title: Treatment Outcomes in Infections Caused by "SPICE" (Serratia, Pseudomonas, Indole-positive Proteus, Citrobacter, and Enterobacter) Organisms: Carbapenem versus Noncarbapenem Regimens.
abstract: Techniques used to identify AmpC β-lactamases in SPICE (Serratia, Pseudomonas, indole-positive Proteus, Citrobacter, and Enterobacter) organisms are not yet optimized for the clinical laboratory and are not routinely used. Clinicians are often left with an uncertainty on the choice of antibiotic when a SPICE organism is isolated. The purpose of this study was to evaluate the outcomes of carbapenem versus noncarbapenem regimens in treating bacteremia or urinary tract infection from a SPICE organism in clinical practice.
  
  
  
  This single-center, retrospective, cohort study analyzed data from adult patients who had clinical infection with a SPICE organism isolated from blood or urine cultures. Patients were assigned to a carbapenem- or noncarbapenem-treated group. The primary end point was clinical response, defined as a resolution of signs and symptoms of infection at the end of therapy.
  
  
  
  A total of 332 patients were assessed, and 145 patients met the inclusion criteria for the study. There were 20 patients who received a carbapenem, while 125 received a noncarbapenem regimen. The percentage of patients who were bacteremic was 46.2%. Clinical response overall was achieved in 80% of patients on a carbapenem versus 90.3% of patients on a noncarbapenem regimen (P = 0.24). The rate of microbiologic cure was 90% in patients on a carbapenem versus 91.2% in patients on a noncarbapenem regimen (P = 1).
  
  
  
  In this study in patients treated for infection with a SPICE organism in clinical practice, the rates of clinical response did not differ significantly between the carbapenem and noncarbapenem groups. Current CLSI breakpoints set for SPICE organisms may still be reliable and may not require additional testing for AmpC β-lactamases.
authors.affiliation: Department of Pharmacy, State University of New York (SUNY), Downstate Medical Center, Brooklyn, New York. Electronic address: Stanley.Moy@downstate.edu.
authors.forename: Stanley
authors.initials: S
authors.lastname: Moy
authors.affiliation: Department of Pharmacy, State University of New York (SUNY), Downstate Medical Center, Brooklyn, New York; Touro College of Pharmacy, New York, New York.
authors.forename: Roopali
authors.initials: R
authors.lastname: Sharma
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy*; D001426:Bacterial Proteins / Q000378:metabolism; D015780:Carbapenems / Q000627:therapeutic use*; D002954:Citrobacter / Q000302:isolation & purification; D004754:Enterobacter / Q000302:isolation & purification; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011511:Proteus / Q000302:isolation & purification; D011549:Pseudomonas / Q000302:isolation & purification; D012189:Retrospective Studies; D012705:Serratia / Q000302:isolation & purification; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; C048795:AmpC beta-lactamases; D001618:beta-Lactamases
keywords: AmpC β-lactamase; bacteremia; carbapenem; urinary tract infection