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.

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.

[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.

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.