Real-time PCR and statistical analyses of acrAB and ramA expression in clinical isolates of Klebsiella pneumoniae

Clinical isolates of Klebsiella pneumoniae were tested for a correlation between tigecycline MIC and expression of ramA by using real-time PCR. At MICs of 4 and 8 mu g/ml, the expression of ramA was statistically significantly different from MICs of 2 mu g/ml or less, supporting the tigecycline susceptibility breakpoint of <= 2 mu g/ml for K. pneumoniae.