Síndrome urémico hemolítico del adulto / Adult hemolytic uremic syndrome

El síndrome urémico hemolítico (SUH), descripto en 1955, se caracteriza por la tríada de anemia hemolítica no inmunomediada, trombocitopenia y lesión renal aguda. En su patogenia interviene la toxina Shiga, producida con mayor frecuencia por E. coli O157:H. Puede manifestarse a cualquier edad, aunque es infrecuente en adultos, y se desarrolla en forma esporádica o en brote. Se presenta con un cuadro de dolor abdominal, diarrea, fiebre y vómitos. Puede afectar el sistema nervioso central, pulmones, páncreas y corazón. En adultos, el síndrome evoluciona tras un período de incubación de 1 semana posterior a la diarrea y tiene alta morbimortalidad, a diferencia de los casos pediátricos. Presentamos el caso de una paciente adulta, que cursó internación por síndrome urémico hemolítico. (AU)

Hemolytic uremic syndrome (HUS), described in 1955, is characterized by the triad of non-immune mediated hemolytic anemia, thrombocytopenia, and acute kidney injury. Shiga toxin, produced most frequently by E coli O157:H, is involved in its pathogenesis. Hus can manifest at any age, although it is rare in adults and develops sporadically or in outbreaks. HUS presents with a picture of abdominal pain, diarrhea, fever and vomiting. It can affect the central nervous system, lungs, pancreas, and heart.In adults, the syndrome evolves after an incubation period of 1 week after diarrhea, with high morbidity and mortality, unlike pediatric cases.We present the case of an adult patient who was hospitalized for hemolytic uremic syndrome. (AU)

Escherichia coli diarrogénicos, identificación de patotipos y fenotipos de resistencia antimicrobiana en aislados cubanos / Diarrheagenic Escherichia coli: identification of pathotypes and antimicrobial resistance phenotypes in Cuban isolates

Introducción: En los países en vías de desarrollo las enfermedades diarreicas agudas son causa frecuente de morbilidad y mortalidad. Entre las primeras causas se encuentra Escherichia coli diarrogénicos, que afecta a pacientes en edades extremas de la vida y con inmunodeficiencias. Objetivo: Identificar los patotipos de Escherichia coli diarrogénicos que más inciden y los fenotipos de resistencia antimicrobiana expresados por el patotipo predominante. Métodos: Se estudiaron 184 aislamientos procedentes de 15 centros provinciales de Higiene, Epidemiología y Microbiología de Cuba e Isla de la Juventud. La investigación se realizó desde julio de 2012 hasta febrero de 2014. La identificación de género, especie y patotipos fue realizada por métodos de diagnóstico convencional y molecular. La determinación de la susceptibilidad antimicrobiana se realizó por el método de Bauer y Kirby, y las normas del Clinical and Laboratory Institute Standards de 2013. Resultados: Se identificaron 108 (58 por ciento) Escherichia coli diarrogénicos. Los patotipos confirmados fueron: en la PCR múltiple 1, 5 (6 por ciento) de Escherichia coli enteropatogénico, 4 (4 por ciento) de enterotoxigénico y 0 (0 por ciento) de enterohemorrágico. La PCR múltiple 2 reveló 72 (82 por ciento) Escherichia coli enteroagregativo, que resultó el predominante en el estudio. La PCR 3 (simple) detectó 7 (8 por ciento) de enteroinvasivo. El 100 por ciento del patotipo predominante mostró resistencia, al menos a un antimicrobiano de los probados, un solo patron de resistencia a dos antimicrobianos, y nueve patrones de multirresistencia. Conclusiones: El estudio demuestra la importancia del uso de pruebas moleculares rápidas para la confirmación de los patotipos de E. coli diarrogénicos, los que provocan deshidratación ligera, complicaciones graves y la muerte. Se logra identificar los cuatro patotipos más frecuentes y E. coli enteroagregativo, el de mayor incidencia en la población estudiada. El patotipo predominante mostró altos porcentaje de resistencia antimicrobiana a betalactámicos y buena sensibilidad antimicrobiana a los aminoglucósidos y cefalosporinas de tercera generación. La investigación aporta conocimientos, no revelados en estudios anteriores con aislados cubanos, lo que es considerado de alto valor para los clínicos, pediatras y epidemiólogos del país(AU)

Introduction: Acute diarrheal disease is a frequent cause of morbidity and mortality in developing countries. One of the leading causes is diarrheagenic Escherichia coli, which affects patients at extreme ages and with immunodeficiencies. Objective: Identify the most active pathotypes of diarrheagenic Escherichia coli and the antimicrobial resistance phenotypes expressed by the prevailing pathotype. Methods: A study was conducted from July 2012 to February 2014 of 184 isolates obtained from 15 provincial Hygiene, Epidemiology and Microbiology Centers in Cuba and the Isle of Youth. Identification of the genus, species and pathotypes was based on conventional and molecular diagnostic methods. Determination of antimicrobial susceptibility was performed by the Bauer-Kirby method in compliance with guidelines from the Clinical and Laboratory Standards Institute of 2013. Results: A total 108 (58 percent) diarrheagenic Escherichia coli were identified. The following pathotypes were confirmed: Multiplex PCR 1 revealed 5 (6 percent) enteropathogenic, 4 (4 percent) enterotoxigenic and 0 (0 percent ) enterohemorrhagic Escherichia coli. Multiplex PCR 2 found 72 (82 percent) enteroaggregative Escherichia coli, which was the prevailing type in the study. PCR 3 (simple) detected 7 (8 percent) enteroinvasive Escherichia coli. 100 percent of the prevailing pathotype displayed resistance to at least one of the antimicrobials tested, a single resistance pattern to two antimicrobials, and nine multiresistance patterns. Conclusions: The study showed the importance of the use of rapid molecular tests to confirm diarrheagenic E. coli pathotypes, which cause mild dehydration, serious complications and death. Identification could be done of the four most common pathotypes and enteroaggregative E. coli, the one with the highest incidence in the study population. The prevailing pathotype displayed high percentages of antimicrobial resistance to beta-lactams and good antimicrobial sensitivity to third-generation cephalosporins and aminoglycosides. The study contributed knowledge not revealed by previous research about Cuban isolates. Such information is considered to be highly valuable for clinicians, pediatricians and epidemiologists in the country(AU)

Sepse em gestantes atendidas em um hospital público de Curitiba - PR / Sepsis in pregnant women attended at a public hospital in Curitiba - PR

OBJETIVO: Avaliar a frequência de sepse em gestantes e puérperas atendidas em um hospital, identificar os principais focos originários de sepse na gestação e puerpério, e verificar os principais agentes etiológicos envolvidos em sua etiopatogenia. MÉTODOS: Estudo do tipo transversal descritivo realizado no Hospital do Trabalhador, em Curitiba (PR), de agosto de 2014 a agosto de 2016. Revisão e análise de 71 prontuários de pacientes diagnosticadas com sepse, sepse grave ou choque séptico. Os aspectos estudados foram idades gestacional, agente etiológico, foco infeccioso, principal trimestre gestacional acometido e prevalência de cada tipo de sepse. RESULTADOS: A frequência de sepse durante a gestação e o puerpério no período estudado foi de nove casos para cada mil gestantes. A ocorrência de sepse foi relacionada principalmente ao segundo semestre gestacional (39,4%). Os casos de sepse somaram 73,2% do total, enquanto os demais evoluíram com quadros de sepse grave e choque séptico . Escherichia coli representou 33,8%, sendo o urinário o foco infeccioso mais prevalente (70,4%). Ceftriaxona foi o antibiótico mais utilizado, tanto isoladamente quanto em associação (84,4%). Entre os desfechos para o feto, 85,9% não tiveram complicações. CONCLUSÕES: Os novos conceitos de sepse publicados pela Society of Critical Care Medicine (SCCM) e pela European Society of Critical Care Medicine (ESICM) contrariam os interesses dos países conhecidos como de baixos e médios recursos. Foi encontrado aumento da incidência de sepse gestacional, ocorrendo prevalência do foco urinário; consequentemente, o agente principal foi E. coli. Ademais, ocorreram importantes consequências perinatais como mortalidade e prematuridade. (AU)

OBJECTIVE: To evaluate the frequency of sepsis in pregnant and puerperal patients attended in a hospital, and to identify the main focus of sepsis during gestation and puerperium, and check the main etiological agents involved in its pathogenesis. METHODS: This is a cross-sectional and descriptive study carried out at Hospital do Trabalhador (city of Curitiba, state of Paraná), from August 2014 to August 2016. It is a review and analysis of the charts of 71 patient diagnosed with sepsis, severe sepsis, or septic shock. Aspects studied: gestational age, etiologic agent, infectious focus, main affected gestational trimester, and prevalence of each type of sepsis. RESULTS: The frequency of sepsis during pregnancy and puerperium was 9 cases for 1000 pregnant women. The occurrence of sepsis was mainly related to the second gestational semester (39.4%). Severe sepsis and septic shock comprised 73.2% of the cases. Escherichia coli accounted for 33.8%, and the most prevalent infectious focus was urinary (70.4%). Ceftriaxone was the most commonly used antibiotic, both alone and in combination (84.4%). Among the outcomes for the fetus, 85.9% had no complications. CONCLUSIONS: The new concepts of sepsis, published by the Society of Critical Care Medicine (SCCM), and by the European Society of Critical Care Medicine (ESICM) contradict the interests of the countries with low and medium resources. An increase in the incidence of gestational sepsis occurred, with a prevalence of urinary focus; consequently the main agent was Escherichia coli. In addition, there were important perinatal consequences such as mortality and prematurity. (AU)

Desarrollo de un producto anti-toxina shiga para la prevención del síndrome urémico hemolítico / Development of a product anti-Shiga toxin for prevention of the hemolytic uremic syndrome

El síndrome urémico hemolítico (SUH) típico es una enfermedad huérfana causada por cepas de Escherichia coli productoras de toxina Shiga (Stx) y caracterizada por daño renal agudo, anemia hemolítica microangiopática y plaquetopenia. Es endémico en Argentina, el país con mayor incidencia de SUH en el mundo. Debido al rol fundamental de la Stx en su patogenia, se puede considerar que, como otras toxemias conocidas, el SUH podría ser tratado con anticuerpos. Este trabajo describe el desarrollo de un nuevo tratamiento capaz de neutralizar el efecto tóxico de distintas variantes de la Stx. El tratamiento consiste en fragmentos F(ab')2 provenientes de un antisuero equino cuya eficacia y potencia contra Stx1 y Stx2 se comprobó en diferentes modelos preclínicos. El producto mostró ser seguro en animales, presentó la farmacocinética descripta para compuestos similares y se pudo establecer una posible ventana terapéutica para su adecuada administración. En conjunto, los resultados preclínicos obtenidos validan la realización de un estudio clínico de primer uso en humanos. En dicho estudio, que se realizará en el Hospital Italiano de Buenos Aires, se analizará la seguridad y la farmacocinética del producto en voluntarios adultos sanos. Estos resultados sentarán las bases para la realización del estudio clínico fase II en pacientes pediátricos con infección por cepas de E. coli productoras de Stx.

The typical hemolytic uremic syndrome (HUS) is an orphan disease caused by Shiga toxin(Stx) -producing Escherichia coli strains and characterized by acute kidney damage, microangiopathic hemolytic anemia and low platelet count. It is endemic in Argentina, the country with the highest incidence of HUS in the world. Stx is essential for its development and therefore, HUS is considered a toxemic non-bacteremic disorder, which could be treated with antibodies. Herein we describe the development of a new treatment capable of neutralizing the toxic effect of Stx and its variants. The treatment consists of F(ab')2 fragments from an equine antiserum whose efficacy and potency against Stx1 and Stx2 were proved in different preclinical models. The product was shown to be safe in animals. Furthermore, the anti-Stx F(ab')2 pharmacokinetic was shown to be similar to that of analogous compounds and a therapeutic window for its administration was determined. Altogether, these preclinical results warrant testing in humans. The phase I clinical trial will be performed at the Hospital Italiano in Buenos Aires to evaluate the safety and pharmacokinetics of the product in healthy adult volunteers. Based on the results of this study, a phase II clinical trial will be planned in pediatric patients diagnosed with infection by Stx-producing E. coli strains.

Síndrome urémico hemolítico con compromiso renal leve debido a una cepa de Escherichia coli productora de toxina Shiga [Shiga-toxin-producing Escherichia coli (STEC)] 0145 / Hemolytic uremic syndrome with mild renal involvement due to Shiga toxin-producing Escherichia coli (STEC) 0145 strain

El síndrome urémico hemolítico (SUH) es una afección caracterizada por la presencia de la tríada clásica: anemia hemolítica microangiopática, trombocitopenia y compromiso renal agudo. Los casos de SUH sin insuficiencia renal pueden confundirse con otras enfermedades hematológicas. Presentamos un caso de SUH pediátrico causado por una cepa de Escherichia coli productora de toxina Shiga Shiga-toxin-producing Escherichia coli (STEC) O145 con el genotipo stx2, ehxA, eae subtipo ?1. El niño no requirió diálisis durante la etapa aguda del SUH, evolucionó favorablemente y no tuvo recurrencias hasta el último control; además, mantuvo cifras normales de presión arterial y función renal normal. Esto puede deberse a varios factores: características de la cepa STEC infectante y susceptibilidad del hospedero al daño renal, entre otros. Este hallazgo destaca la participación regional de STEC no-O157 en enfermedades de la infancia y la importancia de realizar una vigilancia activa de todas las formas de SUH

Hemolytic uremic syndrome (HUS) is a disorder characterized by the presence of the classic triad: microangiopathic hemolytic anemia, thrombocytopenia and acute renal injury. HUS without acute renal failure can be confused with other hematologic diseases. An infantile HUS caused by a Shiga-toxin-producing Escherichia coli (STEC) O145 strain carrying genotype stx2, ehxA, eae subtype ?1 is herein reported. The infant did not require dialysis during the acute stage of HUS, evolved favorably, maintained normal blood pressure and normal renal function and had no recurrence until the last control. This could be due to several factors, such as the characteristics of infecting STEC strain and a reduction in host susceptibility to renal injury. This report highlights the regional participation of non-O157 STEC in childhood diseases and the importance of performing active surveillance for all forms of HUS

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.

Successfully Treated Escherichia coli-Induced Emphysematous Cyst Infection with Combination of Intravenous Antibiotics and Intracystic Antibiotics Irrigation in a Patient with Autosomal Dominant Polycystic Kidney Disease

A 62-yr-old woman with an autosomal dominant polycystic kidney disease (ADPKD) was admitted to our hospital for further evaluation of intermittent fever, nausea and left flank discomfort. The computed tomography (CT) scan revealed a gas-forming, infectious cyst of approximately 8.1 cm in size in left kidney lower pole. Escherichia coli was identified from the cyst fluid culture examination. Her symptoms improved only after the concomitant use of intravenous ciprofloxacin and an intracystic irrigation of ciprofloxacin through a percutaneous cystostomy drainage. Our case presents the successfully treated emphysematous cyst infection with combination of intravenous antibiotics and intracystic antibiotic therapy instead of surgical management.

Detection & characterization of Shiga toxin producing Escherichia coli (STEC) & enteropathogenic Escherichia coli (EPEC) in poultry birds with diarrhoea.

Background & objectives Limited information is available on shiga toxin producing Escherichia coli (STEC) in animals and birds from India. An outbreak of acute diarrhoea in poultry birds at Aizawl, Mizoram was investigated for detection and characterization of STEC and enteropathogenic E. coli (EPEC). Methods E. coli was isolated and identified from rectal swabs, intestinal contents, heart blood and spleen of 19 poultry birds that died due to acute diarrhoea during the outbreak. Phenotypic characterization was done by standard bacteriological and biochemical techniques. All the isolates were serotyped based on their somatic antigens. Virulence genes (stx1, stx2, eaeA and hlyA) were detected by multiplex PCR assay. Results A total of 42 E. coli isolates were obtained, of which 24 belonged to 3 serogroups (O64, O89 and O91) and the remaining 18 were untypable (UT). Altogether, 14 (33.33%) isolates carried at least 1 virulence gene, of which 10 (23.81%) and 4 (9.52%) were recorded as STEC and EPEC, respectively. Of the 10 STEC isolates, one carried only stx2, one carried stx2 and hlyA, four carried stx1, stx2 and hlyA, two carried stx1, eaeA and hlyA genes and two carried stx1 and eaeA. Of the four EPEC isolates, two carried eaeA and hlyA, one carried only eaeA gene and 1 carried only hlyA gene. Interpretation & conclusions This is the first report on the involvement of STEC in poultry in India.

Enterotoxins, colonization factors, serotypes and antimicrobial resistance of enterotoxigenic Escherichia coli (ETEC) strains isolated from hospitalized children with diarrhea in Bolivia

Enterotoxigenic Escherichia coli (ETEC) is recognized as the main cause of bacterial diarrhoea among children in Asia, Africa and Latin America but less investigated in Bolivia. OBJECTIVE: To determine the relation between enterotoxins, CFs and serotypes as well as the antimicrobial resistance patterns in a set of ETEC isolates collected from hospitalized children with acute diarrhea. In the present study we characterized 43 ETEC strains isolated from 2002 to 2006 from hospitalized children (0-5 years) with acute diarrhea in Bolivia. The strains were analyzed for heat-labile (LT) and heat-stable (ST) enterotoxins and colonization factor (CF) profiles, as well as for serogroups and antimicrobial resistance using phenotypic (ELISA, dot blot, slide agglutination and disc diffusion) and genotypic (Multiplex PCR) methods. Among the ETEC isolates tested, 30 were positive for LT, 3 for STh and 10 for LT/STh. Sixty-five percent (28/43) of the strains expressed one or more CF. The most common CFs were CS17 (n = 8) and CFA/I (n = 8). The phenotypical and genotypical results for toxins and CFs were congruent except for CS21 that was amplified in 10 of the strains by multiplex PCR, but CS21 pili was only detected phenotypically in four of these strains. The ETEC strains had diverse O and H antigens and the most common types were O8:H9 LT CS17 (n = 6; 14 percent) and O78:HNM LT-ST CFA/I (n = 4; 9 percent). The analysis of antibiotic resistance showed that 67 percent (n = 29/43) of the strains were resistant to one or several of the antimicrobial agents tested. Presence of CFs was associated with antibiotic resistance. CONCLUSION: The most common toxin profile was LT 70 percent, LT/STh 23 percent and STh 7 percent. High antimicrobial resistance to ampicillin among serogroups O6, O8 and O78 were the most common.

Frecuencia y patotipos de Escherichia coli diarrogénicas en niños peruanos con y sin diarrea / Frequency and pathotypes of diarrheagenic Escherichia coli in peruvian children with and without diarrhea

Introducción. Las E. coli diarrogénicas (DEC) son una de las principales causas de diarrea en niños en países en vías de desarrollo. Sin embargo, no son rutinariamente diagnosticadas en los laboratorios clínicos. Objetivos. Determinar la prevalencia de las DEC en niños peruanos y describir la variabilidad genética de estas cepas. Materiales y métodos. Se utilizaron 8 003 cepas de E. coli previamente aisladas de ocho estudios previos de diarrea en niños, mayormente en zonas periurbanas de Lima. El diagnóstico de las DEC fue a través de un PCR múltiple a tiempo real para los seis grupos de DEC. Se empleó PCR para la determinación de genes adicionales de virulencia. Resultados. La prevalencia promedio global en muestras de diarrea (n=4 243) fue: E. coli enteroagregativa (EAEC) 9,9 por ciento, enteropatogénica (EPEC) 8,5 por ciento, enterotoxigénica (ETEC) 6,9 por ciento, difusamente adherente (DAEC) 4,8 por ciento, productora de toxina shiga (STEC) 0,8 por ciento y enteroinvasiva (EIEC) 0,6 por ciento. La frecuencia relativa de cada patógeno varía según la edad y tipo de estudio. Los principales patotipos en muestras control (n=3 760) fueron EPEC (10,9 por ciento) y EAEC (10,4 por ciento). Se encontró una gran variabilidad en la frecuencia de genes de virulencia para cada patotipo, así como en los mecanismos moleculares de resistencia, sin diferencias significativas entre muestras de diarrea y control. Conclusiones. Las DEC son causa importante de diarrea en niños peruanos. Estos patógenos son altamente heterogéneos. Se requieren estudios adicionales para determinar la prevalencia en zonas rurales del Perú, así como en casos graves de diarrea.

Introduction. Diarrheagenic E. coli (DEC) are a major cause of diarrhea in children in developing countries. However, they are not part of routine diagnosis in clinical laboratories. Objectives. To determine the DEC prevalence in Peruvian children and to describe the genetic variability of these strains. Materials and methods. A total of 8 003 E. coli strains previously isolated from eight different studies of diarrhea in children, mainly from peri-urban areas of Lima, were analyzed. Diagnosis of DEC was done with Multiplex real-time PCR using genes for each of the 6 DEC groups. Conventional PCR was performed for the detection of additional virulence genes. Results. Globally, the mean prevalence in diarrhea samples (n=4,243) was: enteroaggregative E. coli (EAEC) 9.9 percent, enteropathogenic E. coli (EPEC) 8.5 percent, enterotoxigenic E. coli (ETEC) 6.9 percent, diffusely adherent E. coli (DAEC) 4.8 percent, Shiga toxin-producing E. coli (STEC) 0.8 percent and enteroinvasive E. coli (EIEC) 0.6 percent. The relative frequency of each pathogen varies according to the age and the type of study. The main pathotypes in control samples (n=3,760) were EPEC (10.9 percent) and EAEC (10.4 percent). An important variability in the virulence genes frequency and molecular resistance mechanisms for each pathotype was found, without differences between diarrhea and control groups. Conclusions. DEC are a major cause of diarrhea in Peruvian children. These pathogens are highly heterogeneous. Additional studies are required to determine the prevalence in rural areas of Peru and in severe diarrhea cases.

Virulence factors and genetic variability of uropathogenic Escherichia coli isolated from dogs and cats in Italy

In this study, the association between virulence genotypes and phylogenetic groups among Escherichia (E.) coli isolates obtained from pet dogs and cats with cystitis was detected, and fingerprinting methods were used to explore the relationship among strains. Forty uropathogenic E. coli (UPEC) isolated from dogs (n = 30) and cats (n = 10) in Italy were analysed by polymerase chain reaction (PCR) for the presence of virulence factors and their classification into phylogenetic groups. The same strains were characterized by repetitive extragenic palindromic (REP)- and enterobacterial repetitive intergenic consensus (ERIC)-PCR techniques. We found a high number of virulence factors such as fimbriae A, S fimbriae (sfa) and cytotoxic necrotizing factor 1 (cnf1) significantly associated with phylogenetic group B2. We demonstrated a high correlation between alpha-hemolysin A and pyelonephritis C, sfa, and cnf1 operons, confirming the presence of pathogenicity islands in these strains. In addition, UPEC belonging to group B2 harboured a greater number of virulence factors than strains from phylogenetic groups A, B1, and D. REP- and ERIC-PCR grouped the UPEC isolates into two major clusters, the former grouping E. coli strains belonging to phylogenetic group B2 and D, the latter grouping those belonging to groups A and B1. Given the significant genetic variability among the UPEC strains found in our study, it can be hypothesized that no specific genotype is responsible for cystitis in cats or dogs.

Infecciones en la patogenia de la enfermedad inflamatoria intestinal / Infections in the pathogeny of inflammatory bowel disease

La enfermedad inflamatoria intestinal (EII) es una entidad compleja. Su desarrollo requiere de la interacción entre factores ambientales y la flora gastrointestinal, en un individuo genéticamente susceptible. Nuestro aparato gastrointestinal es un extraordinario, complejo y dinámico modelo de simbiosis o mutualismo con la flora. Los factores ambientales como el tabaco, las infecciones gastrointestinales y los antiinflamatorios no esteroidales juegan probablemente un rol iniciador y/o modificador de la enfermedad. La mucosa intestinal tiene la difícil tarea de limitar la respuesta inflamatoria contra la flora y de mantener la habilidad de generar una respuesta inmune contra los microorganismos patógenos. Esto crea una relación de equilibrio dinámico y frágil que al alterarse cualquiera de sus componentes puede generar un proceso inflamatorio. Existe evidencia que las infecciones pueden tener un rol tanto en el inicio de la enfermedad como en las reagudizaciones de ésta. Es así como las infecciones bacterianas gastrointestinales agudas y la Escherichia coli adherente invasora confieren un riesgo para desarrollar una enfermedad inflamatoria intestinal. Para Mycobacterium avium subespecie paratuberculosis (MAP) sólo se ha establecido una asociación y no un rol patogénico. Por último ha aumentado la incidencia y morbimortalidad de la infección por Clostridium difficile en los pacientes con EII.

Infections in the pathogeny of inflammatory bowel disease Inflammatory bowel disease (IBD) is a complex entity. Its development requires the interaction between environmental factors and gastrointestinal flora in a genetically susceptible subject. Our gastrointestinal tract is an extraordinary, complex and dynamic model of symbiosis or mutualism with the flora. Environmental factors such as tobacco, gastrointestinal infections and non-steroidal anti-inflammatory drugs might play a role of starter and/or modifier of the disease. The intestinal mucosa has the difficult task of limiting the inflammatory response against the flora and of keeping the capability of generating an immune response against pathogenic microorganisms. This creates a dynamic equilibrium relation that is fragile, and that when any of its components is altered, it can cause an inflammatory process. There is evidence that infections can have a role both in the beginning and in the episodes of New-Rebounds of the disease. Therefore, acute gastrointestinal bacterial infections and adherent-invasive Escherichia coli pose a risk of developing an inflammatory bowel disease. In the case of Mycobacterium avium subspecies paratuberculosis (MAP) an association has been established, but not a pathogenic role. The incidence and morbimortality of Clostridium difficile infection has increased in patients with IBD.

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.

Aspectos histomorfológicos e respiratórios em modelo de lesão pulmonar aguda por sepse em ratos tratados com pentoxifilina / Histomorphologic and respiratory aspects of acute lung injury in rats induced by experimental sepsis and under pentoxifylline treatment

OBJETIVO: Analisar as alterações histomorfológicas e respiratórias em modelo de lesão pulmonar aguda por sepse em ratos tratados com pentoxifilina. MÉTODOS: Foram utilizados 15 ratos adultos distribuídos em três grupos (n=5, por grupo), assim constituídos: GC - receberam apenas ventilação mecânica; GS - Animais sépticos tratados com solução salina e mecanicamente ventilados; GS+PTX - Animais sépticos, com infusão de pentoxifilina e mecanicamente ventilados. Todos os animais foram ventilados por um período de 180 minutos. Ao final deste período, foram avaliadas variáveis gasométricas (gasometria arterial), gravimétricas (relação peso úmido/peso seco), concentração de proteínas totais no lavado broncoalveolar e histomorfométricas (espessura dos septos alveolares). Os dados obtidos foram submetidos a análise estatística (P < 0,05) RESULTADOS: A pressão parcial de oxigênio ao final do experimento mostrou-se elevada no grupo GS+PTX (460,0 ± 38,2 mmHg) em relação ao grupo GS (336,0 ± 14,6 mmHg) (P < 0,05). No grupo GS, a concentração de proteínas no lavado broncoalveolar encontrou-se aumentada em relação aos demais grupos; no entanto, se mostrou atenuada após a administração de pentoxifilina. Notamos, pela morfologia em todos os grupos avaliados, vasodilatação nos septos alveolares e no grupo S alguns alvéolos apresentaram-se repletos de macrófagos. Estes aspectos foram atenuados no GS+PTX. A espessura dos septos alveolares mostrou uma significante redução no grupo GS+PTX quando comparado com o grupo GS (P < 0,05). CONCLUSÃO: A pentoxifilina restabelece a oxigenação e reduz os efeitos deletérios do processo de sepse em associação à ventilação mecânica com baixo volume corrente.

OBJECTIVE: Respiratory repercussion on acute lung injury in a model of induced sepsis intraperitoneally. METHODS: Fifteen animals taken at random were submitted to adult male Wistar rats. The rats were randomly divided into 3 groups (n=15): Group C - control group received only mechanical ventilation; Group S - rats received live Escherichia coli (E. coli) intraperitoneally (septic) and after 6 hours they were treated with normal saline infusion and ventilated with a low tidal volume. Group S+PTX - rats received live Escherichia coli intraperitoneally (septic) and after 6 hours they were treated with pentoxifylline (PTX) infusion and ventilated with a low tidal volume. All animals were ventilated during 180 minutes. We analyzed the arterial blood gases, gravimetric indices and histomorphometric analysis. RESULTS: Blood gases, wet to dry ratios, and total protein concentrations in the bronchoalveolar lavage were analyzed in all experimental groups. In the end of the experiment the partial pressure of oxygen was higher in the GS+PTX (460,0 ± 38,2 mmHg) compared with GS (336,0 ± 14,6 mmHg). Pentoxifylline with low tidal volume attenuated significantly total protein in the bronchoalveolar lavage. The septal diameter was significantly reduced in the group GS compared with group GS+PTX (P < 0,05). CONCLUSIONS:The pentoxifylline ameliorated the oxygenation and decreased the deleterious effects of sepsis in the associated mechanical ventilation.

Prevalence of acute diarrhoea in Kathmandu valley.

This retrospective study was conducted during January to September in the year 1997. Three hundred and forty nine stool samples were collected from diarrhoea patients from different places of Kathmandu valley and examined at National Public Health Laboratory (NPHL), Teku, Kathmandu. Acute diarrhoea becomes epidemic in rainy season and is a major public health problem of the city. In this study, people with poor hygiene practice and poor education were infected more than other people. Among the 349 patients with the gastrointestinal disease, 26.0% were found to have bacterial infection. Out of which, 88 (25.1%), one (0.28%), one (0.28%), and one (0.28%) were found to be Vibrio cholerae 01, Vibrio cholerae 0139, Shigella dysenteriae and Escherichia coli respectively. Cholera cases were found almost throughout the year in the city though the numbers increased during the rainy season. It was highest during July (34.6%) followed by August (32.35%), September 32% and June (6.89%). The uncommon species of Vibrio i.e. Vibrio cholerae 0139 was also found in the study. Higher prevalence was found in urban areas (83.52%) than in rural areas (16.48%). Antimicrobial susceptibility testing of bacterial isolates showed that Ciprofloxacin (97.85%) was found to be the most effective antibiotic followed by Tetracycline (92.34%), Erythromycin (92.34%), Norfloxacin (93.34%), Cholramphenicol, Ampicillim, but Cotrimoxazole were found to be resistant to all isolated Vibrio cholerae.

Gas-forming urinary tract infection

Emphysematous or gas-forming infections, a very small percentage of bacterial infections of the urinary tract, attract importance because of their life threatening potential. Herein, we report a 60-year-old Saudi female patient who was a known case of Diabetes mellitus for 15 years. She was admitted with left flank pain of 5 days duration, abdominal distension, nausea, vomiting and chills associated with increased frequency of urine, urgency, and dysuria. She had leukocytosis, high blood sugar, elevated urea and creatinine and pyuria. Urine culture grew Escherichia coli. Ultrasound and CT scan showed left pelvicalyceal dilatation and air in the left kidney and urinary bladder. She was treated with a prolonged parenteral antibiotic course, and insulin, with complete recovery

Hemorrhagic Colitis due to Escherichia coli O157 Infection in a Patient with Takayasu's Arteritis / 대한소화기학회지

Escherichia coli (E coli) O157 may cause abdominal pain and diarrhea followed by hematochezia. Most of cases resolve spontaneously after several days. Takayasu's arteritis affects medium- and large-sized arteries, aortic arch and its branch, and rarely affects inferior mesenteric artery. In case of Takayasu's arteritis with hematochezia, we must distinguish among ulcerative colitis, ischemic colitis, and infectious colitis with Takayasu's arteritis. We report a case of 17-year-old woman who suffered from hemorrhagic colitis by E. coli O157, and combined with leg claudication and abdominal pain by Takayasu's arteritis that affected abdominal aorta and inferior mesenteric artery. Sigmoidoscopy showed edematous, hyperemic mucosa and superficial ulcerations in the sigmoid colon. Abdominal CT scan showed diffuse submucosal edema, narrowing of distal abdominal aorta and inferior mesenteric artery. Hematochezia disappeared after the conservative treatment and leg claudication and abdominal pain disappeared after the aortic angioplasty.