[Antimicrobial susceptibility of Yersinia enterocolitica and Yersinia pseudotuberculosis strains isolated from humans in Poland during 2004-2009]. / Ocena wrazliwosci na wybrane antybiotyki paleczek Yersinia enterocolitica i Yersinia pseudotuberculosis izolowanych z próbek materialu klinicznego w Polsce w latach 2004-2009.

The number of yersiniosis has increased in the last few years in Poland, especially an increase of Yersinia enterocolitica bioserotype 1B/O:8 infections was observed. From 2004 to 2009 265 of Y. enterocolitica 4/O:3, 108 of Y. enterocolitica 1B/O:8, 8 of Y. enterocolitica 2/O:9 and 4 of Y. pseudotuberculosis clinical isolates were collected. To obtain basic data for resistance monitoring purpose 385 Yersinia strains were tested by standard disc diffusion method for their susceptibilities to 12 antimicrobial agents. In addition beta-lactamase (enzyme A) inhibition assays were undertaken with ticarcillin and clavulanic acid and beta-lactamase (enzyme B) induction tests were perfonned with imipenem as the inducer for 135 strains. The present study demonstrated a high susceptibility of clinical strains to most of the tested antibiotics with the exception of ampicillin, ticarcillin and streptomycin. No strains were resistant to third-generation cephalosporins, fluoroquinolones, gentamicin and tetracyclin. Less than 10% isolates were resistant to amoxicillin with clavulanic acid (except--all Y. enterocolitica 2/O:9 strains were resistant), sulfonamide, trimetoprim/sulfamethoxazole and chloramphenicol. Four isolates of Y. enterocolitica 4/O:3 and one Y. enterocolitica 2/O:9 was multidrug resistant (MDR). Detection of enzyme A by disc diffusion in all tested strains, with the exception of the three Y. pseudotubeculosis I isolates, was highly reliable but results of enzyme B detection by the disc diffusion test were, especially for Y. enterocolitica 1B/O:8, faced with the difficulties.

[Characterization of first sorbitol-fermenting shiga toxin-producing Escherichia coli O157:H- strain isolated in Poland]. / Charakterystyka pierwszego izolowanego w Polsce fermentujacego sorbitol werotoksycznego szczepu Escherichia coli O157.

Sorbitol-fermenting shiga toxin-producing E. coli O157:H- strains have emerged as a cause of human disease in many European and non-European countries. The role of SF VTEC O157:H- in the etiology of pediatric HUS and diarrhea is significant. We characterized the first SF VTEC O157:H- strain isolated from 9 year old patient in Poland. Strain possessed many traits characteristics for SF VTEC O157:H-. It fermented sorbitol after overnight incubation and produced beta-glucuronidase. It possessed the stx2, eae-gamma, EhlyA and sfpA genes and did not harbour plasmid-encoded katP and espP genes. Motility was not expressed but the strain possessed the chromosomal fliC locus for H7 antigen. The spread of SF VTEC O157:H- strains demonstrates the need for appropriate procedures for their microbiological diagnosis in Poland.

Serum immunoglobulin IgG subclass distribution of antibody responses to Yop proteins and lipopolysaccharide of Yersinia enterocolitica in patients with yersiniosis.

To assess the humoral immunological responses at the IgG subclass level in yersiniosis specific antibody responses against lipopolysaccharide of Yersinia enterocolitica 03 (LPS) and Yersinia Yop proteins were analyzed by ELISA. Thirty five patients with arthritis and forty nine patients with uncomplicated yersiniosis were included in the study. Analysis of the IgG subclass responses to the LPS revealed that the subclass distribution for both groups of patients was IgG2>IgG1>IgG3. The concentration of IgG4 was below detection level. The predominant antibody responses to Yop proteins were IgG1>IgG3>IgG2>IgG4 but the frequency of detection of particular IgG subclass antibodies were dependent on the age of patients. Generally, the frequency of occurrence of IgG2 antibodies for Yop proteins of Yersinia together increased with age reaching its peak among individuals aged above 40 years. On the other hand, IgG1 for Yop proteins and IgG3 for Y. enterocolitica LPS were diagnosed more often in serum samples obtained from children than from adults. We also found significantly higher frequency of IgG4 to Yop proteins of Y. enterocolitica in men than in women.

[Enzyme-linked immunosorbent assay in the diagnosis of campylobacteriosis]. / Wykorzystanie odczynu elisa w serologicznej diagnostyce kampylobakteriozy.

Campylobacter jejuni and Campylobacter coli are the bacterial cause of human gastroenteritis commonly reported worldwide. The serodiagnosis of Campylobacter infections is not routinely done in Poland so the aim of this study was to evaluation of ELISA in the diagnosis ofcampylobacteriosis. Serum samples obtained from 145 patients with gastroenteritis were tested by ELISA with 7 different heat-stable antigens of C. jejuni and one of C. coli and by the commercial Virion/Serion ELISA with purified 45 kDa outer membrane protein of C. jejuni. Antibodies for heat-stable antigens of C. jejuni were detected statistically more often than antibodies for heat-stable antigens of C. coli and for purifled protein of C. jejuni. We found significant differences in the frequency of detection of antibodies to different heat-stable antigens, ranged from 18.6% to 68.9% of positive results, what indicate for serological heterogenicity of C. jejuni strains isolated in Poland. The results of our study showed usefulness of ELISA in serological diagnosis of campylobacteriosis. However it is necessary to serotype the C. jejuni strains isolated in Poland to find the appropriate C. jejuni serotype for using in ELISA.

Clonal structure of Enterococcus faecalis isolated from Polish hospitals: characterization of epidemic clones.

To study the population structure of Enterococcus faecalis from Polish hospitals, 291 isolates were typed by pulsed-field gel electrophoresis and a novel multilocus sequence typing scheme (P. Ruiz-Garbajosa et al., J. Clin. Microbiol. 44:2220-2228, 2006). The isolates originated from geographically widespread medical institutions and were recovered during a 10-year period (1996 to 2005) from different clinical sources. The analysis grouped the isolates into five epidemic and 71 sporadic clones. The importance of the previously identified global clonal complexes CC2 and CC9 was corroborated by our findings that two of the Polish epidemic clones, A and J, were classified into these clonal complexes (CCs). However, the two most predominant clones, C (ST40) and F (CC87), did not cluster in the aforementioned CCs and may represent novel epidemic CCs. These clones may have emerged in Central Europe. Clone F, carrying glycopeptide resistance determinants of VanA or VanB phenotypes, caused several outbreaks in hematology units and appeared to be the most prevalent clone in recent years in Poland. Antimicrobial susceptibility testing and additional tests for pathogenicity-related phenotypes (hemolysin and gelatinase production) and genes (asa1 and esp) were performed to further characterize these epidemic clones. Multidrug resistance, glycopeptide resistance, presence of asa1, and production of hemolysin appeared to be statistically significant features related to epidemicity. Production of gelatinase was significant for two of the epidemic clones, whereas presence of the esp gene was not specific for the epidemic clones.