BackgroundThe purpose of this study was to identify the clinical characteristics and outcomes of peripheral vascular catheter-related bloodstream infections (PVC-BSIs) and determine the risk of severe complications or death.MethodsWe performed a retrospective observational study from June 2010 to April 2015 at two regional university-affiliated hospitals in Tokyo. We studied the clinical manifestations, underlying diseases, laboratory results, treatment methods, recurrence rates, and complications in 62 hospitalized patients diagnosed with PVC-BSIs by positive blood cultures.ResultsThe median time from admission to bacteremia was 17 days (range, 3–142 days) and that from catheter insertion to bacteremia diagnosis was 6 days (range, 2–15 days). Catheter insertion sites were in the arm in 48 (77.4%) patients, in the foot in 3 (4.8%) patients, and in an unrecorded location in 11 (17.7%) patients. Additionally, the causative pathogens were Gram-positive microorganisms in 58.0% of cases, Gram-negative microorganisms in 35.8% of cases, Candida spp. in 6.2% of cases, and polymicrobials in 25.8% of cases. Eight (12.9%) patients died within 30 days of their blood culture becoming positive. Patients who died of PVC-BSIs had a higher proportion of Staphylococcus aureus infection than patients who survived (odds ratio, 8.33; p = 0.004).ConclusionsPVC-BSIs are a significant cause of health care-associated infection. We observed cases of severe PVC-BSI requiring intensive and long-term care along with lengthy durations of antibiotic treatment due to hematogenous complications, and some patients died. For patients with PVC-BSIs, S. aureus bacteremia remains a major problem that may influence the prognosis.

Several antibiotic combinations have demonstrated increased activity against multidrug-resistant Pseudomonas aeruginosa (MDRP) in vitro compared with a single antibiotic. The aim of this study was to investigate the activity against MDRP of some aminoglycosides in combination with monobactam, piperacillin (PIPC), and carbapenem. Clinical isolates of MDRP were collected between November 2010 and October 2012 from patients in Tokyo Medical University Hospital, Tokyo (1,015 beds). Our new method was designed to evaluate three concentrations around the breakpoint of each drug using the Checkerboard method. The aminoglycosides tested were amikacin (AMK), tobramycin (TOB), and arbekacin (ABK). Ciprofloxacin, PIPC, and biapenem (BIPM), which have been reported to demonstrate combination effects, were also tested. Sixty-six MDRP strains were identified from the 2,417 P. aeruginosa strains. Of the 66, 27 tested positive for metallo-β-lactamase (MBL). Aztreonam (AZT) with AMK or ABK was the most effective against MDRP. PIPC with AMK or ABK were somewhat effective. AZT with AMK or ABK were more effective against MBL-positive strains than MBL-negative strains. However, PIPC with AMK or ABK were more effective against MBL-negative strains than MBL-positive strains. Combination activities showed differences between MBL-positive and MBL-negative strains.

BackgroundCupriavidus gilardii is an aerobic, Gram-negative, glucose-nonfermenting rod that was first identified in 1999. Because of the difficulty in accurate species identification of C. gilardii, there are few case reports of infection caused by this organism. In previous reports, C. gilardii has been characterized as an organism with low pathogenicity that causes opportunistic infections.Case presentationWe encountered a case of pacemaker-associated bloodstream infection caused by C. gilardii in a 90-year old woman without obvious immunodeficiency. We identified the isolates as C. gilardii by sequencing of the 16S rRNA gene. The patient was treated with removal of the lead and administration of antimicrobial agents. Because of the acquisition of antibiotic resistance during antibiotic treatment, the antimicrobial agent was changed during the course of treatment.ConclusionsTo our knowledge, this is the first report of an infection caused by this organism in a patient without obvious immunodeficiency. Although the true pathogenicity of C. gilardii is unclear, the possibility that it exerts pathogenicity not only in persons with immunodeficiency but also in immunocompetent persons is suggested.