[Animal sources of Clostridium difficile]. / K problematice animálních zdroju Clostridium difficile.

The bacterium Clostridium difficile is pathogenic for both humans and animals. This feared nosocomial infectious agent is increasingly more important in the community as well. Like in humans, the gastrointestinal tract is infected in animals. The bacterium may be transmitted from animals to humans via the food chain (e.g. pork meat) or by direct contact. Identical human and animal isolates of C. difficile have been reported in several studies. The article presents results from a small local study aimed at detecting C. difficile and its toxins in the District of Olomouc, Czech Republic, by 3 different methods.

[Virulence factors in vancomycin-susceptible and vancomycin-resistant enterococci in the University Hospital Olomouc]. / Faktory virulence u vankomycin citlivých a vankomycin rezistentních enterokoku ve falkultní nemocnici olomouc.

BACKGROUND: Bacteria of the genus Enterococcus are a normal part of the intestinal microflora but also important nosocomial pathogens. An alarming fact is increasing resistance to antimicrobial agents such as vancomycin (VRE). Enterococci frequently produce numerous virulence factors, e.g. gelatinase, surface protein, adhesins and sex pheromones. Their genes, with respect to vancomycin resistance, are studied. MATERIAL AND METHODS: In 108 isolates obtained from various clinical samples (except for stools) taken from patients in the University Hospital Olomouc and divided into VRE (n = 54) and control, vancomycin-susceptible (n = 54) groups, the prevalence of genes for gelatinase (gelE), surface protein (esp) and sex pheromones (cpd, cob and ccf) was investigated. For genetic detection, real-time PCR was used. RESULTS: In the control group of vancomycin-susceptible enterococci, only six isolates (11.1 %) showed none of the studied virulence factors. The most prevalent gene was ccf (77.7 %, n = 42), followed by cpd in 66.6 % (36), gelE in 55.5 % (30), esp in 46.3 % (25) and cob in 38.9 % (21). In the VRE group, 17 isolates (31.5%) contained none of the studied genes. More prevalent was esp in 62.9 % (34), substantially less frequent were cpd in 5.6 % (3), cob in 5.6 % (3), ccf in 5.6 % (3) and gelE in 3.7 % (2). CONCLUSIONS: In VRE a smaller occurence, i.e. four out of the five studied virulence factors, were detected. The lower prevalence of genes for virulence factors was probably due to their species representation (substantially higher frequency of Enterococcus faecium in which these genes are mostly much less prevalent).

Prevalence of genes encoding extracellular virulence factors among meticillin-resistant Staphylococcus aureus isolates from the University Hospital, Olomouc, Czech Republic.

A rather fast and complicated progression of an infection caused by some strains of Staphylococcus aureus could be associated with the expression and co-action of virulence factor complexes in these strains. This study screened the antibiotic susceptibility and prevalence of virulence markers in isolates of meticillin-resistant S. aureus (MRSA) obtained from patients hospitalized at the University Hospital in Olomouc, Czech Republic. A total of 100 isolates was screened for 13 genes encoding extracellular virulence determinants (tst, pvl, eta, etb, sea, seb, sec, sed, see, seg, seh, sei and sej) and for their distribution in sample types. Eighty-nine isolates were positive for at least one of the genes. Genes for etb, pvl, see and seh were not detected in any of the MRSA isolates. No statistically significant differences in the occurrence of the determinants studied among sample types were found.

Genotypic characterisation of vancomycin-resistant Enterococcus faecium isolates from haemato-oncological patients at Olomouc University Hospital, Czech Republic.

This study describes the first molecular characterisation of clinical isolates of vancomycin-resistant enterococci (VRE) in the Czech Republic. Of 2647 patient isolates of Enterococcus spp. from 1997-2002, 121 (4.6%) were identified as VRE. The most common isolates were VanA+ Enterococcus faecium (78%) and VanB+ Enterococcus faecalis (10%). In addition, five VanA+ E. faecium isolates were obtained from environmental and staff sampling. Macrorestriction analysis of SmaI restriction fragment length polymorphism was performed for 54 VanA+ E. faecium clinical isolates and the five VanA+ E. faecium environmental isolates. Thirty-two unique restriction endonuclease patterns were identified, including two predominant clonal types represented by five or more isolates. Two environmental VanA+ E. faecium isolates were closely related to two patient isolates, which had an identical SmaI macrorestriction pattern. The results indicated potential survival of strains in the hospital environment and possible subsequent transmission to hospitalised patients.

The influence of antibiotic use on the occurrence of vancomycin-resistant enterococci.

BACKGROUND: Several studies have documented the influence of antibiotic selective pressure, mainly from the use of glycopeptides, third-generation cephalosporins, quinolones and lincosamides, on the frequency of vancomycin-resistant enterococci (VRE) occurrence in hospitals. The aim of this study was to evaluate the relationship between VRE occurrence and antibiotic use in the Department of Hemato-Oncology of the Teaching Hospital in Olomouc (DHO), Czech Republic, over a 6-year period under standard and unchanged hygienic and epidemiological conditions. METHODS: During the period of 1998-2003, Enterococcus sp. strains and VRE were isolated by standard methods from clinical samples taken from DHO in-patients. The frequency of VRE occurrence was expressed as the number of isolated strains per 100 bed-days/year. DHO antibiotic consumption data were processed according to the anatomical therapeutic chemical (ATC)/defined daily dose (DDD) system valid in 2003 and expressed in defined daily dose per 100 bed-days (DDD/100 bed-days) for each year of the period. RESULTS: Since 1998, the occurrence of VRE decreased significantly (from 0.28 to 0.17 VRE/100 bed-days in 2001). Between 2001 and 2003, a significant (P < 0.05) increase from 0.17 to 0.38 was observed. The antibiotic use decreased from 205.2 in 1998 to 161.0 DDD/100 bed-days in 1999 and after an increase in 2001 (to 181.8 DDD/100 bed-days) it remained relatively stable. A significant decrease was observed in third-generation cephalosporins and quinolones (from 29.5 to 9.7 and from 42.2 to 30.2 DDD/100 bed-days respectively) between 1998 and 1999. In 2002-2003, the use of third-generation cephalosporins and glycopeptides increased substantially (from 10.1 to 13.9 and from 11.3 to 15.2 DDD/100 bed-days respectively). The Pearson correlation value was significantly positive (P < 0.05) for VRE occurrence and the use of glycopeptides and third-generation cephalosporins. CONCLUSIONS: While our study confirms the effect of use of glycopeptides and third-generation cephalosporins on occurrence of VRE, no influence of quinolones and lincosamides over the 6-year period was shown.

The occurrence of vancomycin-resistant enterococci in hematological patients in relation to antibiotic use.

Very important bacterial pathogens found in hematological patients at present are vancomycin-resistant enterococci (VRE). The main goal of this retrospective study was to assess their occurrence in relation to antibiotic use. We isolated 1918 Enterococcus strains, in toto, 138 (7.2%) of which proved to be VRE. The VRE most frequently identified were Enterococcus faecium VanA (77%) and Enterococcusfaecalis VanB (12%), mostly isolated from stools (57%). Comparing the development of the selection pressure of antibiotics and percentage of VRE in each period of observation, an effect of the administration of each antibiotic group on the occurrence of VRE can be presumed. A reduction in the administration of third generation cephalosporins, glycopeptides and fluoroquinolones and its replacement by penicillin antibiotics combined with inhibitors of bacterial beta-lactamases, contributed to the cessation of VRE incidence and succeeding reduced occurrence from 15.1% in the second half of 1998 to 6.1% in the first half of 2000.

Occurrence of vancomycin-resistant enterococci in relation to the administration of glycopeptide antibiotics.

Occurrence of vancomycin-resistant enterococci and its relationship to the administration of glycopeptide antibiotics (vancomycin, teicoplanin) was described. A total number of 628 strains of the genus Enterococcus was isolated in the Hemato-oncologic Department of the University Hospital in Olomouc in 1997. Seven strains (1.1%) were found to be resistant to vancomycin. Five of them were identified as Enterococcus faecalis of phenotype VanB, and two strains as E. faecium of phenotype VanA. The administration of vancomycin and teicoplanin in the Hemato-oncologic Department amounted to 85.7% and 89.2%, respectively, of the total consumption of these drugs at the University Hospital.