proper diagnosis of EPEC should be done by the identification of the intimin gen (eaeA) by PCR. OBJECTIVES: To compare the diagnosis of EPEC by serotyping and by PCR. MATERIALS AND METHODS: We collected EPEC strains, identify by their O antigen, from 4 clinical laboratories in Lima from diarrheal samples in children less than 5 years of age. In those strains we have searched for virulence genes by a real time multiplex PCR for the diarrheagenic E. coli. RESULTS: We collected 113 strains; 82% from children less than 2 years of age. Only 15 strains (13.3%) had the intimin gene and therefore a confirmatory diagnosis of EPEC. In addition we found 3 enterotoxigenic (ETEC), 3 shiga toxin-producing (STEC), 1 enteroagreggative (EAEC) and 1 enteroinvasive (EIEC) strains. CONCLUSIONS: PCR should be use for the proper identification of EPEC. However, molecular methods are still not easily available in clinical laboratories worldwide.
Asunto(s)
Adhesinas Bacterianas/genética , Pruebas de Aglutinación , Diarrea Infantil/diagnóstico , Escherichia coli Enteropatógena/aislamiento & purificación , Infecciones por Escherichia coli/diagnóstico , Proteínas de Escherichia coli/genética , Reacción en Cadena de la Polimerasa , Antígenos Bacterianos/sangre , Preescolar , ADN Bacteriano/aislamiento & purificación , Diarrea/diagnóstico , Diarrea/microbiología , Diarrea Infantil/microbiología , Escherichia coli Enteropatógena/genética , Escherichia coli Enteropatógena/inmunología , Escherichia coli Enteropatógena/patogenicidad , Escherichia coli/clasificación , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Humanos , Lactante , Antígenos O/sangre , Estudios Prospectivos , Estudios Retrospectivos , Escherichia coli Shiga-Toxigénica/genética , Especificidad de la Especie , Virulencia/genéticaRESUMEN
In the province of Salta, in the Northwest region of Argentina, almost two-thirds of the population live in absolute poverty, and diseases associated with poverty are rampant. Almost 12% of the total population of the province are children below 5 years of age; almost half of these infants are living in situations where the basic necessities are not available. Primitive sanitary conditions, including widespread contamination of available water supplies with pathogens, contribute to a major public health problem. Infant mortality was 17% higher for Salta than for Argentina as a whole in 2001. A major cause of death for these children is infectious disease, especially respiratory and intestinal diseases. In Salta, more than half of the total population of infants is affected by diarrhoea annually. The infectious pathogens are diverse: bacteria (predominantly in spring and summer), viruses (especially in the winter) and parasites (endemic in some situations). This paper evaluates current methods used to test for the presence of pathogens in drinking water; discusses why these methods are less than adequate; documents an episode of contamination in a local water supply source; and suggests appropriate methods that can be used to better address this major public health issue effectively.
Asunto(s)
Diarrea Infantil/epidemiología , Microbiología del Agua , Contaminación del Agua/efectos adversos , Abastecimiento de Agua/normas , Argentina/epidemiología , Preescolar , Diarrea Infantil/microbiología , Diarrea Infantil/mortalidad , Humanos , Incidencia , Lactante , Mortalidad Infantil , Recién Nacido , Áreas de Pobreza , Contaminantes del Agua/efectos adversos , Contaminantes del Agua/análisis , Contaminación del Agua/estadística & datos numéricosRESUMEN
UNLABELLED: A case of neonatal rectal prolapse during Shigella diarrhea is described. A 10 days neonate exclusively breast fed, whose 2 years old brother has had the same process 2 weeks ago. Medical treatment with intravenous ceftriaxone resolved rectal prolapse in 48 hours. Stool cultures showed the presence of Shigella flexneri II resistant to amoxicillin; blood and cerebrospinal fluid, cultures were negative. CONCLUSION: Rectal prolapse is an uncommon complication seen in infants with Shigella diarrhea. It has been described in older children, but never before in neonates.
Asunto(s)
Diarrea Infantil/complicaciones , Diarrea Infantil/microbiología , Disentería Bacilar/complicaciones , Prolapso Rectal/etiología , Shigella flexneri , Humanos , Recién Nacido , MasculinoRESUMEN
To establish the prevalence of strains of diarrheagenic Escherichia coli (DEC) associated to acute diarrhea in children of Cumaná, Venezuela, stool samples were taken from 200 children aged < 5 years with acute diarrheal disease, and from 30 healthy children used as control. Isolation and bacterial identification was performed by conventional biochemical tests and stool cultures. The presence of pathogenic genes of each type of DEC was investigated by the technique of polymerase chain reaction (PCR), determining the genes eae and bfp (EPEC), st and lt (ETEC), ipaH and virF (EIEC) Stx1/Stx2 (STEC), aafII (EAEC) and daaE (ADEC). From 169 E. coli, isolates we determined by PCR 10.65% positive for EPEC (1.18% "typical", 9.47% "atypical"); ETEC (5.91%); EAEC (1.78 %), EIEC (0.59%). There were no statistically significant differences regarding the frequency of each "pathotype" in relation to age, but it did occur when related to the sex (p<0.05). The most relevant clinical features were: fever, vomiting and abdominal pain and the greatest percentage of children affected were of the working and marginal classes. These results shown that the strains of DEC are important etiological agents in acute infectious diarrhea in children of Cumaná.
Asunto(s)
Diarrea/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/aislamiento & purificación , Enfermedad Aguda , Lactancia Materna , Preescolar , Diarrea/complicaciones , Diarrea/epidemiología , Diarrea Infantil/complicaciones , Diarrea Infantil/epidemiología , Diarrea Infantil/microbiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Escherichia coli/clasificación , Escherichia coli/genética , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/epidemiología , Heces/microbiología , Femenino , Genes Bacterianos , Genotipo , Hospitales Universitarios/estadística & datos numéricos , Humanos , Lactante , Alimentos Infantiles , Masculino , Prevalencia , Factores Socioeconómicos , Especificidad de la Especie , Venezuela/epidemiologíaRESUMEN
In a study conducted in João Pessoa, northeast of Brazil, 2344 Escherichia coli isolated from 290 infants with diarrhea and 290 healthy matched controls were analyzed for virulence traits. Enteroaggregative E. coli (EAEC) was the most prevalent pathogen associated to acute diarrhea. Based on the results of colony blot hybridization, serotyping, and HEp-2 cell adherence assays, strains were separated in categories as typical enteropathogenic E. coli (EPEC) (1.7%), atypical EPEC (a-EPEC) (9.3%), EAEC (25%), enterotoxigenic E. coli (10%), and enteroinvasive E. coli (EIEC) (1.4%). No enterohemorrhagic E. coli strains were isolated. Other enteropathogens were found, including Salmonella (7.9%), Shigella spp. (4.1%), thermophilic Campylobacter spp. (2.4%), Giardia lamblia (9.3%), and Entamoeba histolytica (5.8%). All enteropathogens were associated with diarrhea (P < 0.01). However, the association was lower for EPEC and EIEC (P < 0.03). Different pathogens associated with diarrhea may have been changing in Brazil where EAEC and a-EPEC seem to be the most prevalent pathogens among them.
Asunto(s)
Diarrea Infantil/microbiología , Escherichia coli Enteropatógena/clasificación , Infecciones por Escherichia coli/microbiología , Brasil/epidemiología , Estudios de Casos y Controles , Adhesión Celular , Línea Celular Tumoral , Distribución de Chi-Cuadrado , Diarrea Infantil/epidemiología , Escherichia coli Enteropatógena/genética , Escherichia coli/clasificación , Escherichia coli/genética , Infecciones por Escherichia coli/epidemiología , Heces/microbiología , Bacterias Gramnegativas/clasificación , Bacterias Gramnegativas/genética , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Lactante , Prevalencia , Serotipificación , VirulenciaRESUMEN
BACKGROUND: Diarrheagenic Escherichia coli strains are being recognized as important pediatric enteropathogens worldwide. However, it is unclear whether there are differences in age-related susceptibility to specific strains, especially among infants. METHODS: We conducted a passive surveillance cohort study of diarrhea that involved 1034 children aged 2-12 months in Lima, Peru. Control stool samples were collected from randomly selected children without diarrhea. All samples were analyzed for common enteric pathogens and for diarrheagenic E. coli with use of multiplex real-time polymerase chain reaction. RESULTS: The most frequently isolated pathogens in 1065 diarrheal episodes were diarrheagenic E. coli strains (31%), including enteroaggregative (15.1%) and enteropathogenic E. coli (7.6%). Diarrheagenic E. coli, Campylobacter species, and rotavirus were more frequently isolated from infants aged >or=6 months. Among older infants, diffusely adherent E. coli and enterotoxigenic E. coli were more frequently isolated from diarrheal samples than from control samples (P <.05). Children aged >or=6 months who were infected with enterotoxigenic E. coli had a 4.56-fold increased risk of diarrhea (95% confidence interval, 1.20-17.28), compared with younger children. Persistent diarrhea was more common in infants aged <6 months (13.5% vs 3.6%; P <.001). Among children with diarrheagenic E. coli-positive samples, coinfections with other pathogens were more common in children with diarrhea than in control children (40.1% vs 15.6%; P <.001). CONCLUSIONS: Diarrheagenic E. coli strains were more frequently isolated in samples from older infants. In this setting with high frequency of pathogen exposure and high frequency of breastfeeding, we hypothesize that the major age-related differences result from decreased exposure to milk-related protective factors and from increased exposure to contaminated food and water.
Asunto(s)
Diarrea Infantil/epidemiología , Diarrea Infantil/microbiología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/fisiología , Factores de Edad , Escherichia coli/genética , Femenino , Humanos , Lactante , Masculino , Perú/epidemiología , Vigilancia de la Población , PrevalenciaRESUMEN
In a prospective passive diarrhea surveillance cohort study of 1,034 infants of low socioeconomic communities in Lima, Peru, we determined the prevalence and antimicrobial drug susceptibility of the diarrheagenic Escherichia coli . The prevalence of diarrheagenic E. coli was 29% (161 of 557) in children with gastroenteritis and 30% (58 of 195) in the control group without diarrhea. The most common E. coli pathogens in diarrhea were enteroaggregative E. coli (EAEC) (14%), enteropathogenic E. coli (EPEC) (7%), diffusely adherent E. coli (DAEC) (4%), and enterotoxigenic E. coli (ETEC) (4%). Diarrheagenic E. coli as a group exhibited high levels of antimicrobial drug resistance in diarrheal cases to ampicillin (85%), cotrimoxazole (79%), tetracycline (65%), and nalidixic acid (28%). Among individual E. coli groups in patients with diarrhea, DAEC and EAEC exhibited significant higher frequencies of resistance to ampicillin, cotrimoxazole, tetracycline and nalidixic acid than EPEC and ETEC. Antimicrobial drug resistance to ampicillin and cotrimoxazole were more frequent in E. coli isolated from diarrheal samples than controls, which reflected greater antibiotic exposure in patients with gastroenteritis.