Clinical and microbiologic characteristics of cefotaxime-non-susceptible Enterobacteriaceae bacteremia: a case control study. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: Noguchi, Taro; Matsumura, Yasufumi; Yamamoto, Masaki; Nagao, Miki; Takakura, Shunji; Ichiyama, Satoshi
• Is Part Of: BMC infectious diseases. Volume 17:Issue 1(2017)
• Page Start: 1
• Page End: 9
• Publication Date: 2017-12
• Subjects: Enterobacteriaceae -- Cefotaxime-non-susceptible -- Bacteremia; Communicable diseases -- Periodicals; Sexually Transmitted Diseases -- Periodicals; 616.905
• DOI: 10.1186/s12879-016-2150-6
• Languages: English
• ISSNs: 1471-2334

Abstract

Abstract Background Cefotaxime plays an important role in the treatment of patients with bacteremia due toEnterobacteriaceae, although cefotaxime resistance is reported to be increasing in association with extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase (AmpC). Methods We conducted a case-control study in a Japanese university hospital between 2011 and 2012. We assessed the risk factors and clinical outcomes of bacteremia due to cefotaxime-non-susceptibleEnterobacteriaceae (CTXNS-En) and analyzed the resistance mechanisms. Results Of 316 patients withEnterobacteriaceae bacteremia, 37 patients with bacteremia caused by CTXNS-En were matched to 74 patients who had bacteremia caused by cefotaxime-susceptibleEnterobacteriaceae (CTXS-En). The most common CTXNS-En wasEscherichia coli (43%), followed byEnterobacter spp. (24%) andKlebsiella spp. (22%). Independent risk factors for CTXNS-En bacteremia included previous infection or colonization of CTXNS-En, cardiac disease, the presence of intravascular catheter and prior surgery within 30 days. Patients with CTXNS-En bacteremia were less likely to receive appropriate empirical therapy and to achieve a complete response at 72 h than patients with CTXS-En bacteremia. Mortality was comparable between CTXNS-En and CTXS-En patients (5 vs. 3%). CTXNS-En isolates exhibited multidrug resistance but remained highly susceptible to amikacin and meropenem. CTX-M-type ESBLs accounted for 76% of the β-lactamase genes responsible for CTXNSE. coli andKlebsiella spp. isolates, followed by plasmid-mediated AmpC (12%). Chromosomal AmpC was responsible for 89% of CTXNSEnterobacter spp. isolates. Conclusions CTXNS-En isolates harboring ESBL and AmpC caused delays in appropriate therapy among bacteremic patients. Risk factors and antibiograms may improve the selection of appropriate therapy for CTXNS-En bacteremia. Prevalent mechanisms of resistance in CTXNS-En were ESBL and chromosomal AmpC.