Characterization of Extensively Drug-Resistant or Pandrug-Resistant Sequence Type 147 and 101 OXA-48-Producing Klebsiella pneumoniae Causing Bloodstream Infections in Patients in an Intensive Care Unit.

Carbapenem-resistant causes important health care-associated infections worldwide. An outbreak of sequence type 11 (ST11) OXA-48-producing (OXA-48-Kp) isolates occurred in Tzaneio Hospital in 2012 and was contained until 2014, when OXA-48-Kp reemerged. The present study involved 19 bloodstream infection (BSI) OXA-48-Kp isolates recovered from 19 intensive care unit (ICU) patients hospitalized between August 2014 and July 2016.

Performance of the β LACTA™ test for rapid detection of expanded-spectrum cephalosporin-non-susceptible Enterobacteriaceae.

Objectives: The aim of this study was to examine the performance of the chromogenic β LACTA™ test for the rapid detection of expanded-spectrum cephalosporin (ESC) non-susceptibility among Enterobacteriaceae in a region endemic for potent β-lactamases.

Methods: The β LACTA™ test was applied prospectively on 235 consecutive Enterobacteriaceae clinical isolates and 163 previously characterised ESC-non-susceptible Enterobacteriaceae producing a range of β-lactamases.

Results: The β LACTA™ test exhibited excellent sensitivity (96.

Wide dissemination of linezolid-resistant Staphylococcus epidermidis in Greece is associated with a linezolid-dependent ST22 clone.

Objectives: Dependence on linezolid was recently described as significant growth acceleration of linezolid-resistant Staphylococcus epidermidis (LRSE) isolates upon linezolid exposure. We investigated the possible contribution of linezolid dependence to LRSE dissemination in Greece.

Methods: Linezolid resistance rates were estimated in six tertiary hospitals located throughout Greece between 2011 and 2013.

Isolated microorganisms in plastic biliary stents placed for benign and malignant diseases.

Background: Biliary stenting is a well-established method to treat patients with malignant and benign biliary diseases. However, occlusion of plastic biliary stents is considered as a drawback and bacterial colonization seems to be the key factor in this process.

Methods: During a 3-year period, 51 plastic biliary stents were extracted from 42 patients.

A combined disk test for direct differentiation of carbapenemase-producing enterobacteriaceae in surveillance rectal swabs.

Carbapenemase-producing Enterobacteriaceae (CPE) are rapidly spreading worldwide. Early detection of fecal CPE carriers is essential for effective infection control. Here, we evaluated the performance of a meropenem combined disk test (CDT) for rapidly differentiating CPE isolates directly from rectal swabs.

Linezolid dependence in Staphylococcus epidermidis bloodstream isolates.

We document linezolid dependence among 5 highly linezolid-resistant (LRSE) Staphylococcus epidermidis bloodstream isolates that grew substantially faster at 32 µg/mL linezolid presence. These isolates carried the mutations T2504A and C2534T in multiple 23S rRNA copies and 2 mutations leading to relevant amino acid substitutions in L3 protein. Linezolid dependence could account for increasing LRSE emergence.

Outbreak of OXA-48 carbapenemase-producing Klebsiella pneumoniae in Greece involving an ST11 clone.

Objectives: First detected in Enterobacteriaceae isolates in Turkey, the OXA-48 carbapenemase has gradually disseminated in the wider Mediterranean area and Europe. Despite reports from other European regions, until now no such isolates have been detected in Greece. We describe the characteristics of the first outbreak caused by OXA-48-producing Klebsiella pneumoniae in Greece.

Comparative evaluation of tigecycline susceptibility testing methods for expanded-spectrum cephalosporin- and carbapenem-resistant gram-negative pathogens.

We evaluated the Vitek2, Etest, and MIC Test Strip (MTS) methods of tigecycline susceptibility testing with 241 expanded-spectrum cephalosporin-resistant and/or carbapenem-resistant Enterobacteriaceae and Acinetobacter baumannii clinical isolates by using dry-form broth microdilution (BMD) as the reference method. The MIC(50/90)s were as follows: BMD, 1/4 μg/ml; Vitek2, 4/≥8 μg/ml; Etest, 2/4 μg/ml; MTS, 0.5/2 μg/ml.

Comparative evaluation of combined-disk tests using different boronic acid compounds for detection of klebsiella pneumoniae carbapenemase-producing enterobacteriaceae clinical isolates.

The accurate phenotypic detection of Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae is an increasing necessity worldwide. We evaluated the performance of boronic acid combined-disk tests using as substrate imipenem or meropenem and as inhibitor of KPC production 300 μg aminophenylboronic acid (APBA), 600 μg APBA, or 400 μg phenylboronic acid (PBA). Tests were considered positive when an increase in the growth-inhibitory zone around a carbapenem disk with KPC inhibitor was 5 mm or greater of the growth-inhibitory zone diameter around the disk containing carbapenem alone.

A simple phenotypic method for the differentiation of metallo-beta-lactamases and class A KPC carbapenemases in Enterobacteriaceae clinical isolates.

Background: The increasing frequency of class A KPC enzymes and class B metallo-beta-lactamases (MBLs) among Enterobacteriaceae as well as their possible co-production makes their early differentiation urgent.

Methods: A simple phenotypic algorithm employing three combined-disc tests consisting of meropenem alone and with phenylboronic acid (PBA), EDTA, or both PBA and EDTA was designed for the differentiation of KPC and MBL enzymes. Augmentation of the zone of inhibition by >or=5 mm was considered a positive combined-disc test result.

Risk factors and outcomes associated with acquisition of colistin-resistant KPC-producing Klebsiella pneumoniae: a matched case-control study.

A matched 1:3 case-control study investigated factors predicting colistin-resistant versus colistin-susceptible KPC-producing Klebsiella pneumoniae acquisition and its impact on patient outcomes. Case patients were more often admitted from other institutions (P = 0.019) and had longer therapy with beta-lactam/beta-lactamase inhibitors (P = 0.

Use of boronic acid disk tests to detect extended- spectrum beta-lactamases in clinical isolates of KPC carbapenemase-possessing enterobacteriaceae.

We evaluated boronic acid (BA)-based methods for their ability to detect extended-spectrum beta-lactamases (ESBLs) among clinical isolates of KPC-producing members of the Enterobacteriaceae family. A total of 155 isolates of Klebsiella pneumoniae (n = 141), Escherichia coli (n = 6), Enterobacter aerogenes (n = 6), and Klebsiella oxytoca (n = 2) genotypically confirmed to be KPC producers were analyzed. As many as 118 isolates harbored ESBLs (103 harbored SHV-type ESBLs, 13 harbored CTX-M-type ESBLs, and 2 harbored both SHV- and CTX-M-type ESBLs); the remaining 37 isolates were genotypically negative for ESBL production.

Evaluation of boronic acid disk tests for differentiating KPC-possessing Klebsiella pneumoniae isolates in the clinical laboratory.

The worldwide increase in the occurrence and dissemination of KPC beta-lactamases among gram-negative pathogens makes critical the early detection of these enzymes. Boronic acid disk tests using different antibiotic substrates were evaluated for detection of KPC-possessing Klebsiella pneumoniae isolates. A total of 57 genotypically confirmed KPC-possessing K.