title: Cost Attributable to Nosocomial Bacteremia. Analysis According to Microorganism and Antimicrobial Sensitivity in a University Hospital in Barcelona.
abstract: OBJECTIVE
  To calculate the incremental cost of nosocomial bacteremia caused by the most common organisms, classified by their antimicrobial susceptibility.
  
  
  METHODS
  We selected patients who developed nosocomial bacteremia caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, or Pseudomonas aeruginosa. These microorganisms were analyzed because of their high prevalence and they frequently present multidrug resistance. A control group consisted of patients classified within the same all-patient refined-diagnosis related group without bacteremia. Our hospital has an established cost accounting system (full-costing) that uses activity-based criteria to analyze cost distribution. A logistic regression model was fitted to estimate the probability of developing bacteremia for each admission (propensity score) and was used for propensity score matching adjustment. Subsequently, the propensity score was included in an econometric model to adjust the incremental cost of patients who developed bacteremia, as well as differences in this cost, depending on whether the microorganism was multidrug-resistant or multidrug-sensitive.
  
  
  RESULTS
  A total of 571 admissions with bacteremia matched the inclusion criteria and 82,022 were included in the control group. The mean cost was € 25,891 for admissions with bacteremia and € 6,750 for those without bacteremia. The mean incremental cost was estimated at € 15,151 (CI, € 11,570 to € 18,733). Multidrug-resistant P. aeruginosa bacteremia had the highest mean incremental cost, € 44,709 (CI, € 34,559 to € 54,859). Antimicrobial-susceptible E. coli nosocomial bacteremia had the lowest mean incremental cost, € 10,481 (CI, € 8,752 to € 12,210). Despite their lower cost, episodes of antimicrobial-susceptible E. coli nosocomial bacteremia had a major impact due to their high frequency.
  
  
  CONCLUSIONS
  Adjustment of hospital cost according to the organism causing bacteremia and antibiotic sensitivity could improve prevention strategies and allow their prioritization according to their overall impact and costs. Infection reduction is a strategy to reduce resistance.
authors.affiliation: IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Universitat Autònoma de Barcelona (UAB), Barcelona, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Riu
authors.affiliation: IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Universitat Autònoma de Barcelona (UAB), Barcelona, Spain.
authors.forename: Pietro
authors.initials: P
authors.lastname: Chiarello
authors.affiliation: Universitat Autònoma de Barcelona (UAB), Barcelona, Spain.|School of Nursing, Hospital del Mar, Barcelona, Spain.
authors.forename: Roser
authors.initials: R
authors.lastname: Terradas
authors.affiliation: IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Department of Epidemiology and Evaluation, Hospital del Mar, Barcelona, Spain.|Redissec (Red de Investigación en Servicios Sanitarios en enfermedades crónicas), Madrid, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Sala
authors.affiliation: IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.
authors.forename: Enric
authors.initials: E
authors.lastname: Garcia-Alzorriz
authors.affiliation: IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Department of Epidemiology and Evaluation, Hospital del Mar, Barcelona, Spain.|Redissec (Red de Investigación en Servicios Sanitarios en enfermedades crónicas), Madrid, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Castells
authors.affiliation: Universitat Autònoma de Barcelona (UAB), Barcelona, Spain.|Department of Pharmacy, Hospital del Mar, Barcelona, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: Grau
authors.affiliation: IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Cots
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000191:economics / Q000382:microbiology / Q000628:therapy; D001419:Bacteria; D003365:Costs and Cost Analysis; D003428:Cross Infection / Q000191:economics / Q000382:microbiology / Q000628:therapy; D005260:Female; D006760:Hospitalization / Q000191:economics*; D006784:Hospitals, Teaching; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013030:Spain