24 research outputs found
Determination of clinical significance of coagulase-negative staphylococci in blood cultures
The aim of this study was to investigate the criteria used to distinguish coagulase-negative staphylococci (CoNS) bacteremia from contamination. We evaluated 162 adult patients with CoNS-positive blood cultures (BCs). Of the 162 patients, 35 (21.6%) had at least 2 positive BCs and 127 (78.4%) had a single positive BC. According to the Laboratory-Confirmed Bloodstream Infection (LCBI) criteria, 24 (14.8%) patients with the same species of CoNS had true bacteremia, and 138 (85.2%) patients had contaminants. Despite the detection of the same CoNS species, 9 of the 24 patients had different CoNS genotypes. Using clinical assessments, only 20 patients were diagnosed with true bacteremia, 8 of them had a single positive BC. We concluded that only using the LCBI criteria or clinical evaluations of a patient were not sufficient to distinguish CoNS bacteremia from contamination. Molecular identification should also be performed as a diagnostic laboratory parameter for CoNS bacteremia. (C) 2016 Elsevier Inc. All rights reserved
Investigation of carbapenem resistance and the first identification of Klebsiella pneumoniae carbapenemase (KPC) enzyme among Escherichia coli isolates in Turkey: A prospective study
Background: The aim of this study was to determine the presence of carbapenem resistance and carbapenemase production in Escherichia coil isolates from clinical samples in Turkey
Development of a Rapid Molecular Test Format Based on Isothermal Recombinase Polymerase Amplification Technique and Lateral Flow Method for Detection of bla(OXA-48)
Objective: Molecular tests are rapid, reliable tools for the detection of carbapenem resistance, but their use is limited due to their cost, requirement for well-trained technicians and highly sophisticated instrumentation. The recombinase polymerase amplification (RPA) assay, one of the isothermal amplification methods developed recently to overcome these problems, doesn't require denaturation of target, and RPA products can be determined by probe-base detection methods even without a specific instrumentation. In this study, we aimed to develop a rapid and easily applicable molecular test format in on-site settings based on RPA technique with combination of lateral flow system for detection of bla(OXA-48)
The Epidemiological and Molecular Characterization of Vancomycin-Resistant Enterococci Isolated from Rectal Swab Samples of Hospitalized Patients in Turkey
Background: Vancomycin-resistant enterococci (VRE) are a serious problem all over the world. The present study was conducted to investigate antimicrobial resistance patterns, genotypes, clonal relationship, and virulence factors of VRE species isolated from rectal swab samples of hospitalized patients, patient's relatives, and medical staff at Istanbul University Cerrahpasa Medical School hospital
Microorganisms in Respiratory Tract of Patients Diagnosed with Atypical Pneumonia: Results of a Research Based on the Use of Reverse Transcription Polymerase Chain Reaction (RT-PCR) DNA Microarray Method and Enzyme-Linked Immunosorbent Assay
Background: Numerous molecular-based tests were applied for the laboratory-based diagnosis of viruses. In this cross-sectional case control study, in addition to bacteria, we aimed to determine respiratory viruses using, for the first time in our country, the Reverse Transcription PCR DNA Microarray method, and we also aimed to evaluate its diagnostic performance
Genotypes of hepatitis a virus in Turkey: first report and clinical profile of children infected with sub-genotypes IA and IIIA
Abstract Background Hepatitis A virus (HAV) is a food and water-borne virus causing clinical (mainly hepatitis) and subclinical disease in humans. It is important to characterize circulating strains of HAV in order to prevent HAV infections using efficacious vaccines. The aim of this study was the detection and characterization of the circulating strains of HAV in Turkey by performing serology, RT-PCR, sequencing and phylogenetic analysis. Methods In this study, 355 HAV suspected cases were analysed by ELISA for the presence of antibodies to HAV. RNA was extracted from 54 HAV IgM positive human sera. None of the suspect cases were vaccinated against HAV and they never received blood transfusions. Samples found positive by RT-PCR using primers targeting the VP1/VP2A junction and VP1/VP3 capsid region of HAV, were subjected to sequencing and phylogenetic analyses. Results IgM type antibodies to HAV were detected in 54 patients. Twenty one of them were students. The age of IgM positive cases was between 3 and 60 years. IgM positivity differed in age groups and was higher in the age group 3 to 10 years. Phylogenetic analysis showed that the majority of HAV strains detected in this study belong to the “HAV 1B” cluster. In addition, the HAV sub-genotypes IA (KT874461.1) and IIIA (KT222963.1) were found in 2 children. These sub-genotypes were not previously reported in Turkey. The child who carried sub-genotype IIIA travelled to Afghanistan and presented with abdominal pain, icterus and vomitus. He was positive for anti-HAV IgM and IgG but negative for hepatitis B and C. Liver enzymes like aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transferase and lactate dehydrogenase were severely elevated. Bilirubin levels were also increased. White blood cells, neutrophils and hemoglobin were decreased while lymphocytes and monocytes were increased. Similar clinical signs and laboratory findings were reported for the child infected with sub-genotype IA but aspartate aminotransferase and alanine aminotransferase were not severely elevated. Conclusions The results indicate that molecular studies determining the HAV genotype variation in Turkey are timely and warranted. The majority of IgM positive cases in 3–10 year old patients indicate that childhood vaccination is important. Sub-genotype IB is the most prevalant genotype in Turkey. Surprisingly, sub-genotype IA and IIIA are also present in Turkey; future diagnostic efforts need to include diagnostic methods which can identify this emerging HAV genotypes. Our results also show that one important risk factor for contracting hepatitis A virus is international travel since genotype IIIA was detected in a child who had travelled to Afghanistan
Genotypes of hepatitis a virus in Turkey: first report and clinical profile of children infected with sub-genotypes IA and IIIA
Background: Hepatitis A virus (HAV) is a food and water-borne virus causing clinical (mainly hepatitis) and subclinical disease in humans. It is important to characterize circulating strains of HAV in order to prevent HAV infections using efficacious vaccines. The aim of this study was the detection and characterization of the circulating strains of HAV in Turkey by performing serology, RT-PCR, sequencing and phylogenetic analysis