The molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in the Czech Republic.

OBJECTIVES: To gain data on the current molecular epidemiology and resistance of MRSA in the Czech Republic. METHODS: Between September 2017 and January 2018, a total of 441 single-patient MRSA isolates were collected from 11 Czech hospitals and analysed by spa typing, SCCmec typing, antibiotic susceptibility testing, detection of the PVL toxin and the arcA gene. RESULTS: Of all MRSA isolates, 81.41% (n = 359) belonged to the CC5-MRSA clone represented by the spa types t003 (n = 136), t586 (n = 92), t014 (n = 81), t002 (n = 20) and other spa types (n = 30); a majority of the CC5 isolates (n = 348, 96.94%) carried SCCmec type II. The occurrence of CC5-MRSA was more likely in older inpatients and associated with a healthcare origin (P < 0.001). The CC5-MRSA isolates were resistant to more antimicrobial drugs compared with the other MRSAs (P < 0.001). Interestingly, t586 was detected in blood samples more often than the other spa types and, contrary to other spa types belonging to CC5-MRSA, t586 was not associated with patients of advanced age. Other frequently found lineages were CC8 (n = 17), CC398 (n = 11) and CC59 (n = 10). The presence of the PVL was detected in 8.62% (n = 38) of the MRSA isolates. CONCLUSIONS: The healthcare-associated CC5-MRSA-II lineage (t003, t586, t014) was found to be predominant in the Czech Republic. t586 is a newly emerging spa type in the Czech Republic, yet reported rarely in other countries. Our observations stress the need for MRSA surveillance in the Czech Republic in order to monitor changes in MRSA epidemiology.

[Practical experience with the detection Clostridium difficile]. / Praktické zkusenosti s diagnostikou Clostridium difficile.

Clostridium difficile is an important pathogen causing nosocomial diarrhoea and colitis which, in severe cases, may result in pseudomembranous colitis and eventually death. The main pathogenicity factors for C. difficile are toxins referred to as A and B. The diagnosis of diseases caused by C. difficile is based on detection of the toxins, together with culture and determination of susceptibility of C. difficile strains to antibiotics. The article reports results of tests of kits for detecting C. difficile toxins VIDAS(c) C. difficile Toxin A & B (bioMérieux) and Toxin A Test (Oxoid) in 170 stool samples. Also reported are results of the determination of MICs of vancomycin and metronidazole in 302 strains of C. difficile cultured in the bacteriology laboratory of the Institute of Public Health in Ostrava in 2008-2009.

[Prevalence of ESBL-positive enterobacteriaceae in large moravian hospitals (Czech Republic)]. / Prevalence ESBL-pozitivních enterobakterií ve velkých moravských nemocnicích.

BACKGROUND: bacterial infections have become an important issue in current medicine. Recently, their frequency and severity have significantly increased as a result of the rising number of resistant bacteria. One of important mechanisms of resistance is production of broad-spectrum beta-lactamases, namely the ESBL type. The study aimed at determining the frequency of ESBL-positive Enterobacteriaceae in three large hospitals in Moravia, the eastern part of the Czech Republic. MATERIAL AND METHODS: enterobacteriaceae were isolated from clinical material obtained from patients hospitalized in the University Hospital Olomouc, Teaching Hospital Ostrava and Bata Regional Hospital Zlín throughout 2009. Standard microbiology techniques were used for identification. The production of ESBLs was determined by the modified Double-Disk Synergy Test. ESBL-positive isolates of Escherichia coli from ICU patients were subjected to basic genetic analysis. RESULTS AND CONCLUSION: during the study period, a total of 12,922 strains from the Enterobacteriaceae family were detected. The ESBL phenotype was found in 907 cases, i.e. 7 % of all isolates. The most prevalent species of ESBL-producing Enterobacteriaceae were Klebsiella pneumoniae, Klebsiella oxytoca and Escherichia coli. A comparison of general wards and ICUs revealed a higher percentage of ESBL-positive strains of Klebsiella pneumoniae and a lower proportion of ESBL-positive Escherichia coli isolates in intensive care patients. When assessing the patients' clinical material, ESBL-producing strains were most frequently detected in urine. Genetic analysis of ESBL-positive Escherichia coli strains from ICU patients revealed the CTX-M type of ESBL production in most isolates.

Antimicrobial susceptibility of Gram-negative and Gram-positive bacteria collected from Eastern Europe: Results from the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.), 2011-2016.

OBJECTIVES: The Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) is a global surveillance programme monitoring the in vitro activity of a panel of antimicrobial agents against clinically important bacterial isolates. Data for Gram-positive and Gram-negative isolates collected in Eastern Europe between 2011 and 2016 are presented here. METHODS: Minimum inhibitory concentrations (MICs) were determined by the broth microdilution method using CLSI guidelines. Antimicrobial susceptibility was assessed using EUCAST breakpoints. RESULTS: Nine Eastern European countries submitted 4289 isolates. Among Acinetobacter baumannii, resistance to levofloxacin, amikacin and meropenem was 77.5%, 63.4% and 62.2%, respectively. Multidrug resistance among A. baumannii was higher in 2015 than in previous years (44.1% in 2011 and 71.0% in 2015), decreasing to 51.7% in 2016. The multidrug resistance percentage for Pseudomonas aeruginosa was 26.9% and was relatively stable over time. The percentage of extended-spectrum ß-lactamase (ESBL)-positive isolates among Escherichia coli and Klebsiella pneumoniae was 20.1% and 55.7%, respectively. Resistance to amikacin, meropenem and tigecycline was low among E. coli and K. pneumoniae and the ESBL-producing subset (≤5.9%). Among Staphylococcus aureus isolates, 36.7% were methicillin-resistant (MRSA); percentages varied year-on-year. No S. aureus isolates, including MRSA, were resistant to linezolid, vancomycin or tigecycline. Among Enterococcus faecium isolates, resistance was 22.6% to vancomycin and 2.3% to linezolid; no isolates were resistant to tigecycline. CONCLUSION: This study shows low resistance to meropenem and tigecycline among Enterobacteriaceae isolates and continued activity of linezolid, vancomycin and tigecycline against Gram-positive organisms. However, antimicrobial resistance continues to be problematic in Eastern Europe and requires continued surveillance.

[Prevalence of ESBL-positive strains of Klebsiella pneumoniae in the Czech Republic and their molecular biology analysis]. / Prevalence ESBL-pozitivních kmenu Klebsiella pneumoniae v Ceské republice a jejich molekulárne-biologická analýza.

BACKGROUND: One of the problems of contemporary medicine is an increasing number of bacterial strains with hazardous phenotypes of resistance. The feared bacterial pathogens include Klebsiella pneumoniae strains producing AmpA extended-spectrum beta-lactamases. The study focused on the molecular biological characteristics of ESBL-positive strains of Klebsiella pneumoniae collected in the Czech Republic. MATERIALS AND METHODS: Clinical material from patients hospitalized in 16 Czech hospitals in September and October 2004 was used to isolate and determine Klebsiella pneumoniae strains by standard identification procedures. Their susceptibility to antibiotics was tested using a dilution micromethod. A Double-Disk Synergy Test was used for phenotype determination of ESBL production. The blaTEM, blaSHV and blaOXA genes coding ESBL production were demonstrated by PCR. Molecular biological characteristics of ESBL-positive strains utilized the genomic DNA isolation, XbaI restrictase digestion and PFGE differentiation. The acquired restriction maps of individual isolates were compared using GelCompar II software and their relationship was determined. RESULTS: During the monitored period, 913 Klebsiella pneumoniae strains causing clinically detectable diseases were isolated. Of these, 234 (25.6 %) were determined as ESBL-positive strains. The prevalence of ESBL-positive strains was 38.5 % in ICUs and 15.8 % in standard wards. More than 50 % of ESBL-positive isolates were effectively treated only with meropenem (98 %), cefoperazone/sulbactam (61 %) and amikacin (54 %). Conversely, ESBL-negative strains showed high susceptibility to all tested antibiotics (76-99 %). The molecular biological analysis identified 18 clonal types containing 2-6 identical strains. 17 clones usually contained isolates from one hospital and only in one clone strains from two hospitals were identified. CONCLUSION: Based on the above mentioned results, the prevalence of ESBL-positive strains of Klebsiella pneumoniae in the Czech Republic can be perceived as relatively high, especially in the ICUs. An extensive spread of epidemic clones within Czech hospitals and, to a limited extent, between them can be demonstrated.

Global in vitro activity of tigecycline and linezolid against Gram-positive organisms collected between 2004 and 2009.

This study reports the antimicrobial activity of tigecycline and comparator antimicrobials, including linezolid, against Staphylococcus aureus, Streptococcus pneumoniae, Enterococcus faecalis and Enterococcus faecium collected as part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) between 2004 and 2009. Minimum inhibitory concentrations (MICs) were determined using broth microdilution methodology according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Antimicrobial susceptibility was determined according to CLSI criteria. For tigecycline, the US Food and Drug Administration (FDA)-approved criteria were used. Overall, 41.3% (8249/19 982) of S. aureus collected were meticillin-resistant S. aureus (MRSA). All MRSA were susceptible to linezolid and 99.98% were susceptible to tigecycline. A total of 2.3% of E. faecalis (201/8576) and 39.7% of E. faecium (1226/3088) were vancomycin-resistant. Linezolid and tigecycline MIC(90) values (MIC at which 90% of isolates inhibited) against the Enterococcus spp. were 2mg/L and ≤ 0.25 mg/L, respectively. All S. pneumoniae [including 6.2% (599/9618) penicillin-non-susceptible] were susceptible to linezolid and vancomycin; tigecycline MIC(90) values were ≤ 0.12 mg/L. This report demonstrates the continuing good activity of tigecycline and linezolid against Gram-positive isolates globally, including resistant organisms such as MRSA, vancomycin-resistant enterococci and penicillin-resistant S. pneumoniae, with antimicrobial activity maintained over the 6 years of isolate collection.