Antibiotic Resistance, spa Typing and Clonal Analysis of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates from Blood of Patients Hospitalized in the Czech Republic.

Staphylococcus aureus is one of the major causes of bloodstream infections. The aim of our study was to characterize methicillin-resistant Staphylococcus aureus (MRSA) isolates from blood of patients hospitalized in the Czech Republic between 2016 and 2018. All MRSA strains were tested for antibiotic susceptibility, analyzed by spa typing and clustered using a Based Upon Repeat Pattern (BURP) algorithm. The representative isolates of the four most common spa types and representative isolates of all spa clonal complexes were further typed by multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing. The majority of MRSA strains were resistant to ciprofloxacin (94%), erythromycin (95.5%) and clindamycin (95.6%). Among the 618 strains analyzed, 52 different spa types were detected. BURP analysis divided them into six different clusters. The most common spa types were t003, t586, t014 and t002, all belonging to the CC5 (clonal complex). CC5 was the most abundant MLST CC of our study, comprising of 91.7% (n = 565) of spa-typeable isolates. Other CCs present in our study were CC398, CC22, CC8, CC45 and CC97. To our knowledge, this is the biggest nationwide study aimed at typing MRSA blood isolates from the Czech Republic.

Epidemiological characteristics of methicillin-resistant Staphylococcus aureus isolates from bloodstream cultures at University Hospital in the Czech Republic.

The aim of this study was to trace the dynamic changes of methicillin-resistant Staphylococcus aureus (MRSA) lineages in the local hospital in both the national and international context. We describe genotypic and phenotypic characterization of 62 non-duplicate MRSA isolates collected during 2010-2016 at University Hospital in Hradec Kralove, Czech Republic. The isolates were characterized by multilocus sequence typing (MLST), spa typing, and staphylococcal cassette chromosome mec typing (SCCmec typing). Eight different genotypes were described; ST225-t003-II (32/62, 52%), ST5-t002-II (13/62, 22%), and ST225-t014-II (12/62, 21%) were constantly detected over the 7-year follow-up period. The genotypes ST225-t151-II, ST225-t1282-II, ST225-t1623-II, ST78-t2832-II, and ST225-t8799-II occurred only once in the period reported. The majority of the strains, represented by ST225, belonged to clonal complex 5 (CC5).

The association of pili with the emergence and replacement of the major antibiotic resistant pneumococcal clones.

BACKGROUND: The aim of this study was to evaluate the presence of pilus islet 1 (PI-1) and to determine its clade type in pneumococcal isolates with reduced susceptibility to penicillin (penicillin non-susceptible pneumococci - PNSP) and/or resistant to macrolides isolated prior to and after the introduction of pneumococcal conjugate vaccines (PCVs) in the Czech Republic. METHODS: Clinical isolates of serotypes 9V (n = 68) and 19A (n = 89) were examined. Isolates were characterised by multilocus sequence typing (MLST). The presence of PI-1 was determined by screening for the sortase B, C, and D genes located within PI-1. In the presence of PI-1 pilus, clade types were classified by PCR. RESULTS: In the pre-PCV period (2000-2007), the prevalence of PNSP was 3.9% and 2.7% of isolates were resistant to erythromycin. During 2012-2015 (post-PCV period), the rates of PNSP remained stable (3.6%), but resistance to erythromycin increased to 8.3%. While in 2000-2007, resistance to antibiotics was associated mainly with serotype 9V, in 2012-2015, it was replaced by serotype 19A. PI-1 positive isolates were seen in both serotypes. All isolates (68) of serotype 9V belonged to the Spain9V-3 (CC156) clone and carried PI-1 of clade type I while 96.5% (56/58) of isolates of 19A serotype belonged to the Netherlands15B-37 (CC199) clone and carried PI-1 of clade type II. CONCLUSIONS: Both major antibiotic resistant clones carried PI-1, although they differ in the clade type. Thus the role of PI-1 should be evaluated in further studies and potentially considered in the spread of antibiotic resistant clones.

[Antimicrobial activity of ceftolozane/tazobactam against Enterobacteriaceae and Pseudomonas aeruginosa in the Czech Republic in 2016].

OBJECTIVE: Ceftolozane/tazobactam is an antibiotic effective against Gram-negative bacteria(including Pseudomonas aeruginosa).The study aimed at determining the effectiveness of the novel antibiotic in the Czech Republic. MATERIAL AND METHODS: The effectiveness of the antibiotic was studied in 16 Czech laboratories in 822 Enterobacteriaceae isolates (including AmpC and ESBL producers) and P. aeruginosa causing complicated intraabdominal or urinary tract infections. Minimum inhibitory concentrations were determined using the Etest. With the exception of Citrobacter freundii and Enterobacter cloacae, ceftozolane/tazobactam proved to be very effective against Enterobacteriaceae; no P. aeruginosa strain was resistant to the antibiotic. CONCLUSION: The results confirmed good activity of ceftozolane/tazobactam in vitro against Enterobacteriaceae (Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis) and P. aeruginosa in the Czech Republic.

KPC-2-producing Klebsiella pneumoniae isolated from a Czech patient previously hospitalized in Greece and in vivo selection of colistin resistance.

Carbapenemase-producing Gram-negative bacteria peak clinical interest due to their ability to hydrolyze most ß-lactams, including carbapenems; moreover, their genes spread through bacterial populations by horizontal transfer. Bacteria with acquired carbapenemase have sporadically been reported in the Czech Republic, so far only in Enterobacteriaceae and Pseudomonas aeruginosa. In this study, we described the first finding of a KPC-2-producing strain of Klebsiella pneumoniae, which was isolated from a surgical wound swab, decubitus ulcer, and urine of a patient previously hospitalized in Greece. The patient underwent various antibiotic therapies including a colistin treatment. However, after approximately 20 days of the colistin therapy, the strain developed a high-level resistance to this drug. All the isolates were indistinguishable by pulsed field gel electrophoretic analysis and belonged to the international clone ST258, which is typical of KPC-producing K. pneumoniae isolates. The bla (KPC-2) gene was located on a Tn4401a transposon variant. The OmpK35 and OmpK36 genes analysis performed due to the high resistance level of the strains to ß-lactams exhibited no changes in their sequence or in their expression when compared with carbapenem-susceptible isolates.