Vancomycin MIC Does Not Predict 90-Day Mortality, Readmission, or Recurrence in a Prospective Cohort of Adults with Staphylococcus aureus Bacteremia.
Staphylococcus aureus bacteremia (SAB) is a tremendous health burden. Previous studies examining the association of vancomycin MIC and outcomes in patients with SAB have been inconclusive. This study evaluated the association between vancomycin MICs and 30- or 90-day mortality in individuals with SAB. This was a prospective cohort study of adults presenting from 2008 to 2013 with a first episode of SAB. Subjects were identified by an infection surveillance system. The main predictor was vancomycin MIC by MicroScan. The primary outcomes were death at 30 and 90 days, and secondary outcomes included recurrence, readmission, or a composite of death, recurrence, and readmission at 30 and 90 days. Covariates included methicillin susceptibility, demographics, illness severity, comorbidities, infectious source, and antibiotic use. Cox proportional-hazards models with propensity score adjustment were used to estimate 30- and 90-day outcomes. Of 429 unique first episodes of SAB, 11 were excluded, leaving 418 individuals for analysis. Eighty-three (19.9%) participants had a vancomycin MIC of 2 μg/ml. In the propensity-adjusted Cox model, a vancomycin MIC of 2 μg/ml compared to <2 μg/ml was not associated with a greater hazard of mortality or composite outcome of mortality, readmission, and recurrence at either 30 days (hazard ratios [HRs] of 0.86 [95% confidence interval {CI}, 0.41, 1.80] [P = 0.70] and 0.94 [95% CI, 0.55, 1.58] [P = 0.80], respectively) or 90 days (HRs of 0.91 [95% CI, 0.49, 1.69] [P = 0.77] and 0.69 [95% CI, 0.46, 1.04] [P = 0.08], respectively) after SAB diagnosis. In a prospective cohort of patients with SAB, vancomycin MIC was not associated with 30- or 90-day mortality or a composite of mortality, disease recurrence, or hospital readmission.
Department of Medicine, Division of Infectious Diseases, University of California, San Francisco, San Francisco, California, USA School of Public Health, Division of Epidemiology, University of California, Berkeley, Berkeley, California, USA sanjiv.baxi@ucsf.edu.
Sanjiv M
0000-0002-2282-6140
SM
Baxi
Department of Medicine, Division of Infectious Diseases, University of California, San Francisco, San Francisco, California, USA.
Angelo
A
Clemenzi-Allen
School of Pharmacy, University of Pittsburgh Medical Center McKeesport, McKeesport, Pennsylvania, USA.
Alice
A
Gahbauer
Department of Pharmacy Services, San Francisco General Hospital, San Francisco, California, USA.
Daniel
D
Deck
Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA.
Brandon
B
Imp
Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California, USA.
Eric
E
Vittinghoff
Department of Medicine, Division of Infectious Diseases, University of California, San Francisco, San Francisco, California, USA.
Henry F
HF
Chambers
Department of Medicine, Division of Infectious Diseases, University of California, San Francisco, San Francisco, California, USA.
Sarah
S
Doernberg
D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D010359:Patient Readmission; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012720:Severity of Illness Index; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D016896:Treatment Outcome; D014640:Vancomycin / Q000627:therapeutic use*; D020713:Vancomycin Resistance
D000900:Anti-Bacterial Agents; D014640:Vancomycin