Abstract
BackgroundResistance among Klebsiella pneumoniae to most antibiotics is on the rise. Tigecycline has been considered as one of the few therapeutic options available to treat multidrug-resistant bacteria. We investigated the clinical and microbiological characteristics of tigecycline non-susceptible K. pneumoniae bacteremia.MethodsAdult patients with tigecycline non-susceptible K. pneumoniae bacteremia at a medical center in Taiwan over a 3-year period were enrolled. K. pneumoniae isolates were identified by the E-test using criteria set by the US Food and Drug Administration (FDA). Data on the clinical features of patients were collected from medical records. Genes for β-lactamases, antimicrobial susceptibilities and pulsed-field gel electrophoresis (PFGE) results were determined for all isolates.ResultsOf 36 patients, 27 had nosocomial bacteremia. Overall 28-day mortality was 38.9%. The MIC50 and MIC90 of tigecycline were 6 and 8 mg/L, respectively. No carbapenemase was detected among the 36 isolates. Twenty isolates carried extended spectrum β-lactamases and/or DHA-1 genes. No major cluster of isolates was found among the 36 isolates by PFGE. Intensive care unit onset of tigecycline non-susceptible Klebsiella pneumoniae bacteremia was the only independent risk factor for 28-day mortality.ConclusionsThe high mortality of patients with tigecycline non-susceptible K. pneumoniae bacteremia may suggest a critical problem. Further study to identify the possible risk factors for its development and further investigation of this type of bacteremia is necessary.
Highlights
Resistance among Klebsiella pneumoniae to most antibiotics is on the rise
We investigated the clinical and microbiological characteristics of bacteremia caused by tigecycline non-susceptible K. pneumoniae in adult patients during 2010–2012 from a medical center in Taiwan
Capsular genotype To determine the capsular genotypes of K. pneumoniae, we undertook cps genotyping by the PCR detection of K serotype-specific alleles at wzy and wzx loci, including serotypes K1, K2, K5, K20, K54, and K57, as described previously [18]
Summary
Study population This retrospective study was conducted at Taipei Veterans General Hospital (a 2900-bed tertiary-care teaching hospital) from January 2010 to December 2012. The clinical and microbiological data of all consecutive patients with ≥1 positive blood culture for K. pneumoniae strains showing non-susceptibility to tigecycline (minimum inhibitory concentration (MIC) > 2 mg/L) were collected. K. pneumoniae strains showing non-susceptibility to tigecycline (MIC >2 mg/L) according to the Vitek system were tested further by the E-test method (AB Biodisk, Solna, Sweden) according to manufacturer instructions. Data collection Medical records were reviewed to extract pertinent information, including demographic characteristics; comorbid conditions and the Charlson Comorbidity Index [20], duration of hospital stay, duration of therapy with individual antimicrobial drugs, antimicrobial therapy administrated before the onset of bacteremia, and a ventilator, central venous catheter, or a Foley catheter at the time of bacteremia onset.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have