Elevated Vancomycin MICs Not Linked to Higher Mortality
(HealthDay News) — No association has been detected between vancomycin minimum inhibitory concentration (MIC) and mortality among patients with Staphylococcus aureus bacteremia (SAB), according to research published online October 9 in the Journal of the American Medical Association. The research was published to coincide with the annual meeting of the Infectious Diseases Society of America (IDWeek), held from October 8–12 in Philadelphia.
Andre C. Kalil, MD, MPH, of the University of Nebraska in Omaha, and colleagues conducted a systematic review of the literature for studies reporting mortality and vancomycin in patients with SAB. The researchers used random-effects modeling to perform a meta-analysis of data from 38 studies involving 8,291 episodes of SAB.
The researchers found that overall mortality among patients with SAB was 26.1%. Estimated mortality for SAB episodes was 26.8% in 2,740 patients with high-vancomycin MIC (≥1.5mg/L) vs. 25.8% in 5,551 patients with low-vancomycin MIC (<1.5mg/L) (adjusted risk difference [RD], 1.6%; 95% confidence interval [CI], −2.3–5.6%; P=0.43). For methicillin-resistant S. aureus infections, mortality was 27.6% in 2,384 patients with high-vancomycin MIC vs. 27.4% in 4,848 patients with low-vancomycin MIC (adjusted RD, 1.6%; 95% CI, −2.3–5.5%; P=0.41). Subgroup analysis did not show significant differences in mortality risk for high vs. low vancomycin MIC according to study design, microbiological susceptibility assays, MIC cut-offs, clinical outcomes, duration of bacteremia, previous vancomycin exposure, or treatment with vancomycin.
"These findings should be considered when interpreting vancomycin susceptibility and in determining whether alternative antistaphylococcal agents are necessary for patients with SAB with elevated but susceptible vancomycin MIC values," the authors write.
Several authors disclosed financial ties to the biomedical industry.