Waleria Hryniewicz

Publications of Waleria Hryniewicz

• Insight into antimicrobial susceptibility and population structure of contemporary human Enterococcus faecalis isolates from Europe.

  Authors: Alicja Kuch, Rob J L Willems, Guido Werner, Teresa M Coque, Anette M Hammerum, Arnfinn Sundsfjord, Ingo Klare, Patricia Ruiz-Garbajosa, Gunnar S Simonsen, Miranda van Luit-Asbroek, Waleria Hryniewicz, Ewa Sadowy

  The Journal of antimicrobial chemotherapy. 12/2011; 67(3):551-8.

  To investigate antimicrobial susceptibility and clonal relatedness of Enterococcus faecalis human isolates recovered recently (2006-09) in six European countries. Antimicrobial susceptibility of 386To investigate antimicrobial susceptibility and clonal relatedness of Enterococcus faecalis human isolates recovered recently (2006-09) in six European countries. Antimicrobial susceptibility of 386 isolates from Denmark, Germany, Norway, Poland, Spain and The Netherlands, from hospital infections (223 isolates), carriage (82 isolates) and from colonization in the community (81 isolates) was determined by the broth microdilution method. Clonal relatedness of isolates was assessed by multilocus sequence typing. All isolates were susceptible to benzylpenicillin, ampicillin, linezolid, tigecycline and daptomycin. Non-susceptibility to tetracycline (77.6%), rifampicin (57.3%), ciprofloxacin (51.2%), aminoglycosides (43.3% high-level gentamicin resistance, 40.0% high-level streptomycin resistance) was frequent among hospital isolates, while non-susceptibility to glycopeptides was rare and associated mostly with vanA. Multidrug resistance was found in 59.7% of hospital isolates and 16.1% of community isolates. Isolates were classified into 105 sequence types (STs), of which 21 STs, representing more than half of the collected isolates (53.9%), grouped with 6 large E. faecalis clonal complexes (CCs; CC2, CC16, CC21, CC30, CC40 and CC87). Two of these, CC2 (frequently recovered in Spain and The Netherlands) and CC87 (prevalent in Poland), were found almost exclusively in hospitals and included the highest proportion of multiresistant isolates. While hospital-acquired E. faecalis in Europe remains susceptible to ampicillin and glycopeptides, the high prevalence of strains that are highly resistant to aminoglycosides excludes these antibiotics from combination therapies. Genotyping revealed that nosocomial infections by multiresistant E. faecalis are largely caused by only a few hospital-associated clones.

• Efficiency of the Cepheid Xpert vanA/vanB assay for screening of colonization with vancomycin-resistant enterococci during hospital outbreak.

  Authors: Dorota Zabicka, Janusz Strzelecki, Agnieszka Wozniak, Pawel Strzelecki, Ewa Sadowy, Alicja Kuch, Waleria Hryniewicz

  Antonie van Leeuwenhoek. 11/2011; 101(3):671-5.

  This study aimed to assess the efficiency of the Cepheid Xpert vanA/vanB test for detecting vancomycin-resistant enterococci (VRE) colonization during a VanA Enterococcus faecium outbreak and toThis study aimed to assess the efficiency of the Cepheid Xpert vanA/vanB test for detecting vancomycin-resistant enterococci (VRE) colonization during a VanA Enterococcus faecium outbreak and to compare the Cepheid Xpert vanA/vanB (Cepheid, Sunnyvale, USA) test to a culture method with chromogenic medium chromID VRE agar (bioMérieux). The Cepheid Xpert vanA/vanB assay showed sensitivity 61.5%, specificity 79.2%, positive predictive value 61.5% and negative predictive value 79.2%. The results obtained in this study demonstrate that a positive result in the Cepheid Xpert vanA/vanB test for vanA enables the rapid (less than 1 h) presumptive, prior to culture, recognition of patients colonized with VRE. However, the Cepheid Xpert vanA/vanB assay cannot be the only test used to screen patients during an ongoing VRE outbreak, because additional culturing of all samples negative for both vanA and vanB or positive for vanB should be performed in order to confirm the carrier status of the patient.

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

  Authors: Anna Baraniak, Anna Grabowska, Radosław Izdebski, Janusz Fiett, Małgorzata Herda, Katarzyna Bojarska, Dorota Żabicka, Marta Kania-Pudło, Grazyna Młynarczyk, Zofia Żak-Puławska, Waleria Hryniewicz, Marek Gniadkowski

  Antimicrobial agents and chemotherapy. 09/2011; 55(12):5493-9.

  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 EnterobacteriaceaeAfter 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 β-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.

• Multilocus variable number tandem repeat analysis (MLVA) of Streptococcus pyogenes.

  Authors: Katarzyna Obszańska, Anna L Borek, Radosław Izdebski, Waleria Hryniewicz, Izabela Sitkiewicz

  Journal of microbiological methods. 09/2011; 87(2):143-9.

  We tested 21 polymorphic loci encoded by the genome of Streptococcus pyogenes (group A Streptococcus, GAS). Seven of them were chosen for the MLVA scheme. The primer pairs, designed for selectedWe tested 21 polymorphic loci encoded by the genome of Streptococcus pyogenes (group A Streptococcus, GAS). Seven of them were chosen for the MLVA scheme. The primer pairs, designed for selected loci, detect from few to several alleles, and the method has a Simpson's Index of diversity of 0.957. To test the overall performance of the method, multiplex PCR reactions were carried out for over 700 GAS strains. Using the method we were able to detect differences between highly clonal strains that share the same emm, MLST and PFGE types. The most diverse strains were M4, M2, M3 and M28. We developed a typing method that can be employed to differentiate between GAS strains. The method has high resolution and measures diversity of the GAS core chromosome, on the contrary to methods such as PFGE.

• [Invasive pneumococcal disease in Poland in 2010].

  Authors: Anna Skoczyńska, Alicja Kuch, Agnieszka Gołebiewska, Izabela Waśko, Patrycja Ronkiewicz, Marlena Markowska, Waleria Hryniewicz

  Polski merkuriusz lekarski : organ Polskiego Towarzystwa Lekarskiego. 08/2011; 31(182):80-5.

  Streptococcus pneumoniae is the main etiologic agent of community-acquired invasive infections, especially in extreme age groups. Recently, the emergence of pneumococcal conjugate vaccines (PCV)Streptococcus pneumoniae is the main etiologic agent of community-acquired invasive infections, especially in extreme age groups. Recently, the emergence of pneumococcal conjugate vaccines (PCV) brought a possibility to reduce the number of pneumococcal infections. Their introduction requires a knowledge concerning epidemiology of infections, which in different part of the world differs and changes with time, and therefore must be under permanent surveillance. To characterize invasive pneumococcal disease (IPD) in Poland in 2010 based on data collected by the National Reference Centre for Bacterial Meningitis (NRCBM). The study was performed on all invasive S. pneumoniae isolates collected in 2010 by the NRCBM. All the strains were identified and serotyped based on routine techniques. Minimal inhibitory concentrations (MICs) were determined by the Etest or M.I.C. Evaluators method. For the incidence rate assessment, cases where the pneumolysin gene was detected by PCR in clinical material were included. The highest IPD incidence rates were among children under 5 years of age (3.43/100,000), and especially among children under 2 years of age (5.17/100,000). The vaccines PCV10 and PCV13 covered 54.9, and 75.4% of all IPD cases, 71.0 and 93.5% of cases among children under 2 years of age, and 71.2 and 92.3% among children under 5 years of age, respectively. Decreased susceptibility to penicillin (MIC > 0.06 mg/l) and cefotaxime (MIC > 0.5 mg/l) was found in 30.7 and 14.8% of isolates, respectively. All isolates were susceptible to rifampicin and vancomycin. Intermediate susceptibility and resistance to meropenem was notified in 6.1 and 5.7% of isolates. Resistance to chloramphenicol, erythromycin, clindamycin, tetracycline and co-trimoxazole was found in 8.0, 36.7, 29.9, 30.7 and 34.5% of isolates, respectively. Results of the study showed high theoretical coverage of pneumococcal conjugate vaccines among IPD cases in general and especially among infections caused by isolates with decreased susceptibility to antibiotics. Therefore, it seams that the best way to limit invasive pneumococcal disease-associated morbidity and mortality, especially of cases caused by bacteria with decreased susceptibility to antibiotics, is the inclusion of a PCV in the immunization programme in Poland.

• Characterization of transcription within sdr region of Staphylococcus aureus.

  Authors: Izabela Sitkiewicz, Ireneusz Babiak, Waleria Hryniewicz

  Antonie van Leeuwenhoek. 02/2011; 99(2):409-16.

  Staphylococcus aureus is an opportunistic pathogen responsible for various infections in humans and animals. It causes localized and systemic infections, such as abscesses, impetigo, cellulitis,Staphylococcus aureus is an opportunistic pathogen responsible for various infections in humans and animals. It causes localized and systemic infections, such as abscesses, impetigo, cellulitis, sepsis, endocarditis, bone infections, and meningitis. S. aureus virulence factors responsible for the initial contact with host cells (MSCRAMMs-microbial surface components recognizing adhesive matrix molecules) include three Sdr proteins. The presence of particular sdr genes is correlated with putative tissue specificity. The transcriptional organization of the sdr region remains unclear. We tested expression of the sdrC, sdrD, or sdrE genes in various in vitro conditions, as well as after contact with human blood. In this work, we present data suggesting a separation of the sdr region into three transcriptional units, based on their differential reactions to the environment. Differential reaction of the sdrD transcript to environmental conditions and blood suggests dissimilar functions of the sdr genes. SdrE has been previously proposed to play role in bone infections, whilst our results can indicate that sdrD plays a role in the interactions between the pathogen and human immune system, serum or specifically reacts to nutrients/other factors present in human blood.

• Comparison of multilocus variable-number tandem-repeat analysis with multilocus sequence typing and pulsed-field gel electrophoresis for Enterococcus faecalis.

  Authors: Ewa Sadowy, Aleksandra Sieńko, Waleria Hryniewicz

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2011; 60(4):335-9.

  Enterococcus faecalis represents recently an important etiological agent of health care-associated infections (HAIs) and there is a need for evaluation and comparison of typing methods available forEnterococcus faecalis represents recently an important etiological agent of health care-associated infections (HAIs) and there is a need for evaluation and comparison of typing methods available for this microorganism. We tested multilocus VNTR (variable-number tandem repeats) analysis (MLVA) on a well-characterized collection of 153 clinical isolates of E. faecalis, corresponding to 52 multilocus sequence types and 67 pulsed-field gel electrophoresis (PFGE) profiles. MLVA showed high discriminatory power, discerning 111 different types (diversity index equal 98.9%). The concordance MLVA/MLST and MLVA/PFGE was 0.95 and 0.74, respectively. High discriminatory power of MLVA indicates its utility for local epidemiology such as outbreak investigation, and for differentiation of clones defined by other methods.

• Gelatinase-associated phenotypes and genotypes among clinical isolates of Enterococcus faecalis in Poland.

  Authors: Janusz Strzelecki, Waleria Hryniewicz, Ewa Sadowy

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2011; 60(4):287-92.

  Enterococcus faecalis is an important nosocomial pathogen causing serious invasive infections. One of the virulence factors of this pathogen, gelatinase GelE, is a protease whose gene expression isEnterococcus faecalis is an important nosocomial pathogen causing serious invasive infections. One of the virulence factors of this pathogen, gelatinase GelE, is a protease whose gene expression is regulated by the Fsr quorum sensing system. In this study, we used a well-characterized collection of 153 clinical E. faecalis isolates to investigate the distribution of genes involved in gelatinase expression. Although 140 isolates (91% of the group) harbored the gelE gene, only 81 isolates (53%) produced active gelatinase. The gelatinase-negative phenotype was found in several unrelated clones, and appeared to be caused by various genetic events. Isolates of the hospital-adapted clonal complex 2 (CC2) and of CC40 were uniformly gelatinase-positive, while all the CC87 isolates contained the 23.9 kb deletion encompassing most of the fsr locus and were gelatinase-negative. No significant differences among isolates of different clinical origin and gelatinase activity or presence of the fsr genes were found with the exception of isolates from cerebrospinal fluid, which were more often gelatinase-positive than colonizing isolates.

• Staphylococcal cassette chromosome mec (Sccmec) classification and typing methods: an overview.

  Authors: Agata Turlej, Waleria Hryniewicz, Joanna Empel

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2011; 60(2):95-103.

  Meticillin-resistant Staphylococcus aureus (MRSA) is one of the main causes of hospital-acquired infections, but since late 1990s also the community-acquired. For better understanding of the S.aureusMeticillin-resistant Staphylococcus aureus (MRSA) is one of the main causes of hospital-acquired infections, but since late 1990s also the community-acquired. For better understanding of the S.aureus epidemiology there is an urgent need for creation of new typing method for SCCmec element. The molecular typing of MRSA for epidemiological purposes is investigated by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), spa typing and the SCCmec type assignment. In last few years not only new type of SCCmec (VI to XI) have been identified, but also additional subtypes (i.e. IVg-j) and different variants of already existed one (i.e. 5C2&5 and 2B2&5) were discovered. The aim of this review is to briefly summarize current knowledge about SCCmec classification and to discuss advantages and disadvantages of selected SCCmec typing methods.

• A new rapid and cost-effective method for detection of phages, ICEs and virulence factors encoded by Streptococcus pyogenes.

  Authors: Anna L Borek, Joanna Wilemska, Radosław Izdebski, Waleria Hryniewicz, Izabela Sitkiewicz

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2011; 60(3):187-201.

  Streptococcus pyogenes (group A Streptococcus, GAS) is a human pathogen that causes diseases of various intensity, from mild strep throat to life threatening invasive infections and postinfectionalStreptococcus pyogenes (group A Streptococcus, GAS) is a human pathogen that causes diseases of various intensity, from mild strep throat to life threatening invasive infections and postinfectional sequelae. S. pyogenes encodes multiple, often phage encoded, virulence factors and their presence is related to severity of the disease. Acquisition of mobile genetic elements, carrying virulence factors, as phages or ICEs (integrative and cojugative elements) has been shown previously to promote selection of virulent clones. We designed the system of eight low volume multi- and one singleplex PCR reactions to detect genes encoding twenty virulence factors (spd3, sdc, sdaB, sdaD, speB, spyCEP, scpA, mac, sic, speL, K, M, C, I, A, H, G, J, smeZ and ssa) and twenty one phage and ICE integration sites described so far for S. pyogenes. Classification of strains based on the phage and virulence factors absence or presence, correlates with PFGE MLST and emm typing results. We developed a novel, fast and cost effective system that can be used to detect GAS virulence factors. Moreover, this system may become an alternative and effective system to differentiate between GAS strains.

• The current status of invasive pneumococcal disease in Poland.

  Authors: Anna Skoczyńska, Ewa Sadowy, Katarzyna Bojarska, Janusz Strzelecki, Alicja Kuch, Agnieszka Gołębiewska, Izabela Waśko, Małgorzata Foryś, Mark van der Linden, Waleria Hryniewicz

  Vaccine. 10/2010; 29(11):2199-205.

  The objectives of this study were to assess the incidence of invasive pneumococcal disease (IPD) in Poland (2006-2009), where mass vaccination had not been implemented, and to determine the serotypeThe objectives of this study were to assess the incidence of invasive pneumococcal disease (IPD) in Poland (2006-2009), where mass vaccination had not been implemented, and to determine the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates. The IPD incidence rates were highest among children under 2 years of age (3.39/100,000 in 2009) and children 2-5 years old (2.44/100,000). The most common serotypes were 14, 3, 1, 4, 19F, 23F, 6B, and 12F (61.7% of all isolates). In children aged less than 5 years, isolates of serotypes 14, 6B, and 19F were most prevalent (52.7% of the IPD cases). The PCV7, PCV10, and PCV13 covered 43.3%, 54.8%, and 68.8% of all IPD cases, and 68.7%, 76.3%, and 86.3% of cases involving children under 5 years of age. Penicillin resistance was found in 21.3% of the isolates responsible for meningitis and in 1.2% of isolates responsible for other invasive infections. Introduction of antipneumococcal conjugated vaccines into the national immunisation programme would likely lead to a significant reduction of IPD-associated morbidity among Polish children in particular, as well as in the population as a whole, especially in cases involving pneumococci with a decreased susceptibility to antibiotics.

• First report of Streptococcus pneumoniae serotype 6D isolates from invasive infections.

  Authors: Alicja Kuch, Ewa Sadowy, Anna Skoczyńska, Waleria Hryniewicz

  Vaccine. 09/2010; 28(39):6406-7.

  We report the first invasive Streptococcus pneumoniae isolates of serotype 6D and the first occurrence of this serotype in Europe. Till now, the appearance of serotype 6D pneumococci inWe report the first invasive Streptococcus pneumoniae isolates of serotype 6D and the first occurrence of this serotype in Europe. Till now, the appearance of serotype 6D pneumococci in nasopharyngeal carriage has been speculated to be associated with a selective pressure from vaccination with the conjugated 7-valent antipneumococcal vaccine. Our observations indicate that this serotype is present also among unvaccinated individuals in the population where mass infant vaccination has not yet been introduced. Importantly, these strains were isolated from invasive infections, indicating the full virulence potential of pneumococci belonging to serotype 6D and its importance for future vaccine formulations.

• Multicenter study for defining the breakpoint for rifampin resistance in Neisseria meningitidis by rpoB sequencing.

  Authors: Muhamed-Kheir Taha, Sara Thulin Hedberg, Marek Szatanik, Eva Hong, Corinne Ruckly, Raquel Abad, Sophie Bertrand, Francoise Carion, Heike Claus, Alejandra Corso [......] Per Olcén, Marina Pana, Anna Skoczynska, Cecilia Sorhouet Pereira, Paola Stefanelli, Georgina Tzanakaki, Magnus Unemo, Julio A Vázquez, Ulrich Vogel, Izabela Wasko

  Antimicrobial agents and chemotherapy. 09/2010; 54(9):3651-8.

  Identification of clinical isolates of Neisseria meningitidis that are resistant to rifampin is important to avoid prophylaxis failure in contacts of patients, but it is hindered by the absence of aIdentification of clinical isolates of Neisseria meningitidis that are resistant to rifampin is important to avoid prophylaxis failure in contacts of patients, but it is hindered by the absence of a breakpoint for resistance, despite many efforts toward standardization. We examined a large number (n = 392) of clinical meningococcal isolates, spanning 25 years (1984 to 2009), that were collected in 11 European countries, Argentina, and the Central African Republic. The collection comprises all clinical isolates with MICs of > or = 0.25 mg/liter (n = 161) received by the national reference laboratories for meningococci in the participating countries. Representative isolates displaying rifampin MICs of < 0.25 mg/liter were also examined (n = 231). Typing of isolates was performed, and a 660-bp DNA fragment of the rpoB gene was sequenced. Sequences differing by at least one nucleotide were defined as unique rpoB alleles. The geometric mean of the MICs was calculated for isolates displaying the same allele. The clinical isolates displaying rifampin MICs of > 1 mg/liter possessed rpoB alleles with nonsynonymous mutations at four critical amino acid residues, D542, H552, S548, and S557, that were absent in the alleles found in all isolates with MICs of < or = 1 mg/liter. Rifampin-susceptible isolates could be defined as those with MICs of < or = 1 mg/liter. The rpoB allele sequence and isolate data have been incorporated into the PubMLST Neisseria database (http://pubmlst.org/neisseria/). The rifampin-resistant isolates belonged to diverse genetic lineages and were associated with lower levels of bacteremia and inflammatory cytokines in mice. This biological cost may explain the lack of clonal expansion of these isolates.

• Population structure, virulence factors and resistance determinants of invasive, non-invasive and colonizing Streptococcus agalactiae in Poland.

  Authors: Ewa Sadowy, Bozena Matynia, Waleria Hryniewicz

  The Journal of antimicrobial chemotherapy. 09/2010; 65(9):1907-14.

  To analyse Streptococcus agalactiae (group B Streptococcus; GBS) isolates collected in Poland from various human infections and carriage in respect of their clonality, distribution of virulenceTo analyse Streptococcus agalactiae (group B Streptococcus; GBS) isolates collected in Poland from various human infections and carriage in respect of their clonality, distribution of virulence factors and antimicrobial resistance determinants, including the detection of transposons involved in the dissemination of antimicrobial resistance. One hundred and fourteen GBS isolates were analysed by multilocus sequence typing (MLST), serotyping and detection of alp genes of the alpha-like-protein (Alp) family. Determinants of resistance to macrolides and tetracycline, and associated transposons, were detected by PCR and analysed by sequencing. GBS isolates represented 30 different sequence types (STs), grouped in four clonal complexes (CCs), and belonged to seven serotypes. Serotype III was predominant (36.0%), followed by Ia, V, Ib, II, IV and VI. The most common alp genes were rib (26.3%) and alp1/alp5 (23.7%). The bac gene encoding the beta-compound of the surface C-protein was present in 17.5% of isolates. Erythromycin resistance (18.4% of isolates) was found in all CCs, but was associated with serotype V and ST1. The most prevalent determinant of resistance was erm(B), usually located on the Tn3872-like transposon. Several changes were observed in the regulatory region of erm(B), some of them resulting in elevated ketolide MICs. Resistance to tetracycline was ubiquitous (91.2%) and its most common determinant was tet(M), occurring in several variants that were typically carried on Tn916-family transposons. Analysis of bacterial serotypes, alp genes and antimicrobial resistance determinants in the background of MLST-based population structure strengthened evidence of the importance of horizontal gene transfer in GBS evolution.

• Expansion and evolution of the Streptococcus pneumoniae Spain9V-ST156 clonal complex in Poland.

  Authors: Ewa Sadowy, Alicja Kuch, Marek Gniadkowski, Waleria Hryniewicz

  Antimicrobial agents and chemotherapy. 03/2010; 54(5):1720-7.

  In this study, we analyzed 118 penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) isolates (MICs, >or=0.12 microg/ml) recovered in Poland in 2003 to 2005 from patients with respiratory tractIn this study, we analyzed 118 penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) isolates (MICs, >or=0.12 microg/ml) recovered in Poland in 2003 to 2005 from patients with respiratory tract diseases and invasive infections. Seven different serotypes (14, 9V, 23F, 19F, 6B, 19A, and 6A, in order of descending frequency), seven alleles of the murM gene (murMA, murMB6, and the new murMB12 to -16 alleles), and 31 multilocus sequence types (STs) were observed. The vast majority of the PNSP isolates (90.7%) belonged to the international multiresistant clones, and among these, the Spain(9V)-ST156 clonal complex was the most prevalent (56 isolates) and was significantly overrepresented in invasive infections. The clone has been evolving rapidly, as demonstrated by the observed number of STs, the diversity in multiple-locus variable-number-tandem-repeat analysis (MLVA) types, and the polymorphism of pbp and pspA genes (coding for penicillin-binding proteins and the pneumococcal surface protein A, respectively). The presence and structure of the rlrA islet (encoding the pneumococcal pilus) were very well conserved. The Spain(9V)-ST156 clonal complex has been largely responsible for a decreasing susceptibility to penicillin among pneumococci in Poland in recent years, in spite of a relatively moderate antimicrobial use.

• Pyogenic streptococci--danger of re-emerging pathogens.

  Authors: Izabela Sitkiewicz, Waleria Hryniewicz

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2010; 59(4):219-26.

  Beta-hemolytic, pyogenic streptococci are classified according to type of major surface antigen into A (Streptococcus pyogenes), B (Streptococcus agalactiae), C (multiple species includingBeta-hemolytic, pyogenic streptococci are classified according to type of major surface antigen into A (Streptococcus pyogenes), B (Streptococcus agalactiae), C (multiple species including Streptococcus dysagalactiae) and G (multiple species including Streptococcus canis) Lancefield groups. Group A Streptococcus causes each year hundreds of thousands deaths globally as a result of infections and post-infectional sequelae. An increasing number of severe, invasive infections is caused by selected, specialized pathogenic clones. Within the last 50 years, an increasing number of human infections caused by groups B, C and G Streptococcus (GBS, GCS, GGS) has been observed worldwide. GBS was first identified as animal pathogen but the spectrum of diseases caused by GBS quickly shifted to human infections. Groups C and G Streptococcus are still regarded mostly as animal pathogens, however, an increased number of severe infections caused by these groups is observed. The increasing number of human infections caused worldwide by GCS/GGS can be a sign of similar development from animal to human pathogen as observed in case of GBS and this group will gain much more clinical interest in the future.The situation in Poland regarding invasive infections caused by pyogenic streptococci is underestimated.

• Antimicrobial susceptibility of metallo-beta-lactamase positive and negative Klebsiella pneumoniae strains isolated from intensive care unit patients.

  Authors: Alicja Sekowska, Waleria Hryniewicz, Marek Gniadkowski, Aleksander Deptuła, Krzysztof Kusza, Eugenia Gospodarek

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2010; 59(1):67-9.

  Carbapenem resistance in Gram-negative bacteria is a worldwide increasing and one of the most disturbing problems, given these antibiotics are drugs of choice in the treatment of infections caused byCarbapenem resistance in Gram-negative bacteria is a worldwide increasing and one of the most disturbing problems, given these antibiotics are drugs of choice in the treatment of infections caused by extended-spectrum-beta-lactamase producing strains. In this study the antibiotic susceptibility of metallo-beta-lactamase-positive and negative Klebsiella pneumoniae strains isolated from intensive care unit (ICU) patients was evaluated. The presence of genes encoding MBLs was determined with a commercial kit hyplex MBL ID (BAG HEALTH CARE). The MBL-producing isolates were the first K. pneumoniae isolates of this kind identified in Poland. It seems that methods for detecting MBLs in Enterobacteriaceae should be included in contemporary standards of microbiological diagnostics in the country.

• Complex nature of enterococcal pheromone-responsive plasmids.

  Authors: Ewa Wardal, Ewa Sadowy, Waleria Hryniewicz

  Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists. 01/2010; 59(2):79-87.

  Pheromone-responsive plasmids constitute a unique group of approximately 20 plasmids identified, as yet, only among enterococcal species. Several of their representatives, e.g. pAD1, pCF10, pPD1 andPheromone-responsive plasmids constitute a unique group of approximately 20 plasmids identified, as yet, only among enterococcal species. Several of their representatives, e.g. pAD1, pCF10, pPD1 and pAM373 have been extensively studied. These plasmids possess a sophisticated conjugation mechanism based on response to sex pheromones--small peptides produced by plasmid-free recipient cells. Detailed analysis of regulation and function of the pheromone response process revealed its great complexity and dual role--in plasmid conjugation and modulation of enterococcal virulence. Among other functional modules identified in pheromone plasmids, the stabilization/partition systems play a crucial role in stable maintenance of the plasmid molecule in host bacteria. Among them, the par locus of pAD1 is one of the exceptional RNA addiction systems. Pheromone-responsive plasmids contribute also to enterococcal phenotype being an important vehicle of antibiotic resistance in this genus. Both types of acquired vancomycin resistance determinants, vanA and vanB, as well many other resistant phenotypes, were found to be located on these plasmids. They also encode two basic agents of enterococcal virulence, i.e. aggregation substance (AS) and cytolysin. AS participates in mating-pair formation during conjugation but can also facilitate the adherence ofenterococci to human tissues during infection. The second protein, cytolysin, displays hemolytic activity and helps to invade eukaryotic cells. There are still many aspects of the nature of pheromone plasmids that remain unclear and more detailed studies are needed to understand their uniqueness and complexity.

• The effect of an antibiotic policy on the control of vancomycin-resistant enterococci outbreak and on the resistance patterns of bacteria isolated from the blood of patients in a hematology unit.

  Authors: Tomasz Ozorowski, Magdalena Kawalec, Maria Zaleska, Lech Konopka, Waleria Hryniewicz

  Polskie archiwum medycyny wewnetrznej. 11/2009; 119(11):712-718.

  INTRODUCTION: Antibiotic resistance has become one of the main medical problems worldwide. This is mainly due to an overuse and misuse of antibiotics. OBJECTIVES: The aim of the study was to assessINTRODUCTION: Antibiotic resistance has become one of the main medical problems worldwide. This is mainly due to an overuse and misuse of antibiotics. OBJECTIVES: The aim of the study was to assess the effect of an antibiotic policy and enhanced infection control on the occurrence of epidemic strains of vancomycin-resistant enterococci (VRE) and resistance patterns of bacteria isolated from the blood of patients hospitalized in two departments of a hematology center in Poland. PATIENTS AND METHODS: Antibiotic use was calculated in daily defined doses (DDD) per 100 patient-days during the two 5-month periods, before and after the introduction of the policy. Infection control measures included a 1-week screening for VRE rectal carriage and contact isolation. RESULTS: Antibiotic consumption decreased from 82.1 to 57.3 DDD per 100 patient-days, mainly because of a decrease in the use of co-trimoxazole, other antimicrobials active against anaerobes, and cephalosporins. A significant change in antibiotic resistance patterns was observed and in vitro efficacy of antibiotics against bacteria isolated from the blood increased remarkably. We managed to eradicate the outbreak of VRE. CONCLUSIONS: The introduction of antibiotic policy and enhanced infection control measures may prove efficacious in VRE control.

• International clones of Klebsiella pneumoniae and Escherichia coli with extended-spectrum {beta}-lactamases (ESBLs) in a Czech hospital.

  Authors: Jaroslav Hrabák, Joanna Empel, Tamara Bergerová, Karel Fajfrlík, Pavla Urbaskova, Izabela Kern-Zdanowicz, Waleria Hryniewicz, Marek Gniadkowski

  Journal of clinical microbiology. 09/2009;

  A 2-month survey of extended-spectrum beta-lactamase (ESBL) producers was performed in a Czech hospital. Klebsiella pneumoniae produced SHV-2, -5 or -12, Escherichia coli produced CTX-M-9 or -15, andA 2-month survey of extended-spectrum beta-lactamase (ESBL) producers was performed in a Czech hospital. Klebsiella pneumoniae produced SHV-2, -5 or -12, Escherichia coli produced CTX-M-9 or -15, and other species produced TEM-92 or -132. All K. pneumoniae and E. coli isolates belonged to world-wide-spread sequence types, STs, or clonal complexes, CCs, (K. pneumoniae CC11, CC14 and ST101, and E. coli CC31, CC73, CC131 and CC405), and carried various plasmids (mainly with A/C- and FII-type replicons).