Molecular characteristics of KPC-producing Enterobacteriaceae at the early stage of their dissemination in Poland, 2008-2009.

After the first report in May 2008, the National Reference Center for Susceptibility Testing confirmed 113 cases of infection or colonization by KPC-producing members of the family Enterobacteriaceae in Poland by the end of 2009. The vast majority of patients were found in 18 hospitals; three patients were diagnosed at outpatient clinics. Most of the institutions were in the Warsaw area, including three hospitals with the highest numbers of cases. When available, the data on previous hospitalizations often indicated that these hospitals were the probable acquisition sites; one patient arrived from New York. The group of 119 unique isolates consisted of Klebsiella pneumoniae (n = 114), followed by Klebsiella oxytoca (n = 3), and Escherichia coli (n = 2). The K. pneumoniae isolates were dominated by the clone sequence type 258 (ST258) (n = 111); others were ST11 and ST23. The ST258 group was heterogeneous, with 28 pulsed-field gel electrophoresis (PFGE) subtypes, ∼25 plasmid profiles, and nine ß-lactamase patterns differing by KPC variants (KPC-2 mainly), and SHV-12, CTX-M-3, and TEM-1-like enzymes. Plasmids carrying bla(KPC) genes varied in size (~48 to 250 kb), structure, and conjugation potential. Transferable IncFII(K) plasmids of ~110 to 160 kb, probably pKpQIL or its derivatives, were observed in all K. pneumoniae clones and in K. oxytoca. Also prevalent were nontypeable pETKp50-like plasmids of ~50 kb, found in K. pneumoniae ST258 and E. coli isolates (ST93 and ST224). Two K. pneumoniae-E. coli pairs from single patients might represent the in vivo transfer of such plasmids. The striking diversity of KPC producers at the early stage of dissemination could result from several introductions of these bacteria into the country, their multidirectional evolution during clonal spread, and transfer of the plasmids.

[Susceptibility of Escherichia coli strains isolated from persons with urinary tract infections in 2007 - 2008 to antimicrobial agents]. / Wrazliwosc na antybiotyki i chemioterapeutyki szczepów Escherichia coli wyizolowanych od osób z zakazeniami ukladu moczowego w latach 2007 - 2008.

OBJECTIVE: Determination of sensitivity to antibiotics and chemotherapeutics of 160 E. coli strains isolated from 2007 to 2008 from cases of hospital urinary tract infections and assessment the ability to produce ESBL by these strains. METHODS: The susceptibility of E. coli strains to ampicillin, amikacin, amoxicillin with clavulanic acid, aztreonam, cephalothin, cefotaxime, ceftazidime, cefuroxime, ciprofloxacin, ertapenemem, gentamicin, imipenem, meropenemem, nitrofurantoin, piperacillin, piperacillin with tazobactam, tetracycline, and trimethoprim with sulfamethoxazole was tested by using a disc-diffusion method. Ability to producing ESBL was detected by using double disc synergy test. RESULTS: The analysis revealed a high percentage of strains resistant to ampicillin (56.8%). Strains showing resistance to tetracycline (35%), trimethoprim with sulfamethoxazole (23.1%), ciprofloxacin (19.4%), gentamicin (3.75%) and nitrofurantoin (3.75%) were also obtained. The percentage of strains resistant to amoxicillin with clavulanic acid among those isolated in 2007 was 2.9%, and in group of strains obtained in 2008 was 20.6%. Production of ESBL was observed in 4.4% of strains, which in addition to resistance to penicillin and cephalosporins showed resistance to antibiotics belonging to other groups. Multi-drug resistant strains were also obtained, which did not produce ESBL. CONCLUSIONS: Increasing resistance to some of the antibiotics and the emergence of multi-drug resistant strains clearly indicate the need for continuous monitoring of antibiotic susceptibility in uropathogenic E. coli strains.