Hemolytic Uremic Syndrome In Germany Research Articles

Estimating true incidence of O157 and non-O157 Shiga toxin-producing Escherichia coli illness in Germany based on notification data of haemolytic uraemic syndrome.

Shiga toxin-producing Escherichia coli (STEC) is an important cause of gastroenteritis (GE) and haemolytic uraemic syndrome (HUS). Incidence of STEC illness is largely underestimated in notification data, particularly of serogroups other than O157 ('non-O157'). Using HUS national notification data (2008-2012, excluding 2011), we modelled true annual incidence of STEC illness in Germany separately for O157 and non-O157 STEC, taking into account the groups' different probabilities of causing bloody diarrhoea and HUS, and the resulting difference in their under-ascertainment. Uncertainty of input parameters was evaluated by stochastic Monte Carlo simulations. Median annual incidence (per 100 000 population) of STEC-associated HUS and STEC-GE was estimated at 0·11 [95% credible interval (CrI) 0·08-0·20], and 35 (95% CrI 12-145), respectively. German notification data underestimated STEC-associated HUS and STEC-GE incidences by factors of 1·8 and 32·3, respectively. Non-O157 STEC accounted for 81% of all STEC-GE, 51% of all bloody STEC-GE and 32% of all STEC-associated HUS cases. Non-O157 serogroups dominate incidence of STEC-GE and contribute significantly to STEC-associated HUS in Germany. This might apply to many other countries considering European surveillance data on HUS. Non-O157 STEC should be considered in parallel with STEC O157 when searching aetiology in patients with GE or HUS, and accounted for in modern surveillance systems.

DİYARE ÖYKÜSÜ OLAN HEMOLİTİK ÜREMİK SENDROM TANILI HASTALARIN KLİNİK ÖZELLİKLERİ

Objective: Hemolytic uremic syndrome (HUS) is characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. The most common form of HUS in children is Shigatoxin-producing Escherichia coli (STEC) related HUS. HUS is the most common causeof acute renal failure in Europe whereas it was not observed in the same frequency in our country. However, in 2011, after the outbreak of Escherichia coli (E. Coli) gastroenteritis and HUS in Germany, we observed significantly increased cases of HUS in our country. In this retrospective study, we aimed to determine the clinical features and prognosis of HUS patients who admitted with a history of diarrhea during this breakout. MaterialsandMethods: We followed up 9 patients with diarrhea associated HUS in 2011. Blood cell count, peripheral blood smear, serum urea, creatinine, electrolytes, complement C3, direct Coombs test, cultures of urine as well as blood and stool, chest X-ray were performed. Results: The mean age was 5.8 ± 4.2 years (3 months-12 years). Six of the patients had complete anuria, the first urine appeared 2-7 days after the presentation. Mean duration of hospitalization was 17.66±13.77 days . In healing process, first platelet count increased. Urine out put appeared soon after the platelet count rose in the anuric patients, mean duration of anuria and oliguria were 7±3 days and 4±5 days , respectively. Conclusion: The results of our study indicate that it may be appropriate to accept as atypical HUS and treat the patients with low C3 levels, vital organ involvement, long-term renal failure and negative stool tests for verotoxin though it cannot be confirmed at the time of admission

Molecular typing of VTEC strains isolated from food, feed and animals

Molecular typing of VTEC strains isolated from food, feed and animals

Overview and Historical Perspectives.

In this overview, we describe the history of Shiga toxin (Stx)-producing Escherichia coli (STEC) in two phases. In phase one, between 1977 and 2011, we learned that E. coli could produce Shiga toxin and cause both hemorrhagic colitis and the hemolytic-uremic syndrome in humans and that the prototype STEC-E. coli O157:H7-adheres to and effaces intestinal epithelial cells by a mechanism similar to that of enteropathogenic E. coli. We also recognized that the genes for Stx are typically encoded on a lysogenic phage; that STEC O157:H7 harbors a large pathogenicity island that encodes the elements needed for the characteristic attaching and effacing lesion; and that the most severe cases of human disease are linked to production of Stx type 2a, not Stx type 1a. Phase two began with a large food-borne outbreak of hemorrhagic colitis and hemolytic-uremic syndrome in Germany in 2011. That outbreak was caused by a novel strain consisting of enteroaggregative E. coli O104:H4 transduced by a Stx2a-converting phage. From this outbreak we learned that any E. coli strain that can adhere tightly to the human bowel (either by a biofilm-like mechanism as in E. coli O104:H4 or by an attaching and effacing mechanism as in E. coli O157:H7) can cause severe diarrheal and systemic illness when it acquires the capacity to produce Stx2a. This overview provides the basis for the review of current information regarding these fascinating and complex pathogens.

Crystallization and sulfur SAD phasing of AggA, the major subunit of aggregative adherence fimbriae type I from theEscherichia colistrain that caused an outbreak of haemolytic-uraemic syndrome in Germany

The outbreak of Shiga toxin-producing Escherichia coli O104:H4 infection in Germany in 2011 was associated with significant mortality and morbidity owing to the progressive development of haemolytic-uraemic syndrome. The outbreak strain emerged recently as a result of horizontal transfer events leading to the acquisition of a number of virulence factors. Among them, aggregative adherence fimbriae type I (AAF/I) are considered to be particularly important since they are involved in the initial attachment of bacteria to the intestinal mucosa. Here, the crystallization and preliminary X-ray diffraction analysis of the major subunit of AAF/I, AggA, are reported. Crystallization of recombinant donor-strand complemented AggA was performed by the vapour-diffusion method. The crystals diffracted to 1.55 Å resolution and belonged to the orthorhombic space group C222(1), with unit-cell parameters a = 77.83, b = 80.17, c = 91.42 Å. Despite a low sulfur content of the protein [0.57%(w/w)], sufficiently accurate initial phases were derived from a sulfur SAD experiment.

Applicability of DiversiLab Repetitive Sequence-Based PCR Method in Epidemiological Typing of EnterohemorrhagicEscherichia coli(EHEC)

Enterohemorrhagic Escherichia coli (EHEC) causes diarrhea, often with severe complications. Rapid and discriminatory typing of EHEC using advanced molecular methods is needed for determination of the genetic relatedness of clones responsible for foodborne outbreaks and for finding out the transmission sources of the outbreaks. This study evaluated the potential of DiversiLab, a semiautomated repetitive sequence-based polymerase chain reaction method for the genotyping of EHEC strains. A set of 52 EHEC strains belonging to 15 O:H serotypes was clustered into 10 DiversiLab groups. All of the O157 strains and one O55 strain were classified into the same group based on a 90% similarity threshold. The other serotypes were classified to their own DiversiLab group, with the exception of one R:H(-) strain that was grouped with O5:H(-) strains. In addition, O26 and O111 strains were grouped together but ultimately subdivided according to their O-serotypes based on a 95% similarity threshold. The O104 strain, which was associated with a major outbreak of hemolytic uremic syndrome in Germany in May 2011, was also classified independently. The DiversiLab performed well in identifying isolates, but the discriminatory power of the repetitive sequence-based polymerase chain reaction method was lower than that of pulsed-field gel electrophoresis. Analysis of 15 enteropathogenic E. coli (EPEC) strains revealed that some EPEC strains clustered together with EHEC strains. Therefore, the DiversiLab system cannot be used to discriminate between these pathogroups. In conclusion, DiversiLab is a rapid and easy system for the primary exclusion of unrelated EHEC strains based on their serotypes, but more discriminatory methods, such as pulsed-field gel electrophoresis, are needed for accurate typing of the EHEC strains.

Distinct Renal Pathology and a Chemotactic Phenotype after Enterohemorrhagic Escherichia coli Shiga Toxins in Non-Human Primate Models of Hemolytic Uremic Syndrome

Enterohemorrhagic Escherichia coli cause approximately 1.5 million infections globally with 176,000 cases occurring in the United States annually from ingesting contaminated food, most frequently E. coli O157:H7 in ground beef or fresh produce. In severe cases, the painful prodromal hemorrhagic colitis is complicated by potentially lethal hemolytic uremic syndrome (HUS), particularly in children. Bacterial Shiga-like toxins (Stx1, Stx2) are primarily responsible for HUS and the kidney and neurologic damage that ensue. Small animal models are hampered by the inability to reproduce HUS with thrombotic microangiopathy, hemolytic anemia, and acute kidney injury. Earlier, we showed that nonhuman primates (Papio) recapitulated clinical HUS after Stx challenge and that novel therapeutic intervention rescued the animals. Here, we present detailed light and electron microscopic pathology examination of the kidneys from these Stx studies. Stx1 challenge resulted in more severe glomerular endothelial injury, whereas the glomerular injury after Stx2 also included prominent mesangiolysis and an eosinophilic inflammatory infiltration. Both toxins induced glomerular platelet-rich thrombi, interstitial hemorrhage, and tubular injury. Analysis of kidney and other organs for inflammation biomarkers showed a striking chemotactic profile, with extremely high mRNA levels for IL-8, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1α and elevated urine chemokines at 48hours after challenge. These observations give unique insight into the pathologic consequences of each toxin in a near human setting and present potential pathways for therapeutic intervention.

Spread of a Distinct Stx2-Encoding Phage Prototype among Escherichia coli O104:H4 Strains from Outbreaks in Germany, Norway, and Georgia

Shiga toxin 2 (Stx2)-producing Escherichia coli (STEC) O104:H4 caused one of the world's largest outbreaks of hemorrhagic colitis and hemolytic uremic syndrome in Germany in 2011. These strains have evolved from enteroaggregative E. coli (EAEC) by the acquisition of the Stx2 genes and have been designated enteroaggregative hemorrhagic E. coli. Nucleotide sequencing has shown that the Stx2 gene is carried by prophages integrated into the chromosome of STEC O104:H4. We studied the properties of Stx2-encoding bacteriophages which are responsible for the emergence of this new type of E. coli pathogen. For this, we analyzed Stx bacteriophages from STEC O104:H4 strains from Germany (in 2001 and 2011), Norway (2006), and the Republic of Georgia (2009). Viable Stx2-encoding bacteriophages could be isolated from all STEC strains except for the Norwegian strain. The Stx2 phages formed lysogens on E. coli K-12 by integration into the wrbA locus, resulting in Stx2 production. The nucleotide sequence of the Stx2 phage P13374 of a German STEC O104:H4 outbreak was determined. From the bioinformatic analyses of the prophage sequence of 60,894 bp, 79 open reading frames were inferred. Interestingly, the Stx2 phages from the German 2001 and 2011 outbreak strains were found to be identical and closely related to the Stx2 phages from the Georgian 2009 isolates. Major proteins of the virion particles were analyzed by mass spectrometry. Stx2 production in STEC O104:H4 strains was inducible by mitomycin C and was compared to Stx2 production of E. coli K-12 lysogens.

An Outbreak of Shiga Toxin-Producing Escherichia coli O104:H4 Hemolytic Uremic Syndrome in Germany: Presentation and Short-term Outcome in Children

In May and June 2011 the largest known outbreak of hemolytic uremic syndrome (HUS) occurred in northern Germany. Because, quite unusually, a large number of adults was affected and the causative Escherichia coli strain, serotype O104:H4, showed an atypical virulence factor pattern, it was speculated that this outbreak was associated with an aggressive course and an unfavorable prognosis also in children. Retrospective analysis of medical records of 90 children and comparison to previous outbreak and sporadic case series. Median age was unusually high (11.5 years) compared with that in historical series. Only 1 patient (1.1%) died in the acute phase. Most patients (67/90 [74%]) received supportive care only. Renal replacement therapy was required in 64 of 90 (71%) of the children. Neurological complications, mainly seizures and altered mental stage, were present in 23 of 90 (26%) patients. Ten patients received plasmapheresis, 6 eculizumab, and 7 a combination of both. After a median follow-up of 4 months, renal function normalized in 85 of 90 (94%) patients, whereas 3 patients had chronic kidney disease stage 3 or 4, and 1 patient (1.1%) still requires dialysis. Complete neurological recovery occurred in 18 of 23 patients. Mild to moderate and major residual neurological changes were present in 3 patients and 1 patient, respectively, although all patients were still improving. E. coli O104:H4 caused the largest HUS outbreak in children reported in detail to date and most patients received supportive treatment only. Initial morbidity, as well as short-term outcome, due to this pathogen, is comparable to previous pediatric series of Shiga toxin-producing E. coli HUS.

Management of hemolytic uremic syndrome

2011 has been a special year for hemolytic uremic syndrome (HUS): on the one hand, the dramatic epidemic of Shiga toxin producing E. coli -associated HUS in Germany brought the disease to the attention of the general population, on the other hand it has been the year when eculizumab, the first complement blocker available for clinical practice, was demonstrated as the potential new standard of care for atypical HUS. Here we review the therapeutic options presently available for the various forms of hemolytic uremic syndrome and show how recent knowledge has changed the therapeutic approach and prognosis of atypical HUS.

Non-O157 Shiga-toxin-producing Escherichia coli

The recent outbreak of a non-O157 Shiga-toxin-producing Escherichia coli (STEC) did not surprise me.1Bielaszewska M Mellmann A Zhang W et al.Characterisation of the Escherichia coli strain associated with an outbreak of haemolytic uraemic syndrome in Germany, 2011: a microbiological study.Lancet Infect Dis. 2011; 11: 671-676Summary Full Text Full Text PDF PubMed Scopus (589) Google Scholar In 2007,2Bettelheim KA The non-O157 shiga-toxigenic (verocytotoxigenic) Escherichia coli; under-rated pathogens.Crit Rev in Microbiol. 2007; 33: 67-87Crossref PubMed Scopus (227) Google Scholar I noted the widespread nature of non-O157 STEC: most ruminants carry them in their intestinal flora, and improved methods of isolation suggest that the serotype could be present in almost all ruminants; whereas O157 STEC are the minority, if found at all. O157 isolates are rare when all STEC are sought rather than a single serotype (by use of a O157-specific medium). The absurdity of the use of special media that detect the O157 clone only was shown in 1996 during an investigation of an outbreak of mainly STEC O111, but also other serotypes, such as O157.3Goldwater PN Bettelheim KA An outbreak of hemolytic uremic syndrome due to Escherichia coli O157:H7: or was it?.Emerg Infect Dis. 1996; 2: 153-154Crossref PubMed Scopus (34) Google Scholar The degree of clinical severity of the patients' condition was proportional to the number of different STEC serotypes to which they were exposed, rather than a particular STEC serotype. Many laboratories do not seem to take into account the diversity of E coli serotypes in the gastrointestinal tract of a human being at any one time.4Bettelheim KA Faiers M Shooter RA Serotypes of Escherichia coli in normal stools.Lancet. 1972; 300: 1224-1226Summary Scopus (22) Google Scholar A similar situation exists with regard to laboratory investigations in animals. The full investigation of outbreaks is essential to understand their causes. In the Comment5Pennington H Escherichia coli O104, Germany 2011.Lancet Infect Dis. 2011; 11: 652-653Summary Full Text Full Text PDF PubMed Scopus (13) Google Scholar about the German O104 outbreak, Hugh Pennington notes that four of nine outbreaks of intestinal infections linked to bean sprouts were caused by E coli O157. These bean sprouts could have been contaminated with animal faecal matter, and other STEC serotypes might have been involved. The development of a medium that will select for all STEC rather than specifically for one or a few could help our understanding of human infection and is needed urgently. An organisation such as the European Centre for Disease Prevention and Control should initiate such an endeavour. I declare that I have no conflicts of interest.

Escherichia coli O104:H4 south-west France, June 2011

Comment on: Characterisation of the Escherichia coli strain associated with an outbreak of haemolytic uraemic syndrome in Germany, 2011: a microbiological study. [Lancet Infect Dis. 2011]

Rapid identification and validation of specific molecular targets for detection of Escherichia coli O104:H4 outbreak strain by use of high-throughput sequencing data from nine genomes.

In May 2011, an enteroaggregative verocytotoxin-producing strain of Escherichia coli O104:H4 caused an outbreak of hemolytic uremic syndrome in Germany. Although traditional culture and phenotypic tests can identify the outbreak strain, rapid molecular testing is useful for timely diagnosis. While

Characterisation of the Escherichia coli strain associated with an outbreak of haemolytic uraemic syndrome in Germany, 2011: a microbiological study

In an ongoing outbreak of haemolytic uraemic syndrome and bloody diarrhoea caused by a virulent Escherichia coli strain O104:H4 in Germany (with some cases elsewhere in Europe and North America), 810 cases of the syndrome and 39 deaths have occurred since the beginning of May, 2011. We analysed virulence profiles and relevant phenotypes of outbreak isolates recovered in our laboratory. We analysed stool samples from 80 patients that had been submitted to the National Consulting Laboratory for Haemolytic Uraemic Syndrome in Münster, Germany, between May 23 and June 2, 2011. Isolates were screened with standard PCR for virulence genes of Shiga-toxin-producing E coli and a newly developed multiplex PCR for characteristic features of the outbreak strain (rfb(O104), fliC(H4), stx(2), and terD). Virulence profiles of the isolates were determined with PCR targeting typical virulence genes of Shiga-toxin-producing E coli and of other intestinal pathogenic E coli. We sequenced stx with Sanger sequencing and measured Shiga-toxin production, adherence to epithelial cells, and determined phylogeny and antimicrobial susceptibility. All isolates were of the HUSEC041 clone (sequence type 678). All shared virulence profiles combining typical Shiga-toxin-producing E coli (stx(2), iha, lpf(O26), lpf(O113)) and enteroaggregative E coli (aggA, aggR, set1, pic, aap) loci and expressed phenotypes that define Shiga-toxin-producing E coli and enteroaggregative E coli, including production of Shiga toxing 2 and aggregative adherence to epithelial cells. Isolates additionally displayed an extended-spectrum β-lactamase phenotype absent in HUSEC041. Augmented adherence of the strain to intestinal epithelium might facilitate systemic absorption of Shiga toxin and could explain the high progression to haemolytic uraemic syndrome. This outbreak demonstrates that blended virulence profiles in enteric pathogens, introduced into susceptible populations, can have extreme consequences for infected people. German Federal Ministry of Education and Research, Network Zoonoses.

Characteristics of the enteroaggregative Shiga toxin/verotoxin-producing Escherichia coli O104:H4 strain causing the outbreak of haemolytic uraemic syndrome in Germany, May to June 2011

The Escherichia coli strain causing a large outbreak of haemolytic uraemic syndrome and bloody diarrhoea in Germany in May and June 2011 possesses an unusual combination of pathogenic features typical of enteroaggregative E. coli together with the capacity to produce Shiga toxin. Through rapid national and international exchange of information and strains the known occurrence in humans was quickly assessed.We describe simple diagnostic screening tools to detect the outbreak strain in clinical specimens and a novel real-time PCR for its detection in foods.

Novel type of fimbriae encoded by the large plasmid of sorbitol-fermenting enterohemorrhagic Escherichia coli O157:H(-).

Sorbitol-fermenting (SF) enterohemorrhagic Escherichia coli (EHEC) O157:H(-) have emerged as important causes of diarrheal diseases and the hemolytic-uremic syndrome in Germany. In this study, we characterized a 32-kb fragment of the plasmid of SF EHEC O157:H(-), pSFO157, which differs markedly from plasmid pO157 of classical non-sorbitol-fermenting EHEC O157:H7. We found a cluster of six genes, termed sfpA, sfpH, sfpC, sfpD, sfpJ, and sfpG, which mediate mannose-resistant hemagglutination and the expression of fimbriae. sfp genes are similar to the pap genes, encoding P-fimbriae of uropathogenic E. coli, but the sfp cluster lacks homologues of genes encoding subunits of a tip fibrillum as well as regulatory genes. The major pilin, SfpA, despite its similarity to PapA, does not cluster together with known PapA alleles in a phylogenetic tree but is structurally related to the PmpA pilin of Proteus mirabilis. The putative adhesin gene sfpG, responsible for the hemagglutination phenotype, shows significant homology neither to papG nor to other known sequences. Sfp fimbriae are 3 to 5 nm in diameter, in contrast to P-fimbriae, which are 7 nm in diameter. PCR analyses showed that the sfp gene cluster is a characteristic of SF EHEC O157:H(-) strains and is not present in other EHEC isolates, diarrheagenic E. coli, or other Enterobacteriaceae. The sfp gene cluster is flanked by two blocks of insertion sequences and an origin of plasmid replication, indicating that horizontal gene transfer may have contributed to the presence of Sfp fimbriae in SF EHEC O157:H(-).

Genotypic and phenotypic changes in the emergence of Escherichia coli O157:H7.

Escherichia coli O157:H7 is a foodborne pathogen distinguished from typical E. coli by the production of Shiga toxins (Stx) and the inability to ferment sorbitol (SOR) and to express beta-glucuronidase (GUD) activity. An allele-specific probe for the GUD gene (uidA) and multilocus enzyme electrophoresis were used to elucidate stages in the evolutionary emergence of E. coli O157: H7. A point mutation at +92 in uidA was found only in O157:H7 and its nonmotile relatives, including a SOR+ O157:H clone implicated in outbreaks of hemolytic-uremic syndrome in Germany. The results support a model in which O157:H7 evolved sequentially from an O55:H7 ancestor, first by acquiring the Stx2 gene and then by diverging into two branches; one became GUD- SOR- , resulting in the O157:H7 clone that spread worldwide, and the other lost motility, leading to the O157:H clone that is an increasing public health problem in Europe.