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.

First report of Sneathia sanguinegens together with Mycoplasma hominis in postpartum prosthetic valve infective endocarditis: a case report.

BACKGROUND: The presence of more than one bacterial agent is relatively rare in infective endocarditis, although more common in prosthetic cases. Molecular diagnosis from a removed heart tissue is considered a quick and effective way to diagnose fastidious or intracellular agents. CASE PRESENTATION: Here we describe the case of postpartum polymicrobial prosthetic valve endocarditis in a young woman. Sneathia sanguinegens and Mycoplasma hominis were simultaneously detected from the heart valve sample using broad range 16S rRNA polymerase chain reaction (PCR) followed by sequencing while culture remained negative. Results were confirmed by independent PCR combined with denaturing gradient gel electrophoresis. Before the final agent identification, the highly non-compliant patient left from the hospital against medical advice on empirical intravenous treatment with aminopenicillins, clavulanate and gentamicin switched to oral amoxycillin and clavulanate. Four months after surgery, no signs of inflammation were present despite new regurgitation and valve leaflet flail was detected. However, after another 5 months the patient died from sepsis and recurrent infective endocarditis of unclarified etiology. CONCLUSIONS: Mycoplasma hominis is a rare causative agent of infective endocarditis. To the best of our knowledge, presented case is the first report of Sneathia sanguinegens detected in this condition. Molecular techniques were shown to be useful even in polymicrobial infective endocarditis samples.

[The current problems related to nosocomial infections and antibiotic resistance today]. / Nozokomiální infekce a antibiotická rezistence v soucasnosti.

Nosocomial, also known as hospital acquired infections, are today considered to be an important indicator of the quality of health care in all health establishments. They involve an undesirable complication of the provided health care with a number of negative consequences, such as increased morbidity and mortality, longer time of hospitalization and higher costs. Their incidence at present is also related, among other things, to the broadening, sometimes invasive technical possibilities of diagnosing and therapy. Another issue in Czech hospitals consists in the growing resistance of some bacteria to antibiotics. In practice this means considerably limited possibilities of treatment. The contribution brings the current data about the state of bacterial resistance in Czech hospitals (European project EARS-Net - year 2015).Key words: bacterial resistance - European Antimicrobial Resistance Surveillance Network (EARS-Net) - health care related infections - hospital-acquired infections.

The association of a reduced susceptibility to moxifloxacin in causative Clostridium (Clostridioides) difficile strain with the clinical outcome of patients.

OBJECTIVES: To investigate the relationship between Clostridium (Clostridioides) difficile strain characteristics and C. difficile infection (CDI) outcome. METHODS: Between October and December 2017, 16 hospitals collected epidemiological data according to the European Centre for Disease Prevention and Control (ECDC) surveillance protocol for CDI. C. difficile isolates were characterized by ribotyping, toxin genes detection and antibiotic susceptibility testing to metronidazole, vancomycin and moxifloxacin. RESULTS: The overall mean CDI incidence density was 4.5 [95% CI 3.6-5.3] cases per 10,000 patient-days. From the 433 CDI cases, 330 (76.2%) were healthcare-associated, 52 (12.0%) cases were community-associated or of unknown origin and 51 (11.8%) CDI cases recurrent; a complicated course of CDI was reported in 65 cases (15.0%). Eighty-eight (20.3%) of patients died and 59 of them within 30 days after the CDI diagnosis. From the 379 C. difficile isolates, the most prevalent PCR ribotypes were 001 (n = 127, 33.5%) and 176 (n = 44, 11.6%). A total of 186 (49.1%) isolates showed a reduced susceptibility to moxifloxacin (> 4 mg/L) and 96.4% of them had Thr82Ile in the GyrA. Nineteen isolates revealed reduced susceptibility to metronidazole and two isolates to vancomycin (> 2 mg/L). A fatal outcome was associated with a reduced susceptibility to moxifloxacin, the advanced age of the patients and a complicated course of CDI (p<0.05). No association between ribotype, binary toxin and a reduced susceptibility to moxifloxacin and complicated course or recurrent CDI was found. CONCLUSIONS: A reduced susceptibility to moxifloxacin, in causative C. difficile strains was associated with fatal outcome of the patients, therefore it is an important marker in surveillance of CDI.

Two Clusters of Fluoroquinolone and Clindamycin-Resistant Clostridium difficile PCR Ribotype 001 Strain Recognized by Capillary Electrophoresis Ribotyping and Multilocus Variable Tandem Repeat Analysis.

AIM: To perform a retrospective analysis of the high occurrence of Clostridium difficile infection in the surgical department of a Czech tertiary care hospital and to identify weaknesses in C. difficile infection (CDI) prevention and control policies. METHODS: Clinical and epidemiological data on eleven CDI cases were collected. C. difficile isolates were characterized by capillary electrophoresis ribotyping, multilocus variable tandem repeat analysis (MLVA), gyrA gene fragment sequencing, and erm(B) fragment PCR amplification. Antibiotic susceptibility to metronidazole, vancomycin, ciprofloxacin, moxifloxacin, and clindamycin was tested. FINDINGS: Eleven CDI cases were caused by C. difficile PCR ribotype 001 strains. These strains revealed two different MLVA profiles with 11 tandem repeat differences. All isolates were susceptible to metronidazole and vancomycin and resistant to ciprofloxacin (MIC ≥32 mg/L), moxifloxacin (MIC ≥32 mg/L), and clindamycin (MIC ≥256 mg/L). All isolates revealed amino acid substitution Thr82Ile, in the GyrA and were erm(B) negative. CONCLUSION: Two fluoroquinolone and clindamycin-resistant C. difficile PCR ribotype 001 strain clusters occurred at one of the surgical departments of a tertiary care hospital. Ineffective decontamination with suboptimal concentration and time of exposure of sporicidal disinfectants may have resulted in C. difficile transmission.

[Determination of sensitivity of biofilm-positive forms of microorganisms to antibiotics]. / Stanovení citlivosti k antibiotikum u biofilmpozitivních forem mikrooganizmu.

Nosocomial infections caused by biofilm-positive microorganisms are a serious therapeutic problem. In the biofilm, microorganisms are protected against adverse effects of the external environment, including the action of antibiotics. It is well known that the values of minimum inhibitory concentrations (MIC) determined for planktonic forms do not correspond to the actual concentrations of antibiotics necessary for the eradication of bacteria in a biofilm. The purpose of the study was to propose a method of determining minimum biofilm inhibitory concentrations (MBIC) and minimum biofilm eradication concentrations (MBEC) and to compare these values with MIC values. Biofilm-positive strains of Staphylococcus epidermidis were cultured so as to form a biofilm layer on polystyrene pegs. The biofilm on the pegs was then exposed to the action of antibiotics and after 18 hours we determined the minimum biofilm inhibitory concentration (MBIC). The evaluation of minimum biofilm eradication concentrations was done colorimetrically from the metabolic activity of surviving cells. MBIC and MBEC values were many times higher than MIC values. We selected such a duration of the biofilms cultivation on the pegs of the plate, which ensured that the number of bacterial cells corresponded to standard MIC assessment. The MBEC values established in our study indicate that the currently used concentrations of tested antibiotics cannot be used in monotherapy for an efficacious eradication of a biofilm. The MBEC determination is a far more laborious and time-consuming method than the determination of MIC, but the use of plates with pegs facilitates the handling of biofilms. The advantage of our method is the possibility of standardization of the size of the inoculum and thus of the whole MBEC assessment.