External quality control survey on identification of microorganisms using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（ MALDI-TOF MS） is a bacterial typing tool that was approved as a medical device in 2011. However, external accuracy control examination of bacterial typing using mass spectrometry is still only performed on a small scale. In this study, E.

Characteristics of pediatric patients claimed with acute upper respiratory infection during otorhinolaryngology consultations: A descriptive study of a large Japanese medical claims database.

This study aimed to clarify other diseases claimed simultaneously with acute upper respiratory infection (URI), antibiotic prescriptions, and examinations associated with infectious diseases in pediatric patients with acute URI insurance claims at otorhinolaryngology outpatient visits. Pediatric patients who visited an otolaryngology department between 2019 and 2021 and were definitively diagnosed with URI were selected using a large Japanese medical claims database. Patient backgrounds, antibiotic use, and examinations were descriptively evaluated.

Verification of quality assurance for blood culture surveillance using 6 years of data from the Japan Infection Prevention and Control Conference for National and Public University Hospitals.

The importance of blood culture has been widely recognized, and there is a need for monitoring to evaluate the accuracy of blood culture that reflects domestic healthcare systems. In this study, we assessed 6-year trends in blood culture quality assurance data. The Japan Infection Prevention and Control Conference for National and Public University Hospitals conducted yearly blood culture surveillance at 52 national public university hospitals from 2015 to 2020.

Examination of Conditions for External Quality Control in Identification of Microorganisms using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was approved for medical use in 2011 and is currently used as a rapid, accurate and lowcost technique for bacterial identification. External quality control for medical analysis is monitored using tests of the Japanese Association of Medical Technologists and Prefectural Association of Clinical Laboratory Technologists and through user surveys of reagent and equipment manufacturers. However, external quality control of bacterial typing using MS is not performed.

Genetic and epidemiological analysis of ESBL-producing Klebsiella pneumoniae in three Japanese university hospitals.

Introduction: We aimed to clarify the genetic background and molecular epidemiology of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae (K. pneumoniae) at three geographically separated university hospitals in Japan.

Methods: From January 2014 to December 2016, 118 ESBL-producing K.

Stepwise Evolution of a Klebsiella pneumoniae Clone within a Host Leading to Increased Multidrug Resistance.

Five -positive Klebsiella pneumoniae isolates (KpWEA1, KpWEA2, KpWEA3, KpWEA4-1, and KpWEA4-2) were consecutively obtained from a patient with relapsed acute myeloid leukemia who was continuously administered antimicrobials. Compared with KpWEA1 and KpWEA2, KpWEA3 showed decreased susceptibility to antimicrobials, and KpWEA4-1 and KpWEA4-2 (isolated from a single specimen) showed further-elevated multidrug-resistance (MDR) phenotypes. This study aims to clarify the clonality of the five isolates and their evolutionary processes leading to MDR by comparison of these complete genomes.

Examination of conditions for regular internal quality control in identification of microorganisms using MALDI-TOF MS.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was approved for medical use in 2011, and is currently used as a rapid, accurate and low-cost technique for bacterial identification. Microbiological testing and internal accuracy control in Japan are mainly implemented in accordance with the standards of the Clinical and Laboratory Standards Institute (CLSI). However, few facilities perform internal accuracy control of bacterial identification by MALDI-TOF MS.

Within-host evolution of a Klebsiella pneumoniae clone: selected mutations associated with the alteration of outer membrane protein expression conferred multidrug resistance.

Background: A patient repeatedly developed bacteraemia despite the continuous use of antibiotics. We obtained two Klebsiella pneumoniae isolates from the patient's blood on Days 72 and 105 after hospitalization. Each of the two isolates belonged to ST45, but while the first isolate was susceptible to most antibiotics, the second one was resistant to multiple drugs including carbapenems.

Clinical and pathogenic features of SCCmec type II and IV methicillin-resistant Staphylococcus aureus in Japan.

Staphylococcal chromosomal cassette mec (SCCmec) type IV methicillin-resistant Staphylococcus aureus (MRSA) has rapidly disseminated in healthcare settings, and its characteristics in the United States and Europe are well known. Because Japanese SCCmec type IV MRSA clones are different and less well documented, this retrospective, single center study was done to determine and compare the characteristics of SCCmec type II and IV MRSA in Japan. For the analysis, 55 SCCmec type II and 101 type IV MRSA samples were collected from lower respiratory tract specimens or from skin or soft tissue.

A dramatic increase in the positive blood culture rates of Helicobacter cinaedi: the evidence of differential detection abilities between the Bactec and BacT/Alert systems.

In our hospital, positive blood culture rates of Helicobacter cinaedi dramatically increased after introducing the Bactec system. A simulated culture model of H. cinaedi bacteremia demonstrated no positive signals using the BacT/Alert system, despite efficient growth in bottles.

Comparison of two types of matrix-assisted laser desorption/ionization time-of-flight mass spectrometer for the identification and typing of Clostridium difficile.

Microflex LT (Bruker Daltonics) and VITEK MS (bioMérieux) are bacterial identification systems that are based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). For VITEK MS, two identification softwares, VITEK MS IVD (IVD) and SARAMIS (SARAMIS), are available. Microflex LT is equipped with MALDI Biotyper RTC software (Biotyper).

[Surveillance report of drug-resistant bacteria from 2007 to 2012 in Saga Prefecture, Japan (the second report)].

Drug-resistant bacteria are a problematic issue in Japan. Surveillance of drug-resistant bacteria is important because the frequency of isolation and kinds of such bacteria vary between hospitals and local areas. This study summarizes the results of detection of drug-resistant bacteria in Saga Prefecture from July 2007 to June 2012.

Successful treatment of invasive zygomycosis based on a prompt diagnosis using molecular methods in a patient with acute myelogenous leukemia.

Zygomycosis is a lethal and invasive mold infection that is often associated with hematological malignancies. The keys for successful treatment include making a rapid diagnosis and appropriately administering antifungal agents. We herein report the early diagnosis of a case of zygomycosis in a patient with acute myeloid leukemia using a deoxyribonucleic acid sequence analysis.

[Distributions and spreads of antimicrobial drug-resistant microorganisms in Saga prefecture].

We investigated the distribution of drug-resistant organisms to clarify transmission of the organisms. Drug-resistant organisms were surveyed in 12 facilities in 4 districts of Saga prefecture for 2 years, and were analyzed by beta-lactamase typing, antimicrobial susceptibility tests and pulsed-field gel electrophoresis (PFGE). The number of isolates was 111,505 for the 2 years.

[Microbiological and clinical features of nine cases with nocardial infections].

Following recent advance in medical technology, the increase of immunocompromised patients results in an increase of opportunistic infections such as nocardiosis. However, little is known about relationships between clinical features of nocardial infections and each Nocardia species, especially newly identified ones. Therefore, we identified clinical isolates of Nocardia species by genetic methods and analyzed clinical features of nocardiosis.

[Comparison of the antimicrobial susceptibility testing with three automated systems for MRSA, VISA, ESBL-producing Escherichia coli and Klebsiella pneumoniae].

Some automated systems of the identification and susceptibility for microorganisms are used and prevail in hospital laboratories. One of the most serious problems is to perform accurate susceptibility testing for low-level resistant organisms, while antibiotic resistant microbes are increasing in medical fields. To evaluate automated machines for the susceptibility testing, several antibiotic resistant organisms were examined by plural technicians in some laboratories.

Clonal spread in Eastern Asia of ciprofloxacin-resistant Escherichia coli serogroup O25 strains, and associated virulence factors.

A significant problem in the field of infectious diseases is the increase in fluoroquinolone (FQ)-resistant Escherichia coli. Although mutation of strains and clonal dissemination are supposed to be the cause of this increase, little is known about the prevalence of this organism. We investigated 219 FQ-resistant E.

Geographic distribution of fluoroquinolone-resistant Escherichia coli strains in Asia.

Fluoroquinolone (FQ) resistance is usually caused by point mutations within the quinolone resistance-determining regions (QRDRs) of gyrA, gyrB, parC and/or parE. However, little is known about the worldwide increase in FQ-resistant Escherichia coli or, more specifically, about the geographical distribution of QRDR mutations and the clonal spread of isolates. In this study, we analysed 68 FQ-resistant E.

Survey of human immunodeficiency virus (HIV)-seropositive patients with mycobacterial infection in Japan.

Objective: To assess DNA polymorphisms in mycobacterial isolates obtained from human immunodeficiency virus (HIV)-seropositive patients with tuberculosis in Japan from 1996 to 2003.

Methods: Restriction fragment length polymorphisms (RFLP) from Mycobacterium tuberculosis and Mycobacterium avium isolates obtained from individual seropositive patients with tuberculosis (n=78) were analysed with the use of IS6110 and (CGG)(5) or IS1245 and IS1311, respectively, as markers. As a control, the same procedures were applied to isolates from HIV-seronegative tuberculosis patients (n=87).

[Molecular epidemiologic analysis of nosocomocal infection due to TEIC resistant MRSA strains].

We performed epidemiologic study of 109 strains of methicillin resistant Staphylococcus aureus (MRSA) which were detected in our hospital. Of these strains, 6 strains showed resistant to Teicoplanin (TEIC) which MIC level were between 4 to 8microg/mL. All of them showed some phenotype, such as type II of coagulase, type A of enterotoxin, and were producing TSST-1.