Multidrug resistance and risk factors associated with community-acquired urinary tract infections caused by Escherichia coli in Venezuela / Multirresistencia a medicamentos y factores de riesgo asociados con infecciones urinarias por Escherichia coli adquiridas en la comunidad, Venezuela

Abstract Introduction: The treatment of urinary tract infections has become more challenging due to the increasing frequency of multidrug-resistant Escherichia coli in human populations. Objective: To characterize multidrug-resistant E. coli isolates causing community-acquired urinary tract infections in Cumaná, Venezuela, and associate possible risk factors for infection by extended-spectrum beta-lactamases (ESBL)-producing isolates. Materials and methods: We included all the patients with urinary tract infections attending the urology outpatient consultation and emergency unit in the Hospital de Cumaná, Estado Sucre, Venezuela, from January through June, 2014. blaTEM, blaSHV and blaCTX-M genes detection was carried out by PCR. Results: We found a high prevalence of multidrug-resistant E. coli (25.2%) with 20.4% of the isolates producing ESBL. The ESBL-producing isolates showed a high frequency (66.7%) of simultaneous resistance to trimethoprim-sulphamethoxazole, fluoroquinolones and aminoglycosides compared to non-producing isolates (2.4%). Of the resistant isolates, 65.4% carried the blaTEM gene, 34.6% the blaCTX-M and 23.1% the blaSHV. The blaCTX-M genes detected belonged to the CTX-M-1 and CTX-M-2 groups. Plasmid transfer was demonstrated by in vitro conjugation in 17 of the 26 ESBL-producing isolates. All three genes detected were transferred to the transconjugants. Age over 60 years, complicated urinary tract infections and previous use of a catheter predisposed patients to infection by ESBL-producing E. coli. Conclusions: The high frequency of multidrug-resistant ESBL-producing isolates should alert the regional health authorities to take measures to reduce the risk of outbreaks caused by these types of bacteria in the community.

Resumen Introducción. El tratamiento de las infecciones urinarias constituye un reto creciente por el aumento de Escherichia coli proveniente de la comunidad multirresistente a los medicamentos. Objetivo. Caracterizar aislamientos de E. coli multirresistente causantes de infecciones urinarias adquiridas en la comunidad en Cumaná, Venezuela, y detectar los posibles riesgos de infección por aislamientos productores de betalactamasas de espectro extendido (BLEE). Materiales y métodos. Se incluyeron todos los pacientes atendidos en la consulta externa de urología y en urgencias del Hospital de Cumaná entre enero y junio de 2014 y que evidenciaban infecciones urinarias. La detección de los genes blaTEM, blaSHV y blaCTX-M se hizo mediante la reacción en cadena de la polimerasa (PCR). Resultados. Se encontró una alta prevalencia de E. coli multirresistente a los medicamentos (25,2 %), con 20,4 % de aislamientos productores de BLEE y una gran frecuencia de resistencia simultánea a trimetoprim-sulfametoxazol, fluoroquinolonas y aminoglucósidos (66,7 %) comparados con los no productores (2,4 %). En el 65,4 % de los aislamientos resistentes, se encontró el gen blaTEM; en 34,6 %, el blaCTX-M, y en 23,1 %, el blaSHV. Los genes blaCTX-M detectados pertenecían a los grupos CTX-M-1 y CTX-M-2. Se demostró la transferencia in vitro de plásmidos por conjugación en 17 de los 26 aislamientos productores de BLEE. Los tres tipos de genes detectados se transfirieron a los transconjugantes. La edad mayor de 60 años, las infecciones urinarias con complicaciones y el uso previo de catéter, predispusieron a la infección por cepas de E. coli productoras de BLEE. Conclusiones. La gran frecuencia de aislamientos multirresistentes productores de BLEE debería alertar a las autoridades sanitarias para tomar medidas que reduzcan el riesgo de epidemias causadas por este tipo de bacterias en la comunidad.

Chronic prostatitis alters the prostatic microenvironment and accelerates preneoplastic lesions in C57BL/6 mice

BACKGROUND: Chronic prostatitis has been supposed to be associated with preneoplastic lesions and cancer development. The objective of this study was to examine how chronic inflammation results in a prostatic microenvironment and gene mutation in C57BL/6 mice. METHODS: Immune and bacterial prostatitis mouse models were created through abdominal subcutaneous injection of rat prostate extract protein immunization (EAP group) or transurethral instillation of uropathogenic E. coli 1677 (E. coli group). Prostate histology, serum cytokine level, and genome-wide exome (GWE) sequences were examined 1, 3, and 6 months after immunization or injection. RESULT: In the EAP and E. coli groups, immune cell infiltrations were observed in the first and last months of the entire experiment. After 3 months, obvious proliferative inflammatory atrophy (PIA) and prostatic intraepithelial neoplasia (PIN) were observed accompanied with fibrosis hyperplasia in stroma. The decrease in basal cells (Cytokeratin (CK) 5+/p63+) and the accumulation of luminal epithelial cells (CK8+) in the PIA or PIN area indicated that the basal cells were damaged or transformed into different luminal cells. Hic1, Zfp148, and Mfge8 gene mutations were detected in chronic prostatitis somatic cells. CONCLUSION: Chronic prostatitis induced by prostate extract protein immunization or E. coli infection caused a reactive prostatic inflammation microenvironment and resulted in tissue damage, aberrant atrophy, hyperplasia, and somatic genome mutation.

Evaluación de susceptibilidad y respuesta al tratamiento con piperacilina/tazobactam en pacientes con infecciones por Escherichia coli productoras de β -lactamasas de espectro extendido (BLEE) CTX-M / Evaluation of susceptibility and response to therapy with piperacillin-tazobactam in patients with infections caused by Escherichia coli with extended-spectrum β -lactamase (ESBL) CTX-M

Resumen Introducción: En las infecciones por enterobacterias productoras de β-lactamasas de espectro extendido (BLEE), los β-lactámicos preferidos para tratamiento son los carbapenémicos. Sin embargo, estudios clínicos muestran eficacia de piperacilina/tazobactam en ciertas infecciones por Escherichia coli productoras de BLEE. Objetivo: Determinar la cura clínica y microbiológica con piperacilina/tazobactam en pacientes con infecciones por E. coli productoras de BLEE, tipo CTX-M. Materiales/Métodos: Estudio descriptivo, retrospectivo, con adultos internados en un hospital universitario. Incluimos infecciones del tracto urinario (ITU), intra-abdominales (IIA) e infecciones de tejidos blandos (ITB). Resultados: Estudiamos 40 pacientes, donde 65% correspondían a ITU, 25% IIA y 10 % ITB. La cura clínica global se logró en 89,4%, con mejores resultados en las ITU (100%), seguidas de ITB (80%) e IIA (70%). El 85% de las cepas tenía concentraciones inhibitorias mínimas (CIM) ≤ 8 μg/mL y 70% con CIM ≤ 4 μg/mL. La tasa de fracaso fue mayor en las infecciones con inóculos altos intraabdominales. La BLEE del tipo CTX-M-15 se encontró en 62,5%. Conclusiones: Piperacilina/tazobactam logró cura clínica y microbiológica, en pacientes con infecciones por E. coli productoras de BLEE susceptibles, especialmente en ITU e IPB y en menor medida en IIA.

Background: Carbapenems are the preferred β-lactamics for treatment for infections caused by enterobacteria producing extended-spectrum β-lactamases (ESBL); however, clinical studies show effectiveness of piperacillin/tazobactam in certain infections by Escherichia coli ESBL producers. Aim: To determine the clinical and micro-biological cure with piperacillin/tazobactam in patients with infections caused by E. coli ESBL producers, CTXM type. Methods: Retrospective descriptive study with adults hospitalized in a university hospital. We included urinary tract infections (UTI), intra-abdominal infections (IAI), soft tissue infections (STI) and/or bacteremia. Results: We studied 40 patients, where 65% corresponded to UTI, 25% to IAI and 10% were STI. The overall clinical cure was achieved in 89.4%, with the best results in the ITU (100%), followed by STI (80%) and 70% in IAI. The 85% of the strains had minimum inhibitory concentrations (MIC) ≤8 μg/ml and 70% with MIC ≤4 μg/mL, however the rate of failure were high in intra-abdominal infections with high inocula or not controlled; CTX-M-15 was found in the 62.5%. Conclusions: Piperacillin/tazobactam was efficient to obtain clinical and microbiological cure in patients with infections caused by ESBL producers but susceptible E. coli, especially in UTI and STI and to a lesser extent in IAI.

Factores de riesgo asociados al aislamiento de Escherichia coli o Klebsiella pneumoniae productoras de betalactamasas de espectro extendido en un hospital de cuarto nivel en Colombia / Risk factors associated with the isolation of extended spectrum betalactamases producing Escherichia coli or Klebsiella pneumoniae in a tertiary care hospital in Colombia

Introducción. Las betalactamasas de espectro extendido (BLEE) son un fenómeno de resistencia emergente de particular incidencia en América Latina. En Colombia existe poca información sobre los factores de riesgo asociados con su adquisición. Objetivo. Determinar los factores de riesgo que están asociados a la infección o colonización por Escherichia coli o Klebsiella pneumoniae productoras de BLEE en pacientes mayores de 18 años. Materiales y métodos. Se llevó a cabo un estudio de casos y controles con relación 1:1 en pacientes con aislamientos de E. coli o K. pneumoniae productoras de BLEE en cualquier tipo de muestra durante el periodo de enero de 2009 a noviembre de 2011 en el Hospital Universitario de San José. Resultados. Se estudiaron 110 casos y 110 controles; 62,7 % correspondió a E. coli y 37,3 %, a K. pneumoniae . Como factores de riesgo independiente en el análisis multivariado se encontraron la insuficiencia renal crónica (OR=2,99; IC 95%, 1,10-8,11; p=0,031), la cirugía urológica (OR=4,78; IC 95%, 1,35-16,87; p=0,015), el antecedente de uso de antibióticos en los tres meses anteriores (OR=2,24; IC 95%, 1,09-4,60; p=0,028), el origen hospitalario de la infección (OR=2,92; IC 95%, 1,39-6,13; p=0,004) y la hospitalización previa (OR=1,59; IC 95%, 1,03-2,46; p=0,036). Conclusión. Anticiparse al patrón de resistencia del microorganismo que infecta a un paciente con base en los factores de riesgo asociados permitiría la elección de un tratamiento antibiótico empírico apropiado, con el fin de lograr la disminución de la morbimortalidad de los pacientes.

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Profile resistance of pathogens causing urinary tract infection in the pediatric population, and antibiotic treatment response, at a University Hospital 2010-2011 / Perfil de resistencia de los patógenos causantes de infección urinaria en la población pediátrica y respuesta al tratamiento antibiótico, en un hospital universitario 2010-2011

Abstract Background: Urinary tract infection (UTI) is one of the most common bacterial infections in childhood and causes acute and chronic morbidity as hypertension and chronic kidney disease. Objectives: To describe the demographic characteristics, infectious agent, antibiotic resistance patterns and empiric therapy response of UTI in pediatric population. Methods: This is a descriptive, retrospective study. Results: Were included 144 patients, 1:2.06 male to female ratio. The most common symptom was fever (79.9%) and 31.3% had history of previous UTI. 72.0% of the patients had positive urine leukocyte count (>5 per field), urine gram was positive in 85.0% of samples and gram negative bacilli accounted for 77.8% for the total pathogens isolated. The most frequent uropathogens isolated were Escherichia coli and Klebsiella pneumoniae. Our E.coli isolates had a susceptibility rate higher than 90% to most of the antibiotics used, but a resistance rate of 42.6% to TMP SMX and 45.5% to ampicillin sulbactam. 6.3% of E. coli was extended-spectrum beta-lactamases producer strains. The most frequent empirical antibiotic used was amikacin, used in 66.0% of the patients. 17 of 90 patients who undergone voiding cistouretrography (VCUG) had vesicoureteral reflux. Conclusion: This study revealed that E. coli was the most frequent pathogen of community acquired UTI. We found that E. coli and other uropathogens had a high resistance rate against TMP SMX and ampicillin sulbactam. In order to ensure a successful empirical treatment, protocols should be based on local epidemiology and susceptibility rates.

Resumen Antecedentes: La infección del tracto urinario (ITU) es una de las infecciones bacterianas más frecuentes en la infancia, se asocia con alta morbilidad aguda y de enfermedades a largo plazo como hipertensión arterial e insuficiencia renal crónica. Objetivo: Describir las características demográficas, agente etiológico, perfil de sensibilidad y respuesta al tratamiento empírico de una población pediátrica. Métodos: Estudio descriptivo, retrospectivo realizado en el Hospital Pablo Tobón Uribe (HPTU), Medellín (Colombia), entre enero de 2010 y diciembre de 2011. Resultados: Se incluyeron 144 pacientes, con una relación hombre: mujer de 1:2.06. El 79.9% consultó por fiebre objetiva y el 31.3% había tenido un episodio de ITU previa. El 72.0% presentó leucocituria y el gram de gota de orina sin centrifugar fue positivo en el 86.0% (77.8% de bacilos con tinción de gram negativos). Los uropatógenos más frecuentes fueron Escherichia coli y Klebsiella pneumoniae. Escherichia coli tuvo una sensibilidad mayor al 90% para la mayoría de antibióticos, excepto en el de trimetropín sulfametoxazol, con una resistencia del 42.6% y del 45.5% a la ampicilina sulbactam. Se usó la amikacina como tratamiento empírico en el 66.0%. En 17 de 90 pacientes se encontró algún grado de reflujo vesicoureteral (RVU). Conclusión: La elección del tratamiento empírico precoz debe basarse en el conocimiento de la epidemiología y el perfil de sensibilidad y resistencia de cada institución. En este estudio se encontró elevado porcentaje de resistencia de la E. coli y otros uropatógenos a trimetropín sulfametoxazol y ampicilina sulbactam.

Componentes alimentarios de potencial aplicación en la dietoterapia de enfermedades provocadas por cepas de escherichia coli productoras de toxina tipo shiga / Food components of potential application in the dietoterapia of diseases provoked by vine-stocks of escherichia coli producers of toxin type shiga

En Argentina, Escherichia coli O157:H7 es el serotipo prevalente asociado a grandes brotes y casos esporádicos de colitis hemorrágica y síndrome urémico hemolítico (SUH), siendo el país con mayor tasa de incidencia en el mundo con alrededor de 500 nuevos casos por año. El SUH representa la principal causa de falla renal aguda en la infancia, la segunda causa de falla renal crónica y el 20% de los casos de transplante renal durante la infancia y la adolescencia. Se ha demostrado que la habilidad de la cepa para causar la enfermedad está relacionada a la acción de factores de virulencia implicados en el proceso de colonización del epitelio intestinal con posterior reacción inflamatoria y por la capacidad de secretar toxinas VT1 y VT2 responsables del daño del endotelio vascular con el consecuente desarrollo de SUH. En la presente tesis doctoral se investigó desde la dietoterapia, extractos de origen vegetal y componentes de cepas probióticas potencialmente útiles en la inhibición de la colonización de E. coli O157:H7 a nivel intestinal como medida preventiva, e inhibición de la acción citotóxica de VT sobre células eucariotas. Se determinaron componentes fenólicos obtenidos a partir de la maceración de harina de algarroba (Prosopis alba) y café de mistol (Ziziphus mistol) en distintos solventes (alcohol, agua destilada, acetona y hexano). Los mismos fueron nalizados mediante marcha analítica fitoquímica, cromatografía en capa delgada y cuantificados por espectrofotometría. Por otro lado se obtuvieron componentes de leche fermentada con granos de kéfir.

SUMMARY: In Argentina, Escherichia coli O157:H7 is prevalent serotype associated with large outbreaks and sporadic cases of hemorrhagic colitis and hemolytic uremic syndrome (HUS), being the country with the highest incidence rate in the world with about 500 new cases per year. HUS is the leading cause of acute renal failure in infancy, the second leading cause of chronic renal failure and 20% of cases of renal transplantation during childhood and adolescence. It has been shown that the ability of the strain to cause disease is linked by the action of virulence factors required in the colonization of intestinal epithelium and subsequent inflammatory response and their ability to secrete toxins, VT1 and VT2 responsible for damage to the vascular endothelium with the subsequent development of HUS. In this thesis we investigated plant extracts and components of probiotic strains potentially useful in diet therapy to inhibit the colonization of E. coli O157:H7 in the intestine as a preventive measure, able to interfere the cytotoxic action of VT on eukaryotic cells. Phenolic compounds were identified, they were obtained from plant extracts of P. alba and Z. mistol macerated in different solvents (alcohol, distilled water, acetone and hexane). They were analyzed using phytochemical methods, thin layer chromatography and quantified by spectrophotometry. Furthermore components were obtained from fermented milk kefir grains.

Estudo do perfil de resistência antimicrobiana das infecções urinárias em mulheres atendidas em hospital terciário / Study of antimicrobial resistance profile of urinary tract infections in women attended at a tertiary hospital

JUSTIFICATIVA E OBJETIVOS: As infecções do trato urinário (ITU) representam significativa morbidade na população e elevados custos nos cuidados de saúde, sendo cada vez mais comum o isolamento de cepas resistentes em pacientes não internados.O objetivo deste estudo foi avaliar a frequência e o perfil de resistência antimicrobiana dos uropatógenos que acometeram mulheres na cidade de Vitória, ES. MÉTODO: Estudo retrospectivo, baseado nos arquivos da microbiologia do hospital Universitário da Santa Casa de Misericórdia de Vitória (HSCMV), no período de novembro de 2007 a março de 2010. Foram incluídas todas as uroculturas, sem limite de idade, oriundas da demanda ambulatorial. RESULTADOS: Foram analisadas 5564 uroculturas, sendo 585(10,5%) positivas, 4440 (79,8%) negativas e 539 (9,7%) contaminadas.Houve diferença significativa na média de idade do grupo com resultado positivo (43,62) e negativo (40,04), mas não houve diferença de média de idade quando se relacionou idade e micro-organismo isolado. Os uropatógenos mais comumente isolados foram: E. coli (69,9%), Klebsiela pneumoniae (6%), Staphylococcus saprophyticus (5,1%) e Proteus mirabilis (3,1%). O antibiótico que apresentou o maior índice de resistência, tanto para E. Coli (44%),quanto para os demais micro-organismos (16,6%), foi a ampicilina. Observou-se, ainda, tendência significativa de resistência da E.Coli ao ciprofloxacino ao longo dos meses estudados.CONCLUSÃO: Este tipo de monitoramento constitui importante ferramenta na escolha antibiótica empírica segura e eficaz, de forma a evitar erro terapêutico, diminuindo a morbimortalidade,os custos e o desenvolvimento de multirresistência bacteriana.

BACKGROUND AND OBJECTIVES: The infection of the urinary tract (ITU) represents significant morbidity in the population, and elevated costs in health care, with the isolation of resistant strains in nonhospitalized patients being increasingly more common. Our goal was to evaluate the frequency and the profile of antimicrobial resistance of uropathogens that affected women in the city of Vitoria, in the state of Espírito Santo. METHOD: Retrospective study based on the archives of microbiology from the University Hospital of Santa Casa de Misericórdia de Vitória (HSCMV), ES, from November 2007 to March 2010. All urocultures from outpatient's were included, with no limit of age. RESULTS: We analyzed 5564 urocultures, with 585 (10.5%) being positive, 4440 (79.8%) negative and 539 (9.7%) contaminated. There was significant difference in the mean age in the group with positive results (43.62) compared to the negative group (40.04), but there was no difference of mean age when age and microorganism isolated were compared. The more common isolated uropathogens were: E.coli (69.9%) Klebsiela pneumoniae (6%), Staphylococcus saprophyticus (5.1%), and Proteus mirabilis (3.1%). The antibiotics that presented the higher level of resistance, both for E.coli (44%) and for the other microorganisms (16.6%), was ampicillin. A significant tendency for resistance was also observed of E.coli to ciprofloxacin through the months of the study. CONCLUSION: This type of monitoring is an important toolw hen choosing empirical antibiotics that are safe and efficient, inorder to avoid therapeutic error, decrease morbimortality, costs, and the development of bacterial multiresistance.

Epidemiología del síndrome urémico hemolítico en dos regiones de la Provincia de Buenos Aires / Epidemiology of hemolytic uremic syndrome in two regions of Buenos Aires Province

Los objetivos de este estudio fueron describir y comparar la frecuencia del síndrome urémico hemolítico (SUH), registrada durante el periodo 2005-2010 en pobladores rurales y urbanos de la región centro-sur de la provincia de Buenos Aires y caracterizar la distribución de factores hipotéticos asociados al SUH en ambas poblaciones. Se caracterizaron 82 casos de SUH clínica y epidemiológicamente. Para el análisis estadístico de los datos se utilizó el test de Chi² o test exacto de Fisher cuando fue necesario, y el test de la mediana. La incidencia específica fue 12.7 casos cada 100 000 habitantes rurales (IC 0-23.5) y 7.1 casos cada 100 000 habitantes urbanos (IC 0-9.5). La mediana de la edad en el total de los pacientes estudiados fue de 27 meses (5-139 meses), siendo significativamente más baja en los niños del área rural. Estos resultados podrían explicarse por el contacto más frecuente con materia fecal de bovinos, el mayor consumo de leche sin pasteurizar y la mayor proporción de familiares que realizan actividades de riesgo, encontrados en la subpoblación rural. Aunque el SUH es una enfermedad que se asocia frecuentemente con el consumo de carne picada, la mayor parte de los niños que enfermaron no presentaron este antecedente. Las manifestaciones clínicas fueron semejantes en ambas subpoblaciones. Un tercio de los pacientes urbanos había recibido tratamiento con antibióticos previo al desarrollo del SUH.

The objectives of this study were (a) to describe and estimate the frequency of hemolytic uremic syndrome (HUS) in rural and urban populations in two regions of Buenos Aires Province, and (b) to compare the presentation and distribution of factors hypothetically associated with HUS. A total of 82 HUS cases, recorded during the years 2005-2010 in rural and urban areas of the south-central region of Buenos Aires Province, were clinically and epidemiologically characterized. Statistical data analysis included Chi square or Fisher test and median test. The incidence rate of HUS was significantly higher in the rural population, being 12.7 cases per 100 000 (CI 0-23.5) in rural inhabitants vs. 7.1 cases per 100 000 (CI 0-9.5) in urban inhabitants. The median age of the patients was 27 months (5-139 months), significantly lower in children from the rural area. This could be explained by a more frequent contact with bovine feces, the consumption of raw milk and a higher proportion of relatives who work in risk labors found in the rural population. Although HUS is often associated with the consumption of undercooked minced meat, most of the children cases here included did not present this antecedent. Clinical manifestations were similar in both subpopulations. One-third of urban patients had received antibiotics prior to HUS development.

Escherichia coli diarreogénica asociada a casos de diarrea aguda en niños de Cumaná, Venezuela / Diarrheagenic Escherichia coli associated with acute diarrhea in children of Cumana, Venezuela

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.

Detección de Escherichia coli diarreogénicos en niños de barrios humildes de Corrientes, Argentina / Detection of diarrheagenic Escherichia coli in children from poor neighborhoods in Corrientes, Argentina

INTRODUCCIÓN: las diarreas agudas presentan elevada morbilidad y mortalidad en los países en vías de desarrollo y Escherichia coli diarreogénicos aparecen como agentes etiológicos frecuentes en todos ellos. OBJETIVO: estudiar la presencia de los diferentes tipos de Escherichia coli diarreogénicos en niños que concurrieron a Centros de Salud de barrios humildes de la ciudad de Corrientes, Argentina. MÉTODOS: se cultivaron heces de 120 pacientes con diarrea aguda y en aquellas muestras negativas para Salmonella y Shigella se seleccionaron aislamientos de E. coli, cuyos factores de patogenicidad fueron estudiados mediante reacción en cadena de la polimerasa múltiple. RESULTADOS: los 112 pacientes estudiados habitaban viviendas urbanas, con suministro de agua potable y baño instalado. En 41 muestras (37 por ciento) se detectó algún tipo patogénico de Escherichia coli diarreogénico sin predominio marcado de ninguno de ellos. No se hallaron diferencias significativas entre la presencia de estos y el sexo o el grupo etario. CONCLUSIONES: Escherichia coli diarreogénico aparece como un agente etiológico habitual en niños y el reconocimiento de cada tipo implicado permitirá implementar medidas preventivas acordes con la epidemiología de cada uno de ellos.

INTRODUCTION: acute diarrheas bring high morbidity and mortality in developing countries and diarrheagenic Escherichia coli (DEC) appears as frequent etiological agent in all these places. OBJECTIVE: to detect the presence of pathogenic types of DEC in children attending the Health Centers in poor neighborhoods in the city of Corrientes, Argentina. METHODS: Feces from one hundred and twenty patients were cultured; E. coli isolates were selected in those cases negative for Salmonella or Shigella, and they were studied by multiplex PCR in order to characterize the pathogenic types of DEC. RESULTS: one hundred and twelve patients were included. All of them had urban housing with drinking water supply and toilet. In 41 samples (37 percent) some DEC type was detected but none of them (STEC 7, EPEC 7, EIEC 7, EAEC 10, and ETEC 10) was predominant. There were not significant differences between the DEC pathogenic types and the sex or the age group of patients. CONCLUSIONS: DEC is frequent etiologic agent in children and the recognition of each pathogenic type will allow implementing prophylactic measures according with its epidemiology.

Bloodstream infections caused by ESBL-producing E. Coli and K. pneumoniae: risk factors for multidrug-resistance

This prospective case-control study was conducted from October 2003 to June 2007 to evaluate risk factors for multidrug resistance among extended-spectrum-b-lactamase-producing Escherichia coli and Klebsiella spp. (ESBL-EK) isolates in blood cultures. All adult patients (>18 years old) whose blood cultures grew ESBL-EK during the study period were included. An ESBL-EK isolate was defined as MDR if it was resistant to at least one member of following two classes of antibiotics: aminoglycosides (amikacin, gentamicin, or netilmycin) and fluoroquinolones (ofloxacin, or ciprofloxacin). Case patients were those with a MDR ESBL-EK isolate, and control patients were those with a non-MDR ESBL-EK isolate. A total of 94 bloodstream infections, including 37 (39,4 percent) bloodstream infections with ESBL-producing E. coli and 57 (60,6 percent) with ESBL-producing K. pneumoniae,in 86 patients were enrolled. Thirty episodes (31.9 percent) were due to MDR ESBL-EK. The only independent risk factor for MDR ESBL-EK was duration of hospitalization before bacteraemia (OR 3.88; 95 percent CI 1.55-9.71; p=0.004). The rate of multidrug resistance among ESBL-EK bloodstream isolates was high, and duration of hospitalization before bacteraemia was the only indeepended risk factor for the MDR ESBL-EK bloodstream infections.

Síndrome urémico hemolítico inducido por Escherichia coli enterohemorrágica / Hemolytic uremic syndrome caused by enterohaemorrhagic Escherichia coli

El síndrome urémico hemolítico (SUH) se caracteriza por anemia hemolítica microangiopática, plaquetopeniay daño renal. Constituye la primeracausa de insuficiencia renal aguda en la edad pediátrica y la segunda de insuficiencia renal crónica.Escherichia coli productor de toxina Shiga (STEC,por su sigla en inglés) es el primer agente etiológico de SUH; su principal reservorio es el ganado bovinoy la vía de transmisión, los alimentos contaminados.Hasta el presente no existe un tratamiento específicopara disminuir la progresión del SUH.El estudio de los mecanismos por los cuales STEC infecta y la toxina Shiga induce SUH puede ayudar a desarrollar nuevas estrategias para impedir estaenfermedad.

Effects of structural injure in the bile bacterial contamination after balloon transduodenal sphincteroplasty (papillary dilation) in dogs / Efeitos da lesão estrutural na contaminação bacteriana biliar após a esfincteroplastia transduodenal (dilatação papilar) em cães

PURPOSE: To evaluate, in dogs, the biliary sphincter subjected to dilation by hydrostatic balloon by the point of view of structural alterations of the papilla and the biochemestry and bacterial contamination of the bile. METHODS: Twenty dogs were submitted to laparotomy, duodenotomy, and enlargement of the major duodenal papilla- GA(n=10) - with balloon of 8mm inflated with pressure of 0,5atm, during 2 minutes or to the sham procedure - GB(n=10). Blood samples collected on times t(0day), t(7days) and t(28days) were subjected to dosages of alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) for cholestasis evaluation. The collected material from the gall bladder at the same times were registered and numbered to be submitted to culture in BHI, blood agar (rich, non-selective element) and Mac Conkey (selective element for Gram-negative bacillus. On the 28th day three fragments of the papilla were tranversally cut by the choledoc axis 3mm from the duodenal papilla and the cuts, stained with hematoxylin-eosin and Masson's tricome, were evaluated according to their inflammatory reaction. RESULTS: The GGT and ALP averages on the three periods in the groups A and B did not show significant differences, not being characterizes the cholestasis. The bacterian contamination was significantly higher in GA (2,19) than in GB (1,96); the contamination was lower in the initial time compared with 7 and 28 days (t0

OBJETIVO: Avaliar, em cães, a papila duodenal maior submetida à dilatação por balão hidrostático sob o ponto de vista das alterações estruturais da papila e da bioquímica e contaminação bacteriana da bile. MÉTODOS: Vinte cães foram submetidos a laparotomia, duodenotomia, dilatação da papila maior GA (n=10) - com balão de 8mm insuflado com pressão de 0,5atm, durante 2 minutos ou ao procedimento simulado - GB(n=10). Amostras de sangue coletadas nos tempos t(0dia), t(7dias) e t(28dias) foram submetidas às dosagens da fosfatase alcalina (FA) e gama-glutamil-transferase (GGT) para avaliação da colestase. Material colhido da vesícula biliar nos mesmos tempos foi registrado e numerado para ser submetido à cultura em BHI, ágar sangue (meio rico não seletivo), e Mac Conkey (meio seletivo para bacilos Gram-negativos). No 28°. dia três fragmentos da papila forma cortados transversalmente ao eixo do colédoco a 3mm da papila duodenal e os cortes corados em hematoxilina-eosina e tricômio de Masson e avaliados quanto a reação inflamatória. RESULTADOS: As médias da GGT e da FA nos três períodos nos grupos A e B não mostraram diferenças significantes, não sendo caracterizada a colestase. A contaminação bacteriana foi significante maior em GA(2,19) que no GB(1,96); a contaminação foi menor no tempo inicial em relação aos 7 e 28 dias( t0

Agentes causantes de diarrea en niños menores de 5 años en Tunja, Colombia / Diarrhoea-causing agents in children aged less than five in Tunja, Colombia

Objetivos: Determinar la prevalencia y tipo de agentes infecciosos causantes de EDA en una muestra de niños menores de 5 años que consultaron a IPS de Tunja durante el año 2004. Materiales y Métodos Estudio de corte transversal, la información se recogió mediante aplicación de una encuesta a 129 niños menores de 5 años afectados de EDA. Adicionalmente se recogió una muestra de heces, en las consultas externas del Hospital San Rafael y Clínica Saludcoop de Tunja. Resultados Se encontró Rotavirus en 48,1 por ciento, Shigella 0,8 por ciento, E. coli 13,9 por ciento; Campylobacter 2,3 por ciento; Giardia lamblia 12,4 por ciento; E. histolytica 7 por ciento; en 15,5 por ciento de casos no se identificó agente causal. La asociación es creciente con la edad para Rotavirus (p<0,01), E.Coli (p<0,05) y Campylobacter (p<0,001). Conclusión Rotavirus es el mayor agente causal de EDA en menores de 1 año, y en general, en menores de 5 años. Las prevalencias encontradas coinciden con lo reportado en estudios realizados en Facatativá, Bogotá, Santander, Manizales y Chocó; también con estudios adelantados en Venezuela, Perú y México.

Objectives: Determining the prevalence and type of infectious ADD-causing agents in a sample of children aged less than five who consulted the IPS in Tunja during 2004. Material and Methods A cross-sectional study was designed. Data was obtained by surveying 129 children younger than 5 suffering from ADD. Samples of faeces were obtained following outpatient consultation at San Rafael Hospital and SaludCoopÆs clinic in Tunja. Results Rotavirus was found in 48,1 percent of cases, Shigella in 0,8 percent, E. coli in 13,9 percent, Campylobacter in 2,3 percent, Giardia lamblia in 12,4 percent and E. hitolytica in 7 percent. The causative agent could not be identified in 15,5 percent of cases. The statistical association grew with age for Rotavirus (p<0.01), E. coli (p<0.05) and campylobacter (p<0.001). Conclusion Rotavirus is the major causative agent of ADD in children younger than one year and, generally, in children aged less than five. The prevalence found was similar to data reported in studies carried out in Facatatativá, Bogotá, Santander, Manizales and the Chocó in Colombia and studies carried out in Venezuela, Peru and Mexico.

Síndrome hemolítico urémico: Experiencia de un centro pediátrico / Hemolytic uremic syndrome: The experience of a pediatric center

Background:Hemolytic uremic syndrome (HUS) is one of the main causes of acute renal failure in the Chilean pediatric population. Aim: To report the features of patients with HUS, admitted to the pediatric ward of a clinical hospital. Material and methods: Retrospective review of medical records of patients admitted with the diagnosis of HUS between 1995 and 2002. Results: During the period, 58 patients were admitted with the diagnosis of HUS but only 43 (age range 1 month to 6 years, 22 females) had complete medical records for review. Ninety five percent presented with prodromic diarrhea, mainly dysenteric. Antibiotics were administered to 70%, in the previous days. Acute renal replacement, mainly peritoneal dialysis, was required in 40%. The clinical signs and laboratory parameters that correlated better with the indication for dialysis were anuria, hypertension, initial and permanently high serum creatinine and blood urea nitrogen. Four patients with blood urea nitrogen over 100 mg/dl but without anuria or hyperkalemia, were treated conservatively, and experienced an uneventful course (permissive azotemia). Hospital stay was almost 3 times greater in dialyzed than in non dialyzed children. No deaths related to HUS were reported in the study period. In an average follow up of 54 months, 11.6% of the patients developed chronic renal failure of diverse magnitude. Conclusions: Despite the fact that our study group behaved clinically similar to published HUS patients in other series, no mortality was observed in a retrospective analysis of patients with this disease.

Nosocomial blood stream infections in Imam Khomeini Hospital, Urmia, Islamic Republic of Iran, 1999-2001

In a 2-year retrospective study, the database of the microbiology laboratory of the Imam Khomeini Hospital was reviewed to identify patients who had nosocomial bacteraemia between 1 May 1999 and 31 May 2001 and identify the pathogen responsible and its resisitance to antibiotics. Of 6492 patients in various wards, 593 [9.1%] had positive blood cultures; 85 of those [14.3%] had signs of potential skin contamination. Gram-positive cocci, including coagulase-negative staphylococci, Staphylococcus aureus, Streptococcus pneumoniae and other Gram-positive cocci, accounted for 42.3% of isolates. Gram-negative bacilli were responsible for another 42.3% of isolates; Pseudomonas aeruginosa was the predominant isolate. Patterns of drug resistance varied according to species of bacteria but were generally quite high

Escherichia coli enterohemorragica y sindrome uremico hemolitico en Argentina / Enterohemorrhagic escherichia coli and hemolytic-uremic syndrome in Argentina

El síndrome urémico hemolítico (SUH) es un desorden multisistémico caracterizado por presentar insuficiencia renal aguda, anemia hemolítica microangiopática y trobocitopenia. Constituye la principal causa de insuficiencia renal aguda y la segunda causa de insuficiencia renal crónica y de transplante renal en niños en la Argentina. Actualmente, nuestro país presenta el registro más alto de SUH en todo el mundo, con aproximadamente 420 casos nuevos declarados anualmente y una incidencia de 12.2/100 000 niños menores de 5 años de edad. Se reconocen múltiples agentes etiológicos, aunque se considera a la infección por Escherichia coli enterohemorrágica (EHEC) como la principal etiología de SUH. La gran mayoría de brotes epidémicos y casos esporádicos en humanos se han asociado con el serotipo 0157:H7, aunque otros serotipos han sido también aislados, y éstos son un subgrupo de E.coli verocitotoxigénico (VTEC). El bovino es considerado el principal reservario de VTEC. El contagio al hombre frecuentemente se debe al consumo de alimentos cárneos y lácteos contaminados, deficientemente cocidos o sin pasteurizar, o al contacto directo con los animales o con sus heces, consumo de agua, frutas o verduras contaminadas. También puede producirse contagio mediante el contacto interhumano.

Neonatal septicaemia in the neonatal care unit, Al-Anbar governorate, Iraq

Neonatal septicaemia is a major cause of morbidity and mortality in developing countries. We studied 118 neonates admitted to the main referral hospital in Al-Anbar with positive blood cultures. The incidence of neonatal septicaemia for babies born at this hospital was 9.2 per 1000 live births, and mortality was 28%. Staphylococcus aureus [39%], Klebsiella pneumoniae [30%] and Escherichia coli [21%] constituted 90% of all isolates. The isolates showed in vitro susceptibility to cefotaxime, chloramphenicol and gentamicin, but resistance to more commonly used antibiotics such as ampicillin and cloxacillin. We recommend initial gentamicin/cefotaxime combined therapy while awaiting culture and sensitivity test results. Our study highlights the importance of understanding the local epidemiology of neonatal septicaemia in formulating a rational antibiotics policy