2012 Volume 27 Issue 6 Pages 419-424
A total of 33 patients treated with meropenem (MEPM) at this institution between January 2007 and January 2012 following detection of P. aeruginosa infection were divided into a non-resistant group with no change of MIC or eradication of P. aeruginosa and a resistant group with increased MIC. Univariate analysis and multivariate analysis were performed using the two response variables of “non-resistance” and “resistance,” and the following eight risk factors for resistance to P. aeruginosa: age, CCr, duration of hospitalization, daily dose of MEPM, 24 hr %time above MIC (%T>MIC) of MEPM, duration of MEPM treatment, pretreatment MIC of P. aeruginosa, and admission or non-admission to the ICU. The results of univariate analysis showed significant differences with respect to two variables, “%T>MIC” and “pretreatment MIC of P. aeruginosa,” and multiple collinearity of four variables, “CCr,” “daily dose of MEPM,” “%T>MIC,” and “pretreatment MIC of P. aeruginosa.” These findings suggested that “%T>MIC” and “pretreatment MIC of P. aeruginosa” were risk factors for resistance to P. aeruginosa with a confounding relationship. Prior to administration of MEPM, the MIC of P. aeruginosa should be confirmed and treatment should be designed to prolong %T>MIC. The results of multivariate analysis did not show significant influence for any of the variables, but the small p value for “admission or non-admission to ICU” suggested that careful attention is required.