Kirca Yilmaz, Ş. | Acuner, I.Ç. | Strommenger, B. | Bek, Y. | Witte, W.

Article | 2014 | Mikrobiyoloji Bulteni48 ( 1 ) , pp.14 - 27

The increase in the prevalence of epidemic strains of methicillin resistant Staphylococcus aureus (MRSA) in hospitals and community requires special attention of infection control. The aim of this study was to determine the pathogenic phenotype (i.e. infectivity and resistotype) and genotypic character-istics (i.e. PFGE-pulsotyping, SLST-spa typing, MLST-sequence typing, eBURST-clonal complex detection algorithm) of clinical MRSA isolates in the Central Blacksea region of Turkey, in order to understand their short- and long-term epidemiological and evolutionary dynamics, and to investigate any probable presence of a significant clus . . .tering. This prospective study included consecutive but non-repetitive 48 MRSA isolates (of them 18 were colonized strains and 30 were causes of nosocomial infection) and seven methicillin-susceptible S.aureus (MSSA, all were isolated from nosocomial infection), collected between December 2006-February 2007 period from hospitalized patients. Identification of the isolates were performed by Vitek-2 automated system (BioMérieux, USA), and in vitro antimicrobial susceptibility testing by broth microdilution method and Vitek-2 automated system. The MRSA isolates found susceptible to erythromycin (n= 10) were further investigated for the presence of ermA gene by the PCR method. All the strains were typed by spa-typing and PFGE-pulsotyping methods. Among the isolates with different spa-types, representatives were selected (3 MRSA, 7 MSSA) and typed with MLST typing method. Among the isolates with different spa-types, representatives with different antimicrobial susceptibility patterns were selected (n= 8), and SCCmec types were determined by the multiplex PCR method. Antimicrobial resistance patterns of the isolates were digitized to get standardized antimicrobial resistance phenotypes. Clustering of MRSA isolates in pattern groups on the basis of discriminatory characteristics, namely infectivity, phenotype and genotype were statistically analyzed with specific inclusion and exclusion criteria. As a result, three different antimicrobial resistance phenotypes were found in MSSA isolates, whereas 13 were identified in MRSA isolates. In MSSA isolates, seven different PFGE-pulsotypes were detected, as compared to 14 pulsotypes in MRSA isolates. Among MRSA isolates, 10 sporadic strains with single PFGE-pulsotypes were detected. All MRSA isolates, with two exceptions (t459, t632), were of t030 spa-type; in the MLST analysis of the representatives of different spa-types (n= 3), a single type of MLST-clonal complex (CC8) and single MLST-sequence type (ST239) were identified. Each of the seven MSSA isolates yielded different spa-types, MLST-clonal complex types and MLST-sequence types (t777-ST5-CC5; t660-ST25-CC5; t153-ST34-CC30; t015-ST45-CC45; t267-ST97-CC97; t377-ST360-CC8; t084-ST15-C15). In the statistical analysis of 38 non-sporadic MRSA isolates, the isolates in Group-13 (n= 16; infectious, resistotype 14, pulsotype 4; antimicrobial resistance score= 24) displayed significant infectivity-phenotype-genotype clustering (p< 0.001). In 27 of the MRSA isolates, decreased susceptibility to teicoplanin (MIC= 4 µg/mL) was detected. Although, global MRSA isolates belonging to MLST-CC8, MLST-ST239, t030 spa-type were usually expected to be resistant to erythromycin, 10 such strains were erythromycin susceptible. However, ermA gene was found in six of these 10 strains, leading to a conclusion that the ermA gene of these isolates might be dysfunctional due to a point mutation or deletion. Selected representatives of MRSA isolates with different antimicrobial susceptibility patterns (n= 8) were detected to be SCCmec type III. In conclusion, S.aureus isolates in the patient population of our hospital representing the Central Blacksea region showed statistically significant clustering in infectivity, antimicrobial resistance phenotype and clonal genotype (p< 0.001). The dominant MRSA clone was ST239 which was one of the five major pandemic MRSA clones. Nosocomial MSSA isolates displayed long-term clonal diversity. This study produced regional evolutionary-epidemiological data that may support further regional, national and international long-term surveillance studies of S.aureus strains Daha fazlası Daha az

Midilli, K. | Yilmaz, G. | Türkoglu, S. | Iskanova, B. | Ergin, S. | Yarimcam, F. | Altaş, K.

Article | 2010 | Mikrobiyoloji Bulteni44 ( 3 ) , pp.405 - 413

Human bocavirus (HBoV) which was described in 2005 by molecular techniques, is a member of Parvoviridae. The role of HBoV is being questioned in acute respiratory diseases (ARD) in many recent studies. The aim of this study was to determine the presence of HBoV DNA in the respiratory specimens of patients with ARD. A total of 155 throat swab and/or washing specimens from 76 children and 79 adults with ARD were examined. HBoV DNA was investigated by single step in-house polymerase chain reaction (PCR) using NS1 primers (5- 'TATGGCCAAGGCAATCGTCCAAG-3', 5'-GCC GCGTGAACATGAGAAA-CAG-3') which amplify the 290 base pair region of NS1 gene . . .located between nucleotides 1545-1835 of prototype HBoV st1 strain. HBoV DNA was detected in 5 (6.5%) of 76 children and 2 (2.5%) of 79 adults. Three sequenced samples showed 100% homology with the reference sequences. This study in which HBoV DNA was detected in children and adults with ARD, is the first HBoV prevalence study in Turkey. Larger scale prospective clinical and molecular studies are required to explain the association between HBoV and respiratory disease Daha fazlası Daha az