Molecular Epidemiology of Carbapenem-Resistant Klebsiella aerogenes in Japan.

Information regarding Klebsiella aerogenes haboring carbapenemase in Japan is limited. A comprehensive nationwide survey was conducted from September 2014 to December 2022, and 67 non-duplicate strains of carbapenem-resistant K. aerogenes were isolated from 57 healthcare facilities in Japan. Through genetic testing and whole-genome sequencing, six strains were found to possess carbapenemases, including imipenemase (IMP)-1, IMP-6, New Delhi metallo-ß-lactamase (NDM)-1, and NDM-5. The strain harboring blaNDM-5 was the novel strain ST709, which belongs to the clonal complex of the predominant ST4 in China. The novel integron containing blaIMP-1 featured the oxacillinase-101 gene, which is a previously unreported structure, with an IncN4 plasmid type. However, integrons found in the strains possessing blaIMP-6, which were the most commonly identified, matched those reported domestically in Klebsiella pneumoniae, suggesting the prevalence of identical integrons. Transposons containing blaNDM are similar or identical to the transposon structure of K. aerogenes harboring blaNDM-5 previously reported in Japan, suggesting that the same type of transposon could have been transmitted to K. aerogenes in Japan. This investigation analyzed mobile genetic elements, such as integrons and transposons, to understand the spread of carbapenemases, highlighting the growing challenge of carbapenem-resistant Enterobacterales in Japan and underscoring the critical need for ongoing surveillance to control these pathogens.

Undiagnosed Perihepatic Abscess Revealed at Autopsy of a Patient With COVID-19 Undergoing Prolonged Extracorporeal Membrane Oxygenation (ECMO) Therapy.

The use of extracorporeal membrane oxygenation (ECMO) increased during the COVID-19 pandemic. However, complications associated with the long-term use of ECMO are poorly understood. This case report describes the autopsy findings of a perihepatic abscess in a patient with long-term COVID-19, which could not be diagnosed before death. In cases where the source of infection remains elusive but uncontrolled infections occur, we recommend the combined use of ultrasonography and contrast-enhanced computed tomography (CT) in patients with COVID-19 undergoing prolonged ECMO support, with particular consideration given to the potential development of cholecystitis.

A cluster of Candida parapsilosis displaying fluconazole-trailing in a neonatal intensive care unit successfully contained by multiple infection-control interventions.

Objective: This study aimed to investigate and contain a cluster of invasive candidiasis cases caused by fluconazole-resistant Candida parapsilosis (FRC) in a neonatal intensive care unit. Methods: Active surveillance was initiated. Direct observations of hand-hygiene compliance (HHC) among staff were conducted before and after the implementation of hand-hygiene (HH) education. Thirty-five environmental cultures were obtained. Phylogenetic analysis of FRC was performed using Fourier-transform infrared spectroscopy and microsatellite genotyping. Results: A total of 14 patients (mean birth weight = 860 g, gestational age = 25 weeks) infected with FRC were identified using the fully automated analyzer, including 5 with clinical infection (three with catheter-related bloodstream infection, one with cutaneous infection, and one with fatal peritonitis) and 9 with colonization. The HHC rate in nurses before performing a sterile or aseptic procedure significantly improved after the HH education (P < .05). Sinks near the patients were contaminated with FRC. All FRC strains were confirmed to be susceptible to fluconazole using the CLSI method, and the microdilution procedure indicated a trailing effect. Phylogenetic analysis showed that all the fluconazole-trailing isolates from patients were clustered together and had the same genotype. Sinks were successfully decontaminated using accelerated hydrogen peroxide and drainage pipes were replaced. Ultraviolet-C decontamination was applied in the milk preparation room. No new cases were detected after the education and disinfection interventions. Conclusions: Sinks are an important reservoir of C. parapsilosis. Active surveillance, environmental hygiene, and constant staff education on maintaining a high level of HHC are necessary to limit the spread of C. parapsilosis.

Clinical characteristics and outcomes of persistent bacteremia in patients with head and neck cancer in a tertiary care hospital.

Introduction: Compared to other cancers, research on bloodstream infection in head and neck cancer is scarce, lacking comparative studies on persistent versus transient bacteremia outcomes. Methods: This retrospective survey examined patients with head and neck cancer undergoing blood culture at our center from June 2009 to May 2023. Blood culture-positive cases suspected of infection were divided into persistent bacteremia and transient bacteremia groups. We investigated their clinical, epidemiological, and microbiological features, including risk factors for persistent bacteremia and mortality. The primary outcome was 90-day mortality. Results: In this 97-patient cohort, 14 (14%) cases were assigned to the persistent bacteremia group. Catheter-related bloodstream infections were the leading cause of infection in both groups, consistently contributing to a high proportion of overall bloodstream infections. The mortality rate was generally higher in the persistent bacteremia group than in the transient bacteremia group (odds ratio [OR], 2.6; 95% confidence interval [CI], 0.6-11.1), particularly in the non-clearance subgroup (OR, 9; 95% CI, 0.5-155.2). Pyogenic spondylitis was a key risk factor for persistent bacteremia, while hypoalbuminemia increased mortality. Conclusion: In patients with bacteremia and head and neck cancer, persistent bacteremia was associated with higher mortality than was transient bacteremia. Adittionally, bacteremia clearance in persistent bacteremia is thus crucial for prognostic improvement.