E. Petinaki

Anti–saccharomyces cerevisiae mannan antibodies and antineutrophil cytoplasmic autoantibodies in Greek patients with inflammatory bowel disease

OBJECTIVES:The combined measurement of perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) and anti–Saccharomyces cerevisiae mannan antibodies (ASCA) has recently been suggested as a valuable diagnostic approach in inflammatory bowel disease (IBD). The aim of this study was to assess the value of detecting pANCA and ASCA in the differentiation between ulcerative colitis (UC) and Crohns disease (CD) in a Greek population with IBD.METHODS:Sera were collected from 157 patients with IBD (97 with UC, 56 with CD, and four with indeterminate colitis) and 150 healthy controls. Determination of pANCA was performed by a standard indirect immunofluorescence technique on ethanol-fixed granulocytes and ASCA by an ELISA assay.RESULTS:In patients with UC, sensitivity, specificity, positive predictive value, and negative predictive value of the pANCA test was 67%, 84%, 93%, and 46% respectively. These values did not change significantly when the combination of positive pANCA and negative ASCA was used. ASCA test in diagnosing CD yielded a sensitivity, specificity, positive predictive value, and negative predictive value of 39%, 89%, 54%, and 81%. The combination of pANCA negative and ASCA positive increased the positive predictive value to 77% and it was associated with small bowel disease.CONCLUSIONS:A positive pANCA test in Greek patients has a diagnostic value in confirming a diagnosis of UC. Measurement of pANCA and ASCA together has a rather limited value in the differential diagnosis between UC and CD but may be of help in studying disease heterogeneity.

Emergence of Escherichia coli sequence type 410 (ST410) with KPC-2 β-lactamase

Fifteen carbapenem-non-susceptible Escherichia coli isolates obtained during the period May 2010 to April 2011 in a hospital and a long-term care facility (LTCF) in Larissa (Central Greece) were investigated. Minimum inhibitory concentrations (MICs) to various antimicrobial agents were determined by Etest. Carriage of bla genes, including bla(KPC-2) and bla(CTX-M), was documented by polymerase chain reaction (PCR) and sequencing. Production of β-lactamases was confirmed by isoelectric focusing. Transfer of resistance was carried out by conjugation. Plasmid incompatibility groups were determined by PCR-based replicon typing and replicon sequence typing. Isolates were genotyped by multilocus sequence typing. Ten E. coli isolates with KPC-2 were derived from seven patients in the University Hospital of Larissa. Six patients had previously been treated for prolonged time periods in a LTCF located in the same city. The remaining isolate was from a patient previously treated in an Athens hospital. Screening of faecal samples from 20 randomly selected LTCF patients yielded eight enterobacteria with KPC-2, of which five were E. coli, showing the wide spread of KPC-2-producers in this institution and confirming that it was the focus of the outbreak. Fourteen of the isolates were classified as sequence type 410 (ST410); the remaining isolate belonged to a novel ST (ST2281). All 15 isolates carried a KPC-2-encoding plasmid of the Inc group FIIK. Additional plasmids encoding enzymes of the CTX-M-1 family were identified in 11 isolates. The bla(KPC-2)-carrying plasmid IncFIIK, widespread amongst Klebsiella pneumoniae in Greece, has probably been acquired by E. coli ST410 known to be associated with CTX-M production. Diffusion of bla(KPC-2) in common pathogens such as E. coli is of concern.

Survey of methicillin-resistant coagulase-negative staphylococci in the hospitals of central Greece

A sample of 450 consecutive, non-replicated coagulase-negative staphylococci (CoNS), collected from clinical specimens during the period 2000-2001 from the five major hospitals of Thessaly district (Central Greece) were investigated for resistance to methicillin. Most of the isolates had been collected in a sporadic fashion from the intensive care units and the surgical wards of the participating hospitals. The majority of the isolates (76%) were Staphylococcus epidermidis (50%), Staphylococcus haemolyticus (14.8%) and Staphylococcus hominis (11.1%). All 316 isolates (70%) were classified as resistant according to NCCLS breakpoints (MIC > or =0.5 mg/l); 268 (59.5%) of them were mecA-positive in a PCR-based assay. All isolates with MIC > or =8 mg/l carried the gene, while, only 23.8% of isolates with MIC, 0.5-4 mg/l were carriers. Only 9% of the mecA-positive isolates were found to be sensitive to various non-beta-lactams, while 41.8% of the isolates were resistant to more than three antimicrobial groups apart from beta-lactams. Molecular typing by PFGE showed apparent heterogeneity among isolates of each species and the absence of predominant clones.

Methicillin-resistant Staphylococcus aureus among companion and food-chain animals: impact of human contacts

Methicillin-resistant Staphylococcus aureus (MRSA), one of the major pathogens in humans, is a cause of infection and colonization among animals. The increasing number of companion animals and antibiotic use have made this population a reservoir of MRSA. In parallel, the evolution of new MRSA clones and mec homologues among animals of the food chain has emphasized the need for infection control practices in animals and humans in close contact. On the basis of a review of the literature, epidemiological and evolutionary data for MRSA infections and carriage, risk factors and control strategies are presented.

Comparative Evaluation of Three Commercial Identification Systems Using Common and Rare Bloodstream Yeast Isolates

ABSTRACT The commercial yeast identification systems API ID32C, Auxacolor, and Vitek were evaluated using 251 molecularly identified bloodstream isolates and 2 reference strains, representing a total of 35 species (6 common and 29 rare). Correct identification rates were higher for common species (Auxacolor, 95%; API ID32C, 94%; Vitek, 92%) than for rare species (Auxacolor, 43%; API ID32C, 56%; Vitek, 64%). All systems performed equally among the former, and Vitek performed best among the latter.

Direct Detection of Cardiobacterium hominis in Serum from a Patient with Infective Endocarditis by Broad-Range Bacterial PCR

ABSTRACT Bacterial DNA was detected directly in the serum of a patient with endocarditis by broad-range 16S rRNA PCR followed by sequencing and analysis of the results by the BLAST search. Using these methods, Cardiobacterium hominis was identified in 2 days from the date of serum collection. The microorganism was also isolated and identified using conventional methods (bacterial culture and biochemical tests) 17 days from the date of sample collection. This is the first report showing the direct detection of C. hominis in a patients serum using molecular-based methods, emphasizing their potential usefulness as additional and rapid diagnostic tools for the detection and identification of fastidious bacteria.

Carbapenemase-producing Pseudomonas aeruginosa from central Greece : molecular epidemiology and genetic analysis of class I integrons

BackgroundMultidrug-resistant Pseudomonas aeruginosa is a serious challenge for antimicrobial therapy of nosocomial infections, as it possesses several mechanisms of antimicrobial resistance. In Central Greece, a sudden increase of infections caused by carbapenem-resistant P. aeruginosa was observed during 2011, indicating the need for further analysis.MethodsFive-hundred and sixty-eight P. aeruginosa isolates were collected consecutively during an 8-month period in 2011 from inpatients treated in three hospitals in the Thessaly region (1,000,000 habitants) of Greece. Carbapenem-resistant P. aeruginosa (n = 284) were characterized by antimicrobial susceptibility testing and β-lactamase content, and the genetic relatedness of carbapenemase-producing isolates was assessed by BOX-PCR, multilocus sequence typing, and eBURST analysis. Mapping of the class I integrons of Verona integron-encoded metallo-β-lactamase (VIM)-carrying isolates was also performed, and clinical data of the VIM producers were reviewed.ResultsEighty (14.1%) out of the 568 P. aeruginosa isolates recovered from clinical specimens were VIM producers. Multilocus sequence typing revealed high prevalence of the international clones ST111 and ST235 among blaVIM-2- and blaVIM-4-positive isolates, respectively. blaVIM-17 was identified in an isolate of a novel sequence type (ST1457). blaVIM gene cassettes were carried by five distinct class I integrons, including two novel ones.ConclusionsSince the first report of VIM-producing P. aeruginosa in 2000, this microorganism still remains among the most prevalent multidrug resistant pathogens in Greece. The spread of VIM-producers belonging to the most common international clones (ST111 and ST235), the spread of integrons of divergent structures, and the emergence of novel integrons underscore their ongoing evolution.

Dissemination of two international linezolid-resistant Staphylococcus epidermidis clones in Greek hospitals

mutations, multilocus sequence typing, Greece,staphylococciSir,The growing number of infections caused by multidrug-resistantStaphylococcus epidermidis has necessitated the use of newantimicrobials, such as linezolid, and enhanced the emergenceof linezolid-resistant S. epidermidis strains. To date, mutations ofregion V of 23S rRNA (G2447T, T2504A, C2534T, G2576T,G2603T and G2631T) have been associated with the expressionof linezolid resistance among clinical staphylococcal isolates.

Characterization of Metallo-β-Lactamase VIM-27, an A57S Mutant of VIM-1 Associated with Klebsiella pneumoniae ST147

ABSTRACT VIM-27 metallo-β-lactamase, an Ala57 → Ser variant of VIM-1, was identified in three Klebsiella pneumoniae isolates belonging to sequence type 147. blaVIM-27 was part of a class 1 integron carried by non-self-transferable plasmids. Kinetic parameters and MIC determinations indicated that VIM-27 hydrolyzed most β-lactams, especially imipenem and cefoxitin, less effectively than VIM-1.

Evaluation of a novel method based on PCR Restriction Fragment Length Polymorphism Analysis of the tuf gene for the identification of Staphylococcus species.

A novel method, based on PCR Restriction Fragment Length Polymorphism Analysis (PRA) of a part of the tuf gene (370 bp), was designed for the identification of 11 staphylococcal species, including the most common staphylococcal pathogens. A total of 258 clinical isolates were validated by this assay, and the results were in concordance with those obtained by the reference method of Kloos and Schleifer.