DNA polymorphisms among Escherichia coli isolated from bacteriuric women

Restriction fragment length polymorphism (RFLP) patterns, plasmid profiles, and antimicrobial susceptibility patterns of paired sequential Escherichia coli isolates from antibiotic-treated and untreated elderly women were analyzed. Isolates from 26 of 27 subjects who were treated successfully with antibiotics but became reinfected differed by RFLP analysis, whereas 10 of 12 subjects who failed treatment and 11 of 14 untreated subjects had paired isolates with identical RFLP banding patterns. Only 40 of the 53 pairs of isolates could be analyzed by plasmid profiles; 36 of these 40 were concordant with RFLP analysis. Antimicrobial susceptibility patterns showed poor concordance with RFLP analysis. This study demonstrates the utility of RFLP analysis and indicates that isolation of E. coli from elderly women after sterilization of the urinary tract usually results from introduction of a new strain; elderly women who fail antibiotic therapy or receive no therapy may remain persistently infected with the same E. coli strain.     

Hemagglutinating activity of Escherichia coli isolated from the respiratory tract in comparison with those isolated from urine feces and blood

Various bacteria with pili are able to agglutinate human and animal red blood cells. Hemagglutinating activity of 131 strains of Escherichia coli isolated from respiratory tract (24 strains), urine (64 strains), feces (36 strains) and blood (7 strains) were tested using human type A, guinea pig, bovine and chicken erythrocytes. Concerning the hemagglutination activity for erythrocytes from at least one of four species (human, guinea pig, bovine, chicken), the strains isolated from respiratory tract showed a higher level than those isolated from feces (p less than 0.01) or those isolated from blood (p less than 0.1). Agglutination of human erythrocytes: Of 131 strains, mannose-sensitive agglutination was observed in 31 strains, mannose-resistant agglutination in 40 strains and non-agglutination in 60 strains. More agglutinated strains were isolated from the respiratory tract than those isolated from blood but not with statistical significance (p less than 0.1). Agglutination of guinea pig erythrocytes: Of 131 strains, mannose-sensitive agglutination was observed in 56 strains, mannose-resistant agglutination in 10 strains and non-agglutination in 65 strains. More agglutinated strains were isolated from the respiratory tract than from urine, feces and blood (p less than 0.01), and of those, 89% were mannose-sensitive agglutination. Agglutination of bovine erythrocytes: Of the 131 strains, mannose-sensitive agglutination was observed in 4 strains, mannose-resistant agglutination in 6 strains and non-agglutination in 121 strains. Therefore, only a few agglutinated strains were seen.(ABSTRACT TRUNCATED AT 250 WORDS)     

Molecular investigation of pathogenic factors of suspected-diarrheogenic Escherichia coli isolates from patients feces

One hundred fifty-one O serotypable Escherichia coli strains which were assumed diarrheogenic E. coli among 2,240 strains of E. coli isolated from the in- and outpatients stools with or without gastrointestinal symptoms at Kyorin University Hospital from February 1994 to September 1996 were examined for the relationship between the possession of eight pathogenic factor-related genes and gastrointestinal symptoms of the patients using the polymerase chain reaction (PCR) for these strains. The rate of possession of pathogenic factor-related genes in the E. coli examined was 20.5% (31 strains) and gastrointestinal symptoms were found in all the patients with these strains except one. In the patients without gastrointestinal symptoms, E. coli isolates that possesses these genes was detected in only one case during 61 cases. The respective genes detected were eaeA and astA in each 14 strains, VT1 in 6, VT2 in 5, ST1b in 4, aggR in 3 and LT in 2, ST1a and invE gene was not detected. In particular, the O157 strains were found in 55.6% (5/9 strains) for these genes, and individual strains had VT1, VT2, eaeA and astA genes simultaneously. In contrast, none of these related genes was found in 9 strains of enteroinvasive serotype but enteropathogenic E. coli-related genes were found in 3 strains. The rate of possession of the genes related to enterotoxigenic E. coli, O159 which was most frequently isolated was low as 2.3% (1/43 strains, astA gene) and there were strains showing low correlation to the state of possession of the genes with the O serotype. Since the prevalence of the gastrointestinal symptoms is clearly high for the case which possesses the strain of which the pathogenic factor-related gene was detected, it was suggested that detection of pathogenic factor-related genes in E. coli isolates from feces using the PCR could be an effective means to decide whether the bacteria concerned was a causal bacteria or not in clinical practice.     

Listeria isolations from feces of patients with diarrhea and from healthy food handlers

Summary A study was undertaken on the presence and frequency ofListeria sp. in feces from 1,000 patients suffering from diarrheal diseases and from 2,000 healthy persons. Furthermore, the feces of patients were examined for other well-documented enteropathogens such asCampylobacter, Salmonella, Shigella, Staphylococcus aureus, Yersinia enterocolitica, protozoa and rotavirus as well as for organisms of questionable enteropathogenic potency such as fungi, i.e. Candida. Finally, in continuation of previously described investigations of the enteropathogenic role ofProteus mirabilis but not ofProteus vulgaris, both these species were studied too. OnlyListeria innocua andListeria monocytogenes could be detected in the investigated fecal specimens. There were no differences of the frequencies ofL. innocua, andL. monocytogenes between patients and healthy persons. 17 strains (= 1.7%) ofL. innocua and six strains (= 0.6%) ofL. monocytogenes were isolated from 1,000 samples of patients. As a comparison 2,000 fecal samples from healthy people contained 40 strains (= 2.0%) ofL. innocua and 16 strains (= 0.8%) ofL. monocytogenes. A coincidence study showed that there were no statistically significant correlations between well-known enteropathogens andListeria sp.,Proteus sp. or any of the other isolates. Significant correlations were found only between harmless species such asL. innocua andP. vulgaris.

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Listerien im Stuhl von Diarrhöe-Patienten und von gesunden Personen aus dem Lebensmittelgewerbe

Zusammenfassung In der vorliegenden Studie wurde das Vorkommen und die Häufigkeit von Listerien in Stuhlproben von 1000 Patienten mit Diarrhöe und 2000 Gesunden untersucht, um das Spektrum der verschiedenenListeria-Arten kennenzulernen. Zusätzlich wurden die Fäzes der Kranken auf bekannte darmpathogene Erreger wieCampylobacter, Salmonella, Shigella, Staphylococcus aureus, Yersinia enterocolitica, Protozoen und Rotaviren untersucht sowie auf Keime fraglich enteropathogener Bedeutung wie etwa Hefepilze. In Fortführung vorausgegangener Arbeiten wurden sowohl der enteropathogeneProteus mirabilis als auch der im Intestinaltrakt offensichtlich apathogeneProteus vulgaris in die Studie miteinbezogen. In den Fäzesproben konnten lediglich die beiden Listeria-ArtenListeria innocua undListeria monocytogenes gefunden werden. Offensichtlich sind alle übrigenListeria-Arten im menschlichen Darmtrakt wesentlich seltener. Die beiden vorhandenen kamen bei Gesunden und Kranken gleich häufig vor. Im Kollektiv der Gesunden konnten 40L. innocua-Stämme (= 2,0%) und 16L. monocytogenes-Stämme (= 0,8%) isoliert werden, bei dem Kollektiv der Diarrhöe-Erkrankten waren es 17L. innocua-Stämme (= 1,7%) und sechsL. monocytogenes-Stämme (= 0,6%). Daraus geht deutlich hervor, daß Listerien an der diarrhöischen Symptomatik unbeteiligt sind. Eine Koinzidenzstudie zur Frage möglicher Zusammenhänge zwischen verschiedenen enteropathogenen Erregern ergab keine statistisch signifikaten Korrelationen. Lediglich zwischen den beiden harmlosen ArtenL. innocua undProteus vulgaris wurde eine Korrelation gefunden.

     

Comparison of O-serotype distribution of Escherichia coli isolated from faecal specimens of patients with sporadic diarrhea and healthy persons and regional difference in Japan

To investigate the isolation frequency of O-serotype of Escherichia coli, a total of 1,563 faecal specimens obtained from patients with sporadic diarrhea in Ishikawa between July 1997 and June 1998, were examined. As a result of O-serotyping of isolated strains using commercially E. coli antisera (43 different types), 247 strains of 29 different O-serotypes were isolated. Isolation rate was 15.8%. Most predominant O-serotype was O1 (128 strains, 52%), followed by O18 (26 strains, 11%), O6 (17 strains, 7%), O111 (16 strains, 6%), and these 4 different O-serotypes took up three quarters of the isolated E. coli. Between August 1996 and May 1997, E. coli isolation from faecal samples of 51,893 healthy persons and O-serotyping of isolated strains using commercial antisera to 6 predominant O-serotypes (O-26, 111, 114, 128, 157 and O1) of VTEC/EHEC were carried out. Among 6 O-serotypes, the most predominant O-serotype was O1 (93% of isolates), followed by O26, 111, 128 (6%) and O114, 157 (1%). These isolation frequencies in patients were 80%, 18%, 2%, respectively, have resembled each other in healthy persons in many points. In a similar way, of these distributions of O-serotype of strains hemolysed on Beutin's blood agar plates, we compared patients with healthy persons. Fifty-six strains (3.6% of the total) of E. coli of different O-serotypes were isolated from 1,563 patients and 57 strains (2.8% of the total) belonging to 11 serotypes from 2,036 healthy persons. As a result of O-serotype frequency, both groups resembled each other. O18 and O6, the most predominant O-serotypes, occupied 64% of the isolated strains in patients and 74% in healthy persons. Next in patients, O1, 26 were 7%--level, O28 ac, 152, 157 were 4%--level, respectively, and in healthy persons. O1 was 5%--level, O28 ac, 55, 146, 152 were 4%--level respectively. In the comparison of O-serotype frequency of E. coli isolated from sporadic diarrhea in other 5 areas (Kanto district, Tokyo, Oita, Aichi and Ishikawa), O1, 6, 8, 18, 25, 26, 55, 86a, 111, 125, 126, 127a, 128, 146, 148, 157 and 166 (17 types) have covered a wide area. On the other hand, O29, 44, 78, 112ac, 115, 136, 143, 152, 168 and 169 (10 types) have a tendency to distribute in local areas, we believe that there are regional differences even in the same Japanese territory.     

Occurrence of Escherichia coli virulence genes in feces of wild birds from Central Italy

Objective: To investigate the potential role of wild birds as fecal spreaders of enteropathogenic,enterohemorrhagic and Shiga-toxins producing Escherichia coli(E. coli),enteropathogenic E. coli,enterohemorrhagic E. coli and Shiga toxin-producing E. coli strains. Methods: Fecal samples collected from 121 wild birds of different orders and species were submitted to molecular analyses. In particular,eaeA encoding intimin,hlyA encoding for hemolysin,stx1 and stx2 genes encoding Shiga-toxins 1 and 2,respectively,were investigated. Results: Overall,21(17.35%) fecal samples resulted positive for at least one of the investigated genes. In detail,12(9.91%) samples were positive for eaeA,10(8.26%) for stx1,4(3.31%) for hylA and 1(0.83%) for stx2. An owl(Athene noctua) positive for the four investigated genes suggesting that it harbored a STEC strain. However,virulence genes characterizing EPEC,and EHEC strains were mainly found among seagulls,waterfowl and feral pigeons. Conclusions: Seagulls,waterfowl and feral pigeons,which frequently reach and contaminate rural,urban and peri-urban areas with their droppings,may be important sources of E. coli infection for other animals and humans.     

Escherichia coli bacteremia in patients with malignant diseases.

Of 142 episodes of Escherichia coli bacteremia that were reviewed, appropriate antibiotics were administered during 98 episodes diagnosed premortem and 74 episodes (71%) responded. The highest cure rates were observed when the portals of entry were the urinary tract and soft tissues. Administration of adrenal corticosteroids did not affect the outcome of these patients. The patients' neutrophil counts at the onset and during infection were important factors in predicting survival. Septic shock occurred in 13% of all episodes, and only 11% of these patients responded. Of those patients who died, 63% died within the first 24 hours. Aminoglycosides, cephalosporins, and semisynthetic penicillins used alone or in combination offered optimal coverage.     

Virulence properties of Escherichia coli strains isolated from patients with inflammatory bowel disease.

Escherichia coli strains cultured from 74 patients with inflammatory bowel disease at different stages of disease activity (Crohn's disease (40), ulcerative colitis (34)) and 18 healthy controls were studied in relation to haemolysin and verotoxin production and enteroadherence. Disease activity was assessed by standard clinical and laboratory tests. Haemolytic E coli were isolated from 18% of patients with Crohn's disease, 24% with ulcerative colitis, and 11% of healthy controls. None of these differences was significant. No verotoxin producing strains were detected among the 216 E coli isolates examined but the extract from five strains (Crohn's (4), ulcerative colitis (1) produced a distinctive cytopathic effort on Vero cell monolayers which was later shown not to be due to verotoxin. The adhesion indices of E coli isolates cultured were: mean (SEM) 42.2 (6.4) for Crohn's disease, 43.3 (6.2) for ulcerative colitis, and 11.3 (2.0) for normal controls (p less than or equal to 0.0001). Adhesive E coli were isolated from 62% of patients with Crohn's disease and 68% with ulcerative colitis but from only 6% of normal controls (p less than or equal to 0.0002). Neither haemolysin production nor enteroadherence was dependent upon disease activity, disease location, sulphasalazine treatment, or previous intestinal resection. These results indicate that only enteroadherent E coli were frequently associated with inflammatory bowel disease; their relation to the pathogenesis of these conditions, however, remains uncertain.     

Escherichia coli antibodies in patients with inflammatory bowel disease.

Sera from 30 patients with inflammatory bowel disease (IBD) (16 with Crohn's disease (CD) and 14 with ulcerative colitis (UC) were assayed for the presence of antibodies against 159 Escherichia coli O-antigens and compared with sera from 16 matched control subjects. The majority of patients with IBD had agglutinating antibodies to a higher number of Escherichia coli O-antigens and in higher titres than the control group. The number of positive agglutinins was O-33 mean 13.8 in CD, O-26 mean 7.9 for UC, and O-7 mean 1.5 in controls. Eight patients with IBD and arthropathy had antibodies to fewer O-antigens (O-7 mean 3.2). The antibodies were in the IgG and IgM, in titres corresponding to original values. No specific O-serotypes were associated with IBD. Common serotypes, R-plasmid carrying serotypes, and those associated with shigella-like adult diarrhoea were detected. O14 was detected only in five patients and O119 in none. There was no correlation between the number of Escherichia coli agglutinins and the site and severity of the disease or type of therapy. It is suggested that the presence of the high numbers of Escherichia coli antibodies is secondary to the disease process and is unlikely to be causally involved in the pathogenesis of the disease, but may play a role in the perpetuation of the disease and in the extraintestinal complications.     

健康人群肠道大肠埃希菌耐药性调查研究

目的 研究健康人群肠道大肠埃希菌对抗生素的耐药性。方法 健康人肛拭子标本150份取自深圳市健康人群，按《预防医学微生物学及检验技术》的方法分离大肠埃希菌，K-B法测定细菌对15种抗生素的耐药性。结果 健康人群大肠埃希菌对四环素、萘啶酸、磺胺甲基异恶唑、氨苄西林、复方新诺明等抗生索有耐受性，耐药率分别为63．33％、49．33％、40．67％、38．67％和35．33％；对阿米卡星、氨曲南的耐药率分别为0和0．67％，对头孢类抗生素的耐药率为0～6．67％。其中121株（占80．67％）对1种以上抗生素耐药，87株（占58．00％）对2种以上抗生素耐药，36株（占24．00％）对5种以上抗生素耐药，2株（占1．33％）对9种抗生索耐药。结论 深圳市健康人群肠道大肠埃希菌耐药性较严重，故应严格控制抗生索使用并继续做好耐药性监测工作，及时掌握细菌对抗生素耐药性变化情况。     

Enterotoxigenic Escherichia coli isolated from patients at a hospital in Dacca.

Enterotoxigenic strains of Escherichia coli, a significant cause of acute, watery, cholera-like diarrhea, were isolated from 23 of 65 patients with diarrhea in whom no other enteric pathogens were found during one week (November 1974) at the Cholera Research Hospital, Dacca, Bangladesh. Diarrhea associated with enterotoxigenic strains of E. coli occurred primarily in adults but affected persons of all age groups and could not be distinguished from cholera or from other cholera-like diarrhea on clinical grounds. Routine bacteriologic methods were inadequate for identification of enterotoxigenic E. coli as the etiologic agent of the diarrhea. The enterotoxigenic E. coli, producing heat-stable and/or heat-labile enterotoxin, were detected by use of assays in the Y1 adrenal cell, the Chinese hamster ovary cell, the rabbit ileal loop, and the infant mouse. The two tissue culture assays yielded comparable results in tests with 640 (193 positive, 447 negative) of 643 isolates of E. coli. The results of this study support the idea that enterotoxigenic E. coli play a significant role as pathogens in the etiology of acute watery diarrhea.     

直接从粪便中检测致犊牛腹泻产肠毒素大肠杆菌的双重PCR方法的建立与应用

目的产肠毒素大肠杆菌(Enterototxigenic,Escherichia Coli,ETEC)是造成人和动物腹泻的主要病原之一,也是造成新生乳用犊牛腹泻的主要原因,一株ETEC可能产生一种或者多种肠毒素。根据产肠毒素大肠杆菌产生的两种主要毒素的基因序列,设计了两对引物,建立多重PCR方法。该方法仅用4.5小时即可检测出导致犊牛腹泻的产肠毒素大肠杆菌菌株,具有敏感度高、特异性强和检测速度快等特点。本试验的目的是用所建立的多重PCR方法来确定ETEC在导致犊牛腹泻中的作用。采用该方法对乳用犊牛的203个腹泻样品进行了检测,结果,用传统的分离培养方法得到的203株典型大肠杆菌中有135株为ETEC;其中LT阳性为105株,ST阳性为126株,LT+ST阳性的为96株,阳性率为66.5%。而采用直接从粪样中提取PCR模板的方法进行PCR,检测到146个犊牛粪样为ETEC阳性,其中LT阳性为112株,ST阳性为137株,LT+ST阳性为103株,阳性率为71.9%,明显高于传统的检测方法;并且所检测到的146个ETEC阳性的犊牛粪样完全包含用传统的分离培养方法得到的135个阳性粪样,且基因分型结果相同。     

Enterotoxigenic Escherichia coli isolated from food.

Approximately 8% of 240 isolates of Escherichia coli obtained from food of animal origin in the United States were found to be enterotoxigenic, as determined in adrenal cells, rabbit ileal loops, and assays in infant mice. These organisms were of diverse serotypes that are not included among the so-called enteropathogenic serotypes and would not have been identified by usual laboratory methods. These enterotoxigenic E. coli are of potential importance to public health.     

Adhesive and hydrophobic properties of Escherichia coli from the rectal mucosa of patients with ulcerative colitis.

The adherent properties and hydrophobicity of Escherichia coli isolates have been compared from the rectal mucosa of patients with active and inactive ulcerative colitis and from a control patient group. Patients with active colitis were colonised less frequently and with lower numbers of E coli than were control patients. Mannose resistant adhesion to HEp-2 cells was determined for 124 isolates of E coli and surface hydrophobicity was estimated by salt agglutination in 96 of these isolates. There was no significant difference in the distribution of adherent strains between the colitis patient groups or with disease activity. E coli from the control patients were marginally less adhesive than those from colitics. The hydrophobicity of isolates did not differ significantly between colitic and control groups nor were there significant differences correlated with disease activity. Furthermore, for these mucosal E coli isolates, hydrophobicity and mannose resistant adhesion were unrelated characteristics.     

Genotypic characterization of virulence factors in Escherichia coli strains from patients with cystitis

Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (alpha-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.