Colistin has been re-introduced into clinical practice for the treatment of carbapenem-resistant Gram-negative bacteria. Studies in the last decade attempted to reconstruct the path that present-day medications undergo prior to clinical use. In this review, we summarize the results of recent clinical studies. Colistin was associated with lower mortality than no effective treatment and higher unadjusted mortality than β-lactams in non-randomized clinical studies. However, it was administered to sicker patients with carabapenem-resistant bacteria. Overall, nephrotoxicity rates were not higher with colistin in these studies, and colistin-induced nephrotoxicity is reversible in most patients. The emergence of colistin resistance has been described in high-use settings. Synergy with carbapenem, rifampin and other antibiotics has been reported in vitro. Randomized controlled trials are ongoing or in planning to assess this and other aspects of colistin use in clinical practice.

BACKGROUND Patients with cancer are at increased risk of developing complications of influenza. In this study, the authors assessed the effectiveness of influenza vaccination among cancer patients. METHODS A prospective, noninterventional cohort study was conducted during the 2010 to 2011 influenza season. The cohort included adult cancer patients with solid malignancies who were receiving chemotherapy and hematologic patients who had active disease. Patients who died between October and November 2010 (N = 43) were excluded. A comparison was made between patients who received the 2011 seasonal influenza vaccine with those who did not. The primary outcome was a composite of hospitalizations for fever or acute respiratory infections, pneumonia, and/or infection‐related chemotherapy interruptions. All‐cause mortality was a secondary outcome. A propensity‐matched analysis was conducted based on the propensity for vaccination. RESULTS Of 806 patients who were included, 387 (48%) were vaccinated. Factors that were associated independently with vaccination included past influenza vaccination, past pneumococcal vaccination, >6 months since cancer diagnosis, country of birth, and cancer type/status. The primary outcome occurred in 111 of 387 (28.7%) vaccinated patients versus 112 of 419 (26.7%) unvaccinated patients (P = .54). No association was observed between vaccination and the primary outcome in a propensity‐matched analysis (N = 436) or during peak influenza activity. The mortality rate was 11.9% (46 of 387 patients) in vaccinated patients versus 19.1% (80 of 419 patients) in unvaccinated patients (P = .005). Vaccination retained a significant association with mortality on multivariable analysis (odds ratio, 2.31; 95% confidence interval, 1.4‐3.79) and in a propensity‐matched analysis (odds ratio, 2.39; 95% confidence interval, 1.32‐4.32). CONCLUSIONS Influenza vaccination was associated with lower mortality among cancer patients, although an association with infection‐related complications could not be demonstrated. The current results support efforts to promote influenza vaccination in patients with cancer. Cancer 2013;119:4028–4035. © 2013 American Cancer Society.

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) incur significant costs. We aimed to examine the cost and cost-benefit of infection control interventions against MRSA and to examine factors affecting economic estimates. We performed a systematic review of studies assessing infection control interventions aimed at preventing spread of MRSA in hospitals and reporting intervention costs, savings, cost-benefit or cost-effectiveness. We searched PubMed and references of included studies with no language restrictions up to January 2012. We used the Quality of Health Economic Studies tool to assess study quality. We report cost and savings per month in 2011 US$. We calculated the median save/cost ratio and the save-cost difference with interquartile range (IQR) range. We examined the effects of MRSA endemicity, intervention duration and hospital size on results. Thirty-six studies published between 1987 and 2011 fulfilled inclusion criteria. Fifteen of the 18 studies reporting both costs and savings reported a save/cost ratio >1. The median save/cost ratio across all 18 studies was 7.16 (IQR 1.37-16). The median cost across all studies reporting intervention costs (n = 31) was 8648 (IQR 2025-19 170) US$ per month; median savings were 38 751 (IQR 14 206-75 842) US$ per month (23 studies). Higher save/cost ratios were observed in the intermediate to high endemicity setting compared with the low endemicity setting, in hospitals with <500-beds and with interventions of >6 months. Infection control intervention to reduce spread of MRSA in acute-care hospitals showed a favourable cost/benefit ratio. This was true also for high MRSA endemicity settings. Unresolved economic issues include rapid screening using molecular techniques and universal versus targeted screening.