Principales agentes etiológicos de las enfermedades diarreicas agudas infantiles en Chimborazo, Ecuador / Main etiological agents of childhood acute diarrheal diseases in Chimborazo, Ecuador

Las enfermedades diarreicas constituyen la principal causa de morbimortalidad en niños menores de cinco años, con alrededor de 1.700 millones de casos y 1,5 millones de muertes por año a nivel mundial. Para el año 2010, en la Sierra de Ecuador se registró un alto porcentaje de infantes fallecidos a causa de enfermedades diarreicas agudas (EDA), incluyendo la provincia de Chimborazo; mientras que, para el año 2016, se registraron en Ecuador 590.523 casos de EDA, siendo más afectados los niños de sectores de mayor pobreza. Se realizó un estudio descriptivo en pacientes pediátricos con episodios diarreicos que acudieron a centros de salud de los cantones rurales de la provincia Chimborazo. Se realizó análisis coprológico y coproparasitológico en 258 muestras; se identificaron bacterias enteropatógenas mediante pruebas bioquímicas y de susceptibilidad antimicrobiana, se realizó diagnóstico parasitológico mediante análisis macroscópico y microscópico y para detección de virus se emplearon pruebas inmunológicas. Se observó un mayor número de casos de EDA en los cantones Alausí (50%) y Chunchi (19%). De los pacientes con EDA, los rotavirus son el principal agente etiológico aislado (24,8%), seguido por Shigella (17,8%); mientras que Giardia intestinalis (8,5%) y Salmonella (10,1%) son los microorganismos que se aislaron con menor frecuencia en las muestras. Los resultados del presente estudio, permiten tener un panorama etiológico de las EDA en la provincia de Chimborazo y contribuir en la vigilancia epidemiológica, ejecución de programas sanitarios y de vacunación, para disminuir la vulnerabilidad de la población infantil ante dichas infecciones(AU)

Diarrheal diseases are the main cause of morbidity and mortality in children under five years of age, with around 1.7 billion cases and 1.5 million deaths per year worldwide. For the year 2010, in the Sierra de Ecuador a high percentage of infants died due to acute diarrheal diseases (ADD), including the province of Chimborazo; while, for the year 2016, 590,523 cases of ADD were registered in Ecuador, with children from the poorest sectors being more affected. A descriptive study was carried out in pediatric patients with diarrheal episodes who attended health centers in the rural cantons of Chimborazo province. Coprological and coproparasitological analysis was performed on 258 samples; Enteropathogenic bacteria were identified by biochemical and antimicrobial susceptibility tests, a parasitological diagnosis was made by macroscopic and microscopic analysis, and immunological tests were used to detect viruses. A greater number of ADD cases was observed in the Alausí (50%) and Chunchi (19%) cantons. Of patients with ADD, rotaviruses are the main etiological agent isolated (24.8%), followed by Shigella (17.8%); while Giardia intestinalis (8.5%) and Salmonella (10.1%) are the microorganisms that were isolated less frequently in the samples. The results of this study allow us to have an etiological panorama of EDA in the province of Chimborazo and contribute to epidemiological surveillance, execution of health and vaccination programs, to reduce the vulnerability of the child population to these infections(AU)

Pathogenic detection and molecular tracing of a bacillary dysentery outbreak by Shigella sonnei in Huainan city / 中华预防医学杂志

Objective: To understand the virulence gene and drug resistance profile of Shigella sonnei outbreak in Huainan city, and conduct pathogenic traceability analysis. Methods: Water samples and feces related to an infectious diarrhea outbreak in Huainan city in August 2020 were collected for multiple pathogen detection. Virulence gene, drug sensitivity, pulse-field gel electrophoresis and whole genome sequencing of Shigella isolates were analyzed respectively. Results: 38 strains of Shigella sonnei were detected in 56 samples of mucilage feces with a positive rate 67.86%, and all serotypes were Shigella sonnei Phase I. Three strains of Shigella sonnei were detected by fluorescence PCR in the Gram-negative (GN) bacterial enrichment solution of terminal water and well water. Virulence genes were ipaH positive (38), ipaH/ial (31) and ipaH/ial/sen positive (1), respectively. The drug resistance spectrum showed that 9 of 14 antibiotics were 100% resistant, and only imipenem, chloramphenicol, ceftazidime and ciprofloxacin were effective drugs. XbaⅠ restriction enzyme map type of 36 isolates was completely consistent, and the ST type analysis of 3 strains was ST152. Whole genome sequencing and analysis verified that the outbreak was caused by a single clonal group of strains, and revealed that the isolates of the outbreak were clustered into a large cluster with 3 Chinese strains and 1 Korean strain in the database, far away from the strains of other countries. Conclusion: The outbreak is caused by a single clone of Shigella sonnei, which are low virulence strains and have multiple drug resistance.

Factores asociados a la diarrea del viajero en Quito, Provincia de Pichincha, Ecuador / Factors associated with traveler's diarrhea in Quito, Pichincha Province, Ecuador

La diarrea del viajero (DV) es la complejidad más común y su repercusión varía en función de muchas variables: edad, lugar de destino, estación del año, tipo de residencia, origen del viajero y, por supuesto, la dieta durante el viaje, en definición es la emisión de heces sueltas tres o más veces al día, se adquiere mayormente al consumir alimentos y bebidas contaminados con patógenos que ocasionen diarrea. A nivel mundial, las causas más comunes de DV son dos patotipos de Escherichia coli (enterotoxigénica y enteroagregativa) y Campylobacter, aunque existen variaciones significativas según el área geográfica visitada. Algunos autores han detectado la presencia de diarrea en más de la mitad de los viajeros a países en vías de desarrollo. Se realizó un estudio descriptivo de corte transversal en 15 hospitales centinelas de la zona 9 del Sistema de Vigilancia de la resistencia antimicrobiana, en la provincia de Pichincha Quito, Ecuador entre enero 2019 a enero 2020, con el objeto de caracterizar los eventos de DV. 517 registros, solo en 298 se asento la procedencia, pudiendo atribuirse a ese 42,34% la procedencia por nacionalidad, se estimó que 108 casos presentaron infección mixta de al menos una bacteria y otro tipo de agresor, lo que representa 36,24%, siendo el agente causal principalmente involucrado ETEC, seguida de E. coli H7:O157 (N=60)(AU)

Traveler's diarrhea (DV) is the most common complexity and its impact varies depending on many variables: age, place of destination, season of the year, type of residence, origin of the traveler and, of course, the diet during the trip, In definition, it is the emission of loose stools three or more times a day, it is acquired mostly by consuming food and beverages contaminated with pathogens that cause diarrhea. Worldwide, the most common causes of DV are two Escherichia coli pathotypes (enterotoxigenic and enteroaggregative) and Campylobacter, although there are significant variations depending on the geographic area visited. Some authors have detected the presence of diarrhea in more than half of the travelers to developing countries. A descriptive cross-sectional study was carried out in 15 sentinel hospitals in zone 9 of the Antimicrobial Resistance Surveillance System, in the province of Pichincha Quito, Ecuador between January 2019 and January 2020, in order to characterize VD events. 517 records, only in 298 the origin was established, and that 42.34% can be attributed the origin by nationality, it was estimated that 108 cases presented mixed infection of at least one bacterium and another type of aggressor, which represents 36.24% , the causative agent being mainly involved ETEC, followed by E. coli H7: O157 (N = 60). Likewise, ETEC is responsible for the greatest severity in clinical pictures, being responsible for 50.00% of the cases in this category(AU)

Miocarditis por gram negativos / Gram-Negative Myocarditis

Resumen Objetivo: describir las características epidemiológicas, clínicas y microbiológicas de los pacientes que cursan con miocarditis por Enterobacterias. Métodos: se realizó una revisión sistemática de la literatura, en la que se incluyeron Pubmed, Ovid, Scopus, SciELO y LILACS sin exclusión por tipo de idioma. La población objetivo de estudio fueron los pacientes con diagnóstico de infección bacteriana por bacilo gram negativo mediante cultivo, técnicas moleculares o histopatología, y quienes presentaban biopsia de miocardio o, en su defecto, resonancia magnética cardiaca con hallazgos sugestivos de miocarditis. Resultados: se encontraron 742 artículos, de los cuales se incluyeron 24; en estos se reportaron 27 pacientes. La edad promedio fue de 31 años. El 81% de los pacientes eran de sexo masculino. El síntoma principal fue diarrea (80%), seguido de fiebre (53%) y dolor torácico (38%). El 37% de los pacientes fallecieron. El hallazgo más común en el electrocardiograma fue la elevación del segmento ST (36,7%). En quienes se realizó ecocardiograma se encontraron anormalidades en 50% de los casos, siendo más frecuente la disminución en la fracción de eyección. El microorganismo más común fue el Campylobacter jejuni, seguido por Salmonela sp. Conclusiones: la miocarditis causada por enterobacterias es más frecuente en pacientes adultos jóvenes de sexo masculino. Los síntomas gastrointestinales suelen estar presentes al momento de la presentación clínica. El diagnóstico requiere de alta sospecha clínica teniendo en cuenta que las anormalidades eléctricas y en ecocardiograma no se encuentran en todos los pacientes.

Abstract Objective: To describe the epidemiological, clinical, and microbiological characteristics of patients with myocarditis due to Enterobacteria. Methods: A systematic review was carried out on the literature, which included Pubmed, Ovid, Scopus, SciELO, and LILACS, with no exclusions due to language. The target population of the study were patients with a diagnosis of bacterial infection due to gram negative bacillus by means of a culture, or using molecular or histopathology technique. They also had to have had a myocardial biopsy or, if not, a cardiac magnetic resonance scan with findings suggestive of myocarditis. Results: Out of a total of 742 articles found, 24 of these, in which 27 patients were described, were included. The mean age was 31 years, and 81% were male. The main symptom was diarrhoea (80%), followed by fever (53%), and chest pain (38%). More than one-third (37%) of the patients died. The most common finding on the electrocardiogram (ECG) was elevation of the ST segment (36.7%). Abnormalities were found in 50% of the cases, on whom a cardiac ultrasound was performed, with a decrease in the ejection fraction being the most common. The most common microorganism was Campylobacter jejuni, followed by Salmonella spp. Conclusions: Myocarditis caused by enterobacteria is most common in young male patients. The gastrointestinal symptoms are usually present from the clinical onset. The diagnosis requires a high clinical suspicion, taking into account that the abnormalities in the ECG and cardiac ultrasound are not found in all patients.

Acute diarrhea with blood: diagnosis and drug treatment / Diarreia aguda com sangue: diagnóstico e tratamento medicamentoso

Abstract Objective To restate the epidemiological importance of Shigella in acute diarrhea with blood, providing an overview of the treatment and stressing the need for the correct indication of antibiotic therapy. Sources of Data A search was carried out in the Medline and Scopus databases, in addition to the World Health Organization scientific documents and guidelines, identifying review articles and original articles considered relevant to substantiate the narrative review. Synthesis of Data Different pathogens have been associated with acute diarrhea with blood; Shigella was the most frequently identified. The manifestations of shigellosis in healthy individuals are usually of moderate intensity and disappear within a few days. There may be progression to overt dysentery with blood and mucus, lower abdominal pain, and tenesmus. Conventional bacterial stool culture is the gold standard for the etiological diagnosis; however, new molecular tests have been developed to allow the physician to initiate targeted antibacterial treatment, addressing a major current concern caused by the increasing resistance of Shigella. Prevention strategies include breastfeeding, hygiene measures, health education, water treatment, and the potential use of vaccines. Conclusions Acute diarrhea is an important cause of mortality in children under 5 years and shigellosis is the leading cause of acute diarrhea with blood worldwide. The current concern is the increase in microbial resistance to the recommended antibiotics, which brings an additional difficulty to therapeutic management. Although no vaccine is yet available against Shigella, several candidates are undergoing clinical trials, and this may be the most cost-effective preventative measure in future.

Resumo Objetivo Reiterar a importância epidemiológica da Shigella na diarreia aguda com sangue, fornecer uma visão geral do tratamento e ressaltar a necessidade da correta indicação da antibioticoterapia. Fontes dos dados Realizada pesquisa nos bancos de dados Medline e Scopus, além de documentos científicos e diretrizes da Organização Mundial da Saúde, com a identificação de artigos de revisão e artigos originais considerados relevantes para fundamentar a revisão do tipo narrativa. Síntese dos dados Diferentes patógenos têm sido associados à diarreia aguda com sangue, a Shigella é o mais frequente. As manifestações da shigelose em indivíduos saudáveis são geralmente de intensidade moderada e desaparecem em poucos dias. Pode haver progressão para disenteria franca com sangue e muco, dor em abdome inferior e tenesmo. A coprocultura bacteriana convencional é o padrão-ouro para o diagnóstico etiológico, porém novos testes moleculares foram desenvolvidos, os quais permitem ao médico iniciar tratamento antibacteriano direcionado, sanar uma grande preocupação atual, devido à crescente resistência da Shigella. Estratégias de prevenção incluem aleitamento, medidas de higiene, educação em saúde, tratamento da água e o potencial uso de vacinas. Conclusões A diarreia aguda é uma importante causa de mortalidade em crianças com menos de cinco anos e a shigelose é a principal causa de diarreia aguda com sangue em todo o mundo. A preocupação atual é o aumento da resistência microbiana aos antibióticos preconizados, o que traz uma dificuldade adicional ao manejo terapêutico. Embora ainda não exista vacina disponível para Shigella, várias candidatas estão em fase de testes clínicos, podem futuramente ser a medida preventiva mais custo-efetiva.

Reverse vaccinology approach for the identification and characterization of outer membrane proteins of Shigella flexneri as potential cellular- and antibody-dependent vaccine candidates

Enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis as a reliable evidence for suspected Shigella spp. outbreaks

Abstract Background Shigellosis remains a serious public health problem and an important cause of morbidity and mortality worldwide. The aim of this study was to characterize fliC and the genetic relatedness of Shigella spp. isolated during a one-year period from children in a suspected outbreak in Tehran, Iran. Methods and results Fifty Shigella spp. were isolated from 3779 stool samples of children with diarrhea (prevalence rate: 1.32%). Among the isolates, 92% were characterized as Shigella sonnei, while 6% and 2% were identified as S. flexneri and S. boydii, respectively. S. dysenteriae was not recovered from the patients. All isolates were negative for fliC except for Shigella standard strains. The enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) profiles allowed differentiating the 50 isolates into 5 ERIC types, which were grouped into five clusters (ET1-ET5). Computer-assisted clustering of the strains showed a high degree of similarity among the isolates. Conclusion In conclusion, given the clonal correlation of the Shigella strains isolated in this study and the lack of fliC among them, we propose that probably a single or limited fliC-defected Shigella clone spread and caused the outbreak.

Genotypic Diversity of Multidrug Resistant Shigella species from Iran

BACKGROUND: In many developing countries, shigellosis is endemic and also occurs in epidemics and treatment of multidrug-resistant (MDR) isolates are important. The aims of this study were to determine the antimicrobial susceptibility, prevalence of class 1 and 2 integrons and the clonal relatedness of isolates. MATERIALS AND METHODS: Antimicrobial susceptibility tests were performed by disc diffusion method. Polymerase chain reaction (PCR)-sequencing technique was employed for detection and characterization of integrons. The genetic relatedness was evaluated by using enterobacterial repetitive intergenic consensus (ERIC) PCR. RESULTS: There was a high percentage of resistance to trimethoprim-sulfamethoxazole (TMP/SMX) (93.7%), ampicillin (AMP) (87.3%), streptomycin (STR) (84.5%) and tetracycline (TET) (78.9%). Multidrug resistant phenotype was seen in 95.1% of total isolates. Most common MDR profile was TMP/SMX/STR/AMP resistant pattern. Among the 142 Shigella spp. analyzed in this study, 28 isolates were positive for class 1 integron with two types of gene cassette arrays (dfrA17/aadA5 = 31.7% and dfrA7 = 3.8%). The class 2 integron was more frequently detected among the isolates (94.7%) with dfrA1/sat1/aadA1 (69.4%) and dfrA1/sat1 (30.6%) gene cassettes. ERIC-PCR results showed 6, 5, 4 and 3 main genotypes among S. flexneri, S. sonnei, S. boydii and S. dysenteriae isolates, respectively. CONCLUSIONS: Our findings revealed that multidrug resistant Shigella species with high prevalence of class 2 integron were very common in Iran. In addition, ERIC-PCR patterns showed limited variety of clones are responsible for shigellosis in the region of the study.

Genotypic Diversity of Multidrug Resistant Shigella species from Iran

BACKGROUND: In many developing countries, shigellosis is endemic and also occurs in epidemics and treatment of multidrug-resistant (MDR) isolates are important. The aims of this study were to determine the antimicrobial susceptibility, prevalence of class 1 and 2 integrons and the clonal relatedness of isolates. MATERIALS AND METHODS: Antimicrobial susceptibility tests were performed by disc diffusion method. Polymerase chain reaction (PCR)-sequencing technique was employed for detection and characterization of integrons. The genetic relatedness was evaluated by using enterobacterial repetitive intergenic consensus (ERIC) PCR. RESULTS: There was a high percentage of resistance to trimethoprim-sulfamethoxazole (TMP/SMX) (93.7%), ampicillin (AMP) (87.3%), streptomycin (STR) (84.5%) and tetracycline (TET) (78.9%). Multidrug resistant phenotype was seen in 95.1% of total isolates. Most common MDR profile was TMP/SMX/STR/AMP resistant pattern. Among the 142 Shigella spp. analyzed in this study, 28 isolates were positive for class 1 integron with two types of gene cassette arrays (dfrA17/aadA5 = 31.7% and dfrA7 = 3.8%). The class 2 integron was more frequently detected among the isolates (94.7%) with dfrA1/sat1/aadA1 (69.4%) and dfrA1/sat1 (30.6%) gene cassettes. ERIC-PCR results showed 6, 5, 4 and 3 main genotypes among S. flexneri, S. sonnei, S. boydii and S. dysenteriae isolates, respectively. CONCLUSIONS: Our findings revealed that multidrug resistant Shigella species with high prevalence of class 2 integron were very common in Iran. In addition, ERIC-PCR patterns showed limited variety of clones are responsible for shigellosis in the region of the study.

Multiplex PCR Based Epidemiological Study for the Causes of Acute Diarrheal Disease in Adults Living in Jeju Island / 대한임상미생물학회지

BACKGROUND: We attempted to determine the characteristics of diarrheal pathogens according to species, seasonal variations, and patient age using multiplex PCR for the epidemiologic study of diarrheal disease in Jeju Island. METHODS: From March 2015 to Feb 2017, stool specimens were collected from 537 diarrheal patients older than 16 years. Multiplex PCR was used to identify pathogens and found Group A Rotavirus, enteric Adenovirus, Norovirus GI/GII, Astrovirus, Salmonella spp., Shigella spp., Vibrio spp., Campylobacter spp., Clostridium difficile toxin B (CDB), Clostridium perfringens, Yersinia enterocolitica, Aeromonas spp., Escherichia coli O157:H7, and verocytotoxin-producing E. coli (VTEC). RESULTS: Pathogens were isolated from 221 of 537 samples (41.2%); 9.3% were positive only for viral pathogens; 30.2%, only for bacterial pathogens; and 1.7%, for both viral and bacterial pathogens. Bacteria were more prevalent in spring, summer, and autumn, but viral pathogens were more prevalent in winter. Overall prevalence were Campylobacter spp. (26.7%), Clostridium perfringens (23.9%); Norovirus GII (11.4%), CDB (8.2%), Aeromonas spp. (6.3%), Group A Rotavirus (5.1%), Salmonella spp. (3.9%), Astrovirus (3.9%), Norovirus GI (3.1%), Vibrio spp (2.7%), enteric Adenovirus (1.6%), Shigella spp. (1.2%), VTEC (1.2%), and Yersinia enterocolitica (0.4%). Group A Rotavirus and Norovirus GII were more prevalent in winter and early spring. Campylobacter spp., CDB, and C. perfringens were detected frequently, without seasonal variation. CONCLUSION: Bacterial pathogens are more prevalent than viruses in acute diarrhea in adults living in Jeju Island, especially in spring, summer, and autumn. Viral pathogens are prevalent in winter. Campylobacter spp., CDB, and Clostridium perfringens are the major pathogens occurring without seasonal variations. These data will be helpful in identifying diarrheal pathogens and for treatments and prevention strategies.

Isolamento e determinação de sensibilidade e resistência a antimicrobianos de cepas bacterianas presentes na cloaca de Trachemys scripta elegans (Wied, 1839) criadas em cativeiro em Petrolina, PE / Isolation and determination of antimicrobials sensitivity and resistance of bacterial strains present in the cloaca Trachemys scripta elegans (Wied, 1839) raised in captivity in Petrolina/PE, Brazil

Este estudo isolou e determinou o perfil de sensibilidade e de resistência a antimicrobianos de cepas bacterianas isoladas da cloaca de Trachemys scripta elegans (T. s. elegans) criadas em cativeiro. Após 120 dias de adaptação, amostras de swab cloacal obtidas de 20 animais adultos foram cultivadas e, após a identificação dos patógenos através de testes bioquímicos, submetidas ao teste de suscetibilidade a nove antimicrobianos. Enterobacter aerogenes (85%); Shigella spp. (10%) e Edwadsiella spp. (5%) foram isolados e identificados. Os isolados de E. aerogenes foram sensíveis à gentamicina (86%), enrofloxacina (79%), estreptomicina (50%), sulfazotrim (36%) e ampicilina (29%) e resistentes a penicilina (100%), eritromicina (93%), cefalexina (86%) ampicilina (71%) e sulfazotrim (64%). Isolados de Shigella spp. apresentaram sensibilidade à gentamicina (100%), enrofloxacina (50%), doxicilina (50%), estreptomicina (50%), ampicilina (50%), penicilina (50%) e sulfazotrim (50%) e resistência a doxicilina (50%), estreptomicina (50%), ampicilina (50%), penicilina (100%), cefalexina (50%) e sulfazotrim (50%), enquanto que os de Edwardsiella spp. foram sensíveis apenas à gentamicina (100%) e altamente resistentes (100%) aos demais antimicrobianos. Os resultados sugerem a participação de T. s. elegans na cadeia epidemiológica, como reservatório de patógenos importantes, como E. aerogenes, Shigella spp. e Edwardisiella spp., tornando importante a adoção de medidas preventivas pelo risco zoonótico que apresentam e corretas de tratamento e de controle em cativeiros e domicílios, assim como de estudos que enfoquem as características de sensibilidade e de resistência antimicrobiana dos isolados cloacais, pois a multirresistência a drogas pode ser transmitida aos humanos e comprometer o tratamento de indivíduos com doenças graves.(AU)

This study isolated and determined the profile of susceptibility and antimicrobials resistance of bacterial strains isolated from the cloaca Trachemys scripta elegans (T. s. elegans) raised in captivity. After 120 days of adaptation, cloacal swab samples obtained from 20 adults animals were grown and, after the pathogens identification through biochemical tests, submitted to the test of susceptibility to nine antimicrobials. Enterobacter aerogenes (85%); Shigella spp. (10%) and Edwadsiella spp. (5%) were isolated and identified. Isolates from E. aerogenes were sensitive to gentamicin (86%), enrofloxacin (79%), streptomycin (50%), sulfazotrim (36%) and ampicillin (29%) and resistant to penicillin (100%), erythromycin (93%), cephalexin (86%), ampicillin (71%) and sulfazotrim (64%). Isolates from Shigella spp. showed sensitivity to gentamicin (100%), enrofloxacin (50%), doxycycline (50%), streptomycin (50%), ampicillin (50%), penicillin (50%) and sulfazotrim (50%) and resistance to doxycycline (50 %), streptomycin (50%), ampicillin (50%), penicillin (100%), cephalexin (50%) and sulfazotrim (50%), while the Edwardsiella spp. were sensitive only to gentamicin (100%) and were highly resistant (100%) to other antibiotics. The results suggest the participation of T. s. elegans in the epidemiological chain, as reservoir of important pathogens, such as E. aerogenes, Shigella spp. and Edwardisiella spp., making it important to adopt preventive measures for zoonotic risk that present and correct treatment and control in captivity and households, as well as studies that address the sensitivity characteristics and antimicrobial resistance of isolates from cloaca, as it multidrug resistance to drugs can be transmitted to humans and compromise the treatment of patients with serious diseases.(AU)

Shigella sp: um problema de saúde pública / Shigella sp: a public health problem

O aumento do consumo de refeições fora de casa está associado ao aumento das Doenças Veiculadas por Alimentos (DVA), que são provenientes do consumo de alimentos e água contaminados, principalmente, devido à falta de higiene no preparo dos alimentos e à ausência, em muitos casos, do tratamento da água usada no preparo destes alimentos. A shigelose é uma DVA que se caracteriza como uma doença inflamatória do trato gastrointestinal causada pela Shigella cujos sintomas e características se assemelham à salmonelose. O gênero Shigella possui quatro espécies: S. dysenteriae, S. flexneri, S. boydii e S. sonnei. Para a realização deste trabalho foi realizado levantamento de artigos publicados em revistas científicas sobre o tema, com o objetivo de verificar a incidência de Shigella em alimentos abordando suas características e danos provocados à saúde.(AU)

Prevalencia de bacterias enteropatógenas en niños que asisten a un hospital pediátrico en Resistencia, Chaco, Argentina / Prevalence of enteropathogenic bacteria in children attending a pediatric hospital in Resistencia, Chaco, Argentina

La enfermedad diarreica aguda continúa siendo uno de los problemas de salud pública más serios en los países en desarrollo, en los que constituye una de las causas principales de enfermedad y muerte en los niños menores de 5 años. Su epidemiología es totalmente dependiente de la región geográfica, nivel socio económico, costumbres y hábitos de la población.El objetivo del presente trabajo fue determinar la prevalencia de agentes etiológicos bacterianos causantes de diarrea aguda, en niños atendidos en un Hospital Pediátrico de Resistencia, Chaco, en el año 2013.Se investigó la presencia de Shigella spp., Salmonella spp., Campylobacte rspp., Escherichia coli O157:H7 en muestras de materia fecal de niños con enfermedad diarreica aguda. Sobre 823 muestras de materia fecal analizadas en el período mencionado, 93 resultaron positivas para alguno de los enteropatógenos estudiados (Tasa de recuperación del 11,3%).Las frecuencias de aislamiento de los enteropatógenos fueron: Shigella spp (82,8%), Salmonella spp (9,7%), Campylobacter spp (6,5%), y E. coli O157:H7 (1%).Con respecto a las especies, dentro del género Shigella predominó S. flexneri (60/77) seguida de S. sonnei (13/77) y S. boydii (4/77). Con excepción de E. coli O157, en el presente trabajo no se estudiaron los diferentes tipos patogénicos.Como en el resto del país, S. flexneri continúa siendo el agente etiológico más frecuentemente aislado. Este es el primer informe sobre la presencia de Campylobacter en coprocultivos en la provincia del Chaco.

Acute diarrheal disease remains one of the most serious problems of public health in developing countries, which is one of the leading causes of illness and death in children under 5 years. Its epidemiology is totally dependent on the geographic region, socioeconomic status, customs and habits of the population.The aim of this study was to determine the prevalence of bacterial etiologic agents causing acute diarrhea in children attending a Pediatric Hospital in the city of Resistencia, Chaco, during 2013.In this work Shigella spp, Salmonella sp, Campylobacter spp, Escherichia coli O157:H7 were investigatedAmong 823 stool samples analyzed, 93 were positive for any of the enteropathogens studied (recovery rate 11.3%).The frequency of isolation of enteric pathogens were: Shigella spp (82.8%), Salmonella spp (9.7%), Campylobacter spp (6.5%), and E. coli O157: H7 (1%).Respect to genus Shigella, Shigella flexneri was the prevalent (60/77) followed by S. sonnei (13/77) and S. boydii (4/77). With the exception of E. coli O157 in the present work the other pathogenic types were not studied.As in the rest of the country, S. flexneri remains the most frequently isolated etiologic agent. This is the first report about the presence of Campylobacter in stool cultures in the province of Chaco

Genome Sequencing Analysis of Atypical Shigella flexneri Isolated in Korea

OBJECTIVES: An atypical Shigella flexneri strain with a plural agglutination pattern [i.e., reacting not only with serum samples containing type antigen II but also with serum samples containing group antigens (3)4 and 7(8)] was selected for genome sequencing, with the aim of obtaining additional comparative information about such strains. METHODS: The genomic DNA of atypical S. flexneri strain NCCP 15744 was sequenced using an Ion Torrent PGM sequencing machine (Life Technologies, USA). The raw sequence data were preprocessed and reference-assembled in the CLC Assembly Cell software (version 4.0.6; CLC bio, USA). RESULTS: Ion Torrent sequencing produced 1,450,025 single reads with an average length of 144 bp, totaling ~209 Mbp. The NCCP 15744 genome is composed of one chromosome and four plasmids and contains a gtrX gene. Among the published genome sequences of S. flexneri strains, including 2457T, Sf301, and 2002017, strain NCCP 15744 showed high similarity with strain 2002017. The differences between NCCP 15744 and 2002017 are as follows: i) NCCP 15744 carries four plasmids whereas 2002017 carries five; ii) 19 genes (including CI, CII, and cro) were lost in the SHI-O genomic island of NCCP 15744 and six genes were gained as compared with strain 2002017. CONCLUSION: Strain NCCP 15744 is genetically similar to 2002017, but these two strains have different multilocus sequence types and serotypes. The exact reason is unclear, but the 19 lost genes may be responsible for the atypical seroconversion of strain NCCP 15744.

Profiling of Virulence-associated Factors in Shigella Species Isolated from Acute Pediatric Diarrheal Samples in Tehran, Iran

OBJECTIVES: The genus Shigella comprises the most infectious and diarrheagenic bacteria causing severe diseases, mostly in children under five years of age. This study aimed to detect nine virulence genes (ipaBCD, VirA, sen, set1A, set1B, ial, ipaH, stx, and sat) in Shigella species (spp.) using multiplex polymerase chain reaction (MPCR) and to determine the relation of Shigella spp. from pediatric diarrheal samples with hospitalization and bloody diarrhea in Tehran, Iran. METHODS: Shigella spp. were isolated and identified using standard microbiological and serological methods. The virulence genes were detected using MPCR. RESULTS: Seventy-five Shigella spp. (40 S. sonnei, 33 S. flexneri, 1 S. dysenteriae, and 1 S. boydii) were isolated in this study. The prevalence of ial, sen, sat, set1A, and set1B was 74.7%, 45.4%, 28%, 24%, and 24%, respectively. All S. flexneri isolates, while no S. sonnei, S. dysenteriae, or S. boydii isolates, contained sat, set1A, and set1B. All isolates were positive for ipaH, ipaBCD, and virA, while one (1.4%) of the isolates contained stx. The highest prevalence of virulence determinants was found in S. flexneri serotype IIa. Nineteen (57.6%) of 33 S. flexneri isolates were positive for ipaBCD, ipaH, virA, ial, and sat. The sen determinants were found to be statistically significantly associated with hospitalization and bloody diarrhea (p = 0.001). CONCLUSION: This study revealed a high prevalence of enterotoxin genes in S. flexneri, especially in serotype 2a, and has presented relations between a few clinical features of shigellosis and numerous virulence determinants of clinical isolates of Shigella spp.

Clinical Characteristics and Ultrasonographic Findings of Acute Bacterial Enterocolitis in Children / 대한소아소화기영양학회지

PURPOSE: This study clarified the bacterial pathogens currently causing acute infectious enterocolitis (AIE) in children and evaluated the clinical characteristics and ultrasonographic findings according to the different pathogens. METHODS: Medical records regarding age, sex, clinical symptoms, laboratory data, identified enteropathogens, ultrasonographic findings, treatment, and outcome of 34 patients who were diagnosed with AIE via stool examination using multiplex polymerase chain reaction (PCR) or culture, were retrospectively reviewed. RESULTS: Twenty-four patients (70.6%) were male. The mean age of the patients was 8.5±6.2 (range, 1.1–17.1) years. Six bacterial pathogens were isolated: Salmonella species (spp.) (32.4%), Campylobacter spp. (20.6%), verotoxin-producing Escherichia coli (14.7%), Staphylococcus aureus (11.8%), Clostridium difficile (8.8%), and Shigella spp. (2.9%). Abdominal pain occurred in all patients regardless of pathogen. The patients infected with Salmonella were older than those infected with verotoxin-producing E. coli (p<0.05). C-reactive protein levels were higher in patients with Salmonella and Campylobacter infections than in those with verotoxin-producing E. coli infection (p<0.05), the other clinical and laboratory data were indistinguishable between pathogens. Ultrasonography demonstrated diverse involvement of bowel segments according to pathogen. Wall thickening of both the ileum and the entire colon was the most common lesion site regardless of pathogen. CONCLUSION: Various bacterial agents cause AIE and the symptoms are diverse symptoms, however, all most children recovered spontaneously. Use of multiplex PCR on stool samples warrants improvement of its sensitivity for diagnosis of enteropathogenic bacteria. Ultrasonographic examination is useful for diagnosis of AIE; it can also detect the disease extent and severity.

High Frequency of Enteric Protozoan, Viral, and Bacterial Potential Pathogens in Community-Acquired Acute Diarrheal Episodes: Evidence Based on Results of Luminex Gastrointestinal Pathogen Panel Assay

Infectious diarrhea is endemic in most developing countries. We aimed to investigate the protozoan, viral, and bacterial causes of acute diarrhea in Taif, Saudi Arabia. A cross-sectional prospective 1-year study was conducted on 163 diarrheal patients of various ages. Stool samples were collected, 1 per patient, and tested for 3 protozoa, 3 viruses, and 9 bacteria with the Luminex Gastrointestinal Pathogen Panel. Overall, 53.4% (87/163) of samples were positives (20.8% protozoa, 19.6% viruses, 2.8% bacteria, and 9.8% mixed). Rotavirus (19.6%), Giardia duodenalis (16.5%), and Cryptosporidium spp. (8.5%) were the mostly detected pathogens. Adenovirus 40/41 (4.2%), Salmonella (3%), Shiga toxin-producing Escherichia coli (3%), and Entamoeba histolytica (2.4%) were also detected. Norovirus GI/II, Vibrio cholerae, Yersinia enterocolitica, and Clostridium difficile toxin A/B were not detected in any patients. All pathogens were involved in coinfections except E. histolytica. Giardia (5.5%) and rotavirus (3%) were the most commonly detected in co-infections. Enterotoxigenic E. coli (2.4%), Campylobacter spp. (2.4%), E. coli 0157 (1.8%), and Shigella spp. (1.2%) were detected in patients only as co-infections. Infections were more in children 0–4 years, less in adults 40 years, with statistically significant differences in risk across age groups observed with rotavirus (P < 0.001), Giardia (P=0.006), and Cryptosporidium (P=0.036) infections. Lastly, infections were not significantly more in the spring. This report demonstrates the high burden of various enteropathogens in the setting. Further studies are needed to define the impact of these findings on the clinical course of the disease.

Intestinal Parasitic Infections and Environmental Water Contamination in a Rural Village of Northern Lao PDR

A field survey studying intestinal parasites in humans and microbial pathogen contamination at environment was performed in a Laotian rural village to identify potential risks for disease outbreaks. A parasitological investigation was conducted in Ban Lak Sip village, Luang Prabang, Lao PDR involving fecal samples from 305 inhabitants as well as water samples taken from 3 sites of the local stream. Water analysis indicated the presence of several enteric pathogens, i.e., Aeromonas spp., Vibrio spp., E. coli H7, E. coli O157: H7, verocytotoxin-producing E. coli (VTEC), Shigella spp., and enteric adenovirus. The level of microbial pathogens contamination was associated with human activity, with greater levels of contamination found at the downstream site compared to the site at the village and upstream, respectively. Regarding intestinal parasites, the prevalence of helminth and protozoan infections were 68.9% and 27.2%, respectively. Eight helminth taxa were identified in fecal samples, i.e., 2 tapeworm species (Taenia sp. and Hymenolepis diminuta), 1 trematode (Opisthorchis sp.), and 5 nematodes (Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, trichostrongylids, and hookworms). Six species of intestinal protists were identified, i.e., Blastocystis hominis, Cyclospora spp., Endolimax nana, Entamoeba histolytica/E. dispar, Entamoeba coli, and Giardia lamblia. Questionnaires and interviews were also conducted to determine risk factors of infection. These analyses together with a prevailing infection level suggested that most of villagers were exposed to parasites in a similar degree due to limited socio-economic differences and sharing of similar practices. Limited access to effective public health facilities is also a significant contributing factor.

Characterization of Extended-Spectrum β-Lactamase Genes of Shigella flexneri Isolates With Fosfomycin Resistance From Patients in China

BACKGROUND: The emergence of fosfomycin resistance and extended-spectrum β-lactamase (ESBL) genes is a serious threat to public health and a new challenge in shigellosis treatment. The purpose of this study was to identify fosfomycin resistance and characterize β-lactamase genes in fos-carrying isolates of Shigella flexneri from patients in China. METHODS: A total of 263 S. flexneri isolates were collected from 34 hospitals in the Anhui Province of China during September 2012-September 2015 and screened for fosA3, fosA, and fosC2 by PCR amplification and sequencing. The fos-carrying isolates were then screened for β-lactamase genes. The clonal relationships between fosA3-carrying isolates, the transmissibility of fosfomycin resistance, replicon types of plasmids carrying fosfomycin resistance genes and other associated resistance genes were investigated. RESULTS: Twenty-five of the 263 isolates (9.5%) showed resistance to fosfomycin, and 18 (6.8%) were positive for fosA3. None of the isolates was positive for fosA or fosC2. Seventeen of the isolates carrying fosA3 (94%) were CTX-M producers (seven CTX-M-55, five CTX-M-14, and five CTX-M-123), while three (16.7%) were TEM producers (TEM-1).Sixteen (88.9%) fosA3-carrying isolates exhibited multi-drug resistance. The replicon types of the 13 fosA3-carrying plasmids were IncF (n=13), IncHI2 (n=3), IncIl-Ir (n=2), and IncN (n=1). CONCLUSIONS: Our results indicated that fosA3 could spread through plasmids in S. flexneri isolates, along with the bla(CTX-M) and bla(TEM), which facilitate its quick dispersal. To the best of our knowledge, this is the first report of CTX-M-123-type ESBLs in S. flexneri isolates from patients in China.