Higher clinical success in patients with ventilator-associated pneumonia due to methicillin-resistant Staphylococcus aureus treated with linezolid compared with vancomycin: results from the IMPACT-HAP study

Abstract

IntroductionControversy exists regarding optimal treatment for ventilator-associated pneumonia (VAP) due to methicillin-resistant Staphylococcus aureus (MRSA). The primary objective of this study was to compare clinical success of linezolid versus vancomycin for the treatment of patients with MRSA VAP.MethodsThis was a multicenter, retrospective, observational study of patients with VAP (defined according to Centers for Disease Control and Prevention criteria) due to MRSA who were treated with linezolid or vancomycin. MRSA VAP was considered when MRSA was isolated from a tracheal aspirate or bronchoalveolar lavage. Clinical success was evaluated by assessing improvement or resolution of signs and symptoms of VAP by day 14. After matching on confounding factors, logistic regression models were used to determine if an association existed between treatment arm and clinical success.ResultsA total of 188 patients were evaluated (101 treated with linezolid and 87 with vancomycin). The mean ± standard deviation Acute Physiology and Chronic Health Evaluation (APACHE) II score was 21 ± 11 for linezolid- and 19 ± 9 for vancomycin-treated patients (P = 0.041). Clinical success occurred in 85% of linezolid-treated patients compared with 69% of vancomycin-treated patients (P = 0.009). After adjusting for confounding factors, linezolid-treated patients were 24% more likely to experience clinical success than vancomycin-treated patients (P = 0.018).ConclusionsThis study adds to the evidence indicating that patients with MRSA VAP who are treated with linezolid are more likely to respond favorably compared with patients treated with vancomycin.

Ventilator-associated pneumonia: present understanding and ongoing debates

“…Another recent meta-analysis that also included the new randomized controlled trial of linezolid versus vancomycin did find a higher microbiologic eradication rate for linezolid, and more nephrotoxicity when glycopeptides (vancomycin or teicoplanin) were used [67]. Recent data from the IMPACT-HAP study also demonstrated that patients with MRSA VAP treated with linezolid were more likely to experience clinical resolution of pneumonia than vancomycin-treated patients (p = 0.018) [68].…”

An evidence-based review of linezolid for the treatment of methicillin-resistant Staphylococcus aureus (MRSA): place in therapy

“…Whether similar results will be obtained in neutropenic human subjects remains to be elucidated. IMPACT-HAP was a retrospective, observational study of patients with ventilator-associated pneumonia (VAP) due to MRSA treated with linezolid or vancomycin 47. Patients were enrolled from five centers in the US.…”

A 2015 Update on Ventilator-Associated Pneumonia: New Insights on Its Prevention, Diagnosis, and Treatment

“…There has been considerable debate concerning the efficacy of vancomycin compared to that of linezolid for the treatment of MRSA VAP with studies demonstrating conflicting results [60][61][62][63][64]. However, in a meta-analysis by Kalil et al of RCTs, enrolling a total of 2329 patients, there was no difference in mortality between vancomycin and linezolid in treating VAP, but there was a significant increased risk of thrombocytopenia and gastrointestinal side effects with linezolid [65•].…”