Fatal case of hemolytic-uremic syndrome in an adult due to a rare serogroup O91 Entero hemorrhagic Escherichia coli associated with a Clostridium difficile infection. More than meets the eye

AbstractHemolytic-uremic syndrome due to enterohemorrhagic Escherichia coli, belonging to serogroup O91 has rarely been described. We report here a case of post-diarrheal HUS due to EHEC O91 in an elderly patient for whom diagnosis was delayed given a previously diagnosed C. difficile infection. This case highlights the usefulness of Shiga-toxin detection

Travel- and Community-Based Transmission of Multidrug-Resistant Shigella sonnei Lineage among International Orthodox Jewish Communities

Shigellae are sensitive indicator species for studying trends in the international transmission of antimicrobial-resistant Enterobacteriaceae. Orthodox Jewish communities (OJCs) are a known risk group for shigellosis; Shigella sonnei is cyclically epidemic in OJCs in Israel, and sporadic outbreaks occur in OJCs elsewhere. We generated whole-genome sequences for 437 isolates of S. sonnei from OJCs and non-OJCs collected over 22 years in Europe (the United Kingdom, France, and Belgium), the United States, Canada, and Israel and analyzed these within a known global genomic context. Through phylogenetic and genomic analysis, we showed that strains from outbreaks in OJCs outside of Israel are distinct from strains in the general population and relate to a single multidrug-resistant sublineage of S. sonnei that prevails in Israel. Further Bayesian phylogenetic analysis showed that this strain emerged approximately 30 years ago, demonstrating the speed at which antimicrobial drug–resistant pathogens can spread widely through geographically dispersed, but internationally connected, communities

Comparative Genomics of Recent Shiga Toxin-Producing Escherichia coli O104:H4: Short-Term Evolution of an Emerging Pathogen

The large outbreak of diarrhea and hemolytic uremic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli O104:H4 in Europe from May to July 2011 highlighted the potential of a rarely identified E. coli serogroup to cause severe disease. Prior to the outbreak, there were very few reports of disease caused by this pathogen and thus little known of its diversity and evolution. The identification of cases of HUS caused by E. coli O104:H4 in France and Turkey after the outbreak and with no clear epidemiological links raises questions about whether these sporadic cases are derived from the outbreak. Here, we report genome sequences of five independent isolates from these cases and results of a comparative analysis with historical and 2011 outbreak isolates. These analyses revealed that the five isolates are not derived from the outbreak strain; however, they are more closely related to the outbreak strain and each other than to isolates identified prior to the 2011 outbreak. Over the short time scale represented by these closely related organisms, the majority of genome variation is found within their mobile genetic elements: none of the nine O104:H4 isolates compared here contain the same set of plasmids, and their prophages and genomic islands also differ. Moreover, the presence of closely related HUS-associated E. coli O104:H4 isolates supports the contention that fully virulent O104:H4 isolates are widespread and emphasizes the possibility of future food-borne E. coli O104:H4 outbreaks

Species-wide whole genome sequencing reveals historical global spread and recent local persistence in Shigella flexneri.

Shigella flexneri is the most common cause of bacterial dysentery in low-income countries. Despite this, S. flexneri remains largely unexplored from a genomic standpoint and is still described using a vocabulary based on serotyping reactions developed over half-a-century ago. Here we combine whole genome sequencing with geographical and temporal data to examine the natural history of the species. Our analysis subdivides S. flexneri into seven phylogenetic groups (PGs); each containing two-or-more serotypes and characterised by distinct virulence gene complement and geographic range. Within the S. flexneri PGs we identify geographically restricted sub-lineages that appear to have persistently colonised regions for many decades to over 100 years. Although we found abundant evidence of antimicrobial resistance (AMR) determinant acquisition, our dataset shows no evidence of subsequent intercontinental spread of antimicrobial resistant strains. The pattern of colonisation and AMR gene acquisition suggest that S. flexneri has a distinct life-cycle involving local persistence

Les Escherichia coli entérohémorragiques : des entérobactéries d’actualité

International audienceSince the 1980s, EnterohaemorrhagicEscherichia coli (EHEC) have been recognised as emergent pathogens causing foodborne outbreaks. The latest one is the E. coli O104:H4 outbreak which occurred in Germany in May 2011 then in France.In France, the surveillance of EHEC infections is based on surveillance of hemolytic-uremic syndrome (HUS) in children under 15 years old. The average annual incidence is 0.8/100,000 children under 15 years old with a predominance of the O157:H7 serotype.EHEC are one of the six clinical pathovars of E. coli defined by their capacity to produce Shiga-toxins and for that reason, are part of a larger group called: Shigatoxin-producingE. coli (STEC).EHEC are a cause of different troubles ranging from mild diarrhea to haemorrhagic colitis which might be complicated by HUS in young children and thrombocytopenic thrombotic purpura in adults.The reservoir of EHEC is mainly the intestinal tract of ruminants: EHEC are transmitted via ingestion of contaminated food or water, person-to-person contact, direct animal contact and exposure to the environment.The diagnosis of the EHEC infections relies on isolation of STEC in stool samples or detection of genes encoding for Shiga-toxins.Treatment is mainly symptomatic. Use of antibiotics is controversial because the risk of HUS could be increased (release of toxins).Les Escherichia colientérohémorragiques (EHEC) sont considérés depuis les années 1980 comme des pathogènes émergents responsables d’épidémies d’origine alimentaire (la plus récente est celle due à E. coli O104:H4 en mai 2011, en Allemagne puis en France).En France, la surveillance des infections à EHEC repose sur la surveillance des SHU chez les enfants de moins de 15 ans. L’incidence annuelle est de 0,8/100 000 enfants de moins de 15 ans avec prédominance du sérotype O157:H7.Les EHEC constituent l’un des six pathovars définis de l’espèce E. coli caractérisés par leur capacité à produire des cytotoxines de la famille des Shiga-toxines et font partie d’un groupe plus important que l’on appelle les Shiga toxin-producing E. coli (STEC).Les EHEC sont responsables chez l’homme de troubles variés allant d’une simple diarrhée aqueuse bénigne à une colite hémorragique pouvant évoluer vers des formes graves telles que le syndrome hémolytique et urémique (SHU) chez les jeunes enfants et le purpura thrombotique thrombocytopénique chez l’adulte.Le réservoir de ces bactéries est majoritairement le tube digestif des ruminants : la transmission à l’homme se fait principalement par la consommation d’aliments insuffisamment cuits (viande de bœuf notamment), l’eau contaminée, le contact direct avec des animaux ou avec des personnes infectées.Le diagnostic de certitude des infections à EHEC est basé sur la mise en évidence dans les selles, des gènes de virulence et/ou de souches productrices de Shiga-toxines.Le traitement est principalement symptomatique, les antibiotiques étant très controversés car ils favoriseraient le SHU par libération des toxines

Evaluation of CHROMagar STEC and STEC O104 chromogenic agar media for detection of Shiga toxin-producing Escherichia coli in stool

The performance of CHROMagar STEC and CHROMagar STEC O104 (CHROMagar Microbiology, Paris, France) media for the detection of Shiga toxin-producing Escherichia coli (STEC) was assessed with 329 stool specimens collected over 14 months from patients with suspected STEC infections (June 2011 to August 2012). The CHROMagar STEC medium, after an enrichment broth step, allowed the recovery of the STEC strain from 32 of the 39 (82.1%) Shiga toxin-positive stool specimens, whereas the standard procedure involving Drigalski agar allowed the recovery of only three additional STEC strains. The isolates that grew on CHROMagar STEC medium belonged to 15 serotypes, including the prevalent non-sorbitol-fermenting (NSF) O157:H7, O26: H11, and O104:H4 serotypes. The sensitivity, specificity, and positive and negative predictive values for the CHROMagar STEC medium were between 89.1% and 91.4%, 83.7% and 86.7%, 40% and 51.3%, and 98% and 98.8%, respectively, depending on whether or not stx-negative eae-positive E. coli was considered atypical enteropathogenic E. coli (EPEC) or STEC that had lost Shiga toxin genes during infection. In conclusion, the good performance of CHROMagar STEC agar medium, in particular, the high negative predictive value, and its capacity to identify NSF O157:H7 as well as common non-O157 STEC may be useful for clinical bacteriology, public health, and reference laboratories; it could be used in addition to a method targeting Shiga toxins (detection of stx genes by PCR, immunodetection of Shiga toxins in stool specimens, or Vero cell cytotoxicity assay) as an alternative to O157 culture medium. This combined approach should allow rapid visualization of both putative O157 and non-O157 STEC colonies for subsequent characterization, essential for real-time surveillance of STEC infections and investigations of outbreaks. C ertain strains of Shiga toxin-producing Escherichia coli (STEC) are important causes of food-borne disease in industrialized countries. The clinical manifestations of STEC infections range from mild diarrhea to severe and specific complications, such as hemolytic-uremic syndrome (HUS), which occurs primarily in young children (1, 2). These STEC strains associated with human infections are also called enterohemorrhagic E. coli (EHEC). Animals, and especially cattle, serve as reservoirs for STEC. Transmission occurs via ingestion of contaminated food or water, person-to-person contact, direct animal contact, and exposure to the environment. STEC strains are characterized by their ability to produce toxins related to those of Shigella dysenteriae type 1 (3): two types have been described among STEC isolates, Shiga toxin 1 and Shiga toxin 2, respectively, encoded by the stx 1 and stx 2 genes carried on temperate bacteriophages (4, 5). Most STEC isolates also carry the chromosomally located locus of enterocyte effacement (LEE), a pathogenicity island, first described in enteropathogenic E. coli (EPEC). LEE promotes the development of attaching-and-effacing lesions in the host intestinal mucosa cells (6). One of the LEE genes, eae (for EPEC attaching and effacing), encodes intimin, an outer membrane adhesin essential for the intimate attachment of the bacteria to enterocytes. Other adherence and colonization factors, such as adhesins and pili, are present in LEE-negative STEC strains. The STEC O104:H4 strain responsible for a large outbreak of HUS in Germany and other European countries in 2011 displays a characteristic aggregative adhesion (AA) pattern caused by an enteroaggregative E. coli (EAEC) genetic background (7-11). The laboratory identification of STEC requires screening for Shiga toxin genes or proteins in stool specimens, followed by culture, serotyping, and confirmation of the presence of the virulence genes (at least stx 1 and stx 2 and then eae and aggR) in isolated colonies. Since the first reported STEC outbreak in 1982 (12), various methods for the detection of STEC, especially E. coli O157: H7, which is the most prevalent group of STEC, have been developed (13). STEC O157:H7 had been found to be non-sorbitol fermenting (NSF), and consequently, culture media containing sorbitol have been marketed and widely used. However, the identification of sorbitol-fermenting (SF) STEC O157:H7 (SF O157) strains, mainly in Germany (14-16), and the general increase of non-O157 STEC (generally SF) strains in clinical practic

CTX-M-55-type ESBL-producing Salmonella enterica are emerging among retail meats in Phnom Penh, Cambodia

Members of the BIRDY study group : Bodonirina Tanjona Raheliarivao, Frédérique Randrianirina, Perlinot Herindrainy, Zafitsara Zo Andrianirina, Feno Manitra Jacob Rakotoarimanana, Benoit Garin, Jean-Marc Collard, Agathe de Lauzanne, Laurence Borand, Patrice Piola, Alexandra Kerléguer, Thida Chon, Sok Touch, Arnaud Tarantola, Sophie Goyet, Siyin Lach, Veronique Ngo, Muriel Vray, Marguerite Diatta, Joseph Faye, Abibatou Ndiaye, Vincent Richard, Abdoulaye Seck, Raymond Bercion, Amy Gassama Sow, Jean Baptiste Diouf, Pape Samba Dieye, Balla Sy, Bouya Ndao, Didier Guillemot, Bich-tram Huynh, Maud Seguy, Laurence Watier, Abdou Armya Youssouf and Michael Padget.International audienceBACKGROUND:Salmonella enterica is a leading cause of human gastroenteritis. S. enterica strains that produce ESBLs (ESBL-Salm) remain rare in Europe and North America, but less is known about their prevalence among animal-derived foods in countries with weaker food safety practices and unregulated veterinary antibiotic use.OBJECTIVES:To examine the prevalence and characteristics of ESBL-Salm from retail meats in Phnom Penh, Cambodia.METHODS:We tested fish, pork and chicken from two markets for ESBL- and carbapenemase-producing Salmonella from September-December 2016, using cefotaxime- and ertapenem-supplemented media, respectively. ESBL-Salm were sequenced and their genomes characterized. We performed plasmid conjugation experiments to assess the co-transferability of ESBL-encoding genes and MDR phenotypes.RESULTS:Twenty-six of 150 fish and meat samples (17%) were positive for ESBL-Salm, including 10/60 fish (17%), 15/60 pork (25%) and 1/30 chicken (3%). Carbapenemase-producing Salmonella strains were not detected. Pork-origin ESBL-Salm were primarily serotypes Rissen (10/15) or a monophasic variant of Typhimurium 4,5,12:i:- (3/15), whereas Saintpaul (3/10) and Newport (4/10) were more common among fish. Most ESBL enzymes were encoded by blaCTX-M-55 genes (24/26) harboured on conjugative IncA/C2 (n = 14) or IncHI2 (n = 10) plasmids. Resistance to up to six additional drug classes was co-transferred by each plasmid type. ESBL-Salm were resistant to almost every antibiotic recommended for severe salmonellosis treatment.CONCLUSIONS:CTX-M-55-type S. enterica are highly prevalent among pork and fish from Phnom Penh markets and their spread appears to be mediated by MDR IncA/C2 and IncHI2 plasmids. Food safety must be improved and veterinary antibiotic use should be regulated to protect public health

Recurrent Hemolytic and Uremic Syndrome Induced by Escherichia Coli.

International audienceA widespread belief is that typical hemolytic and uremic syndrome (HUS) does not recur. We report the case of a patient infected twice with raw milk taken from his own cow and containing a Shiga toxin-producing Escherichia coli O174:H21 that induced recurrent HUS causing severe renal and cerebral disorders. A genomic comparison of the human and bovine Shiga toxin-producing Escherichia coli O174:H21 isolates revealed that they were identical. Typical HUS may recur. Since milk from this animal was occasionally distributed locally, thereby posing a serious threat for the whole village, this particular cow was destroyed