Changing trends of in vitro antimicrobial resistance patterns in blood isolates in a tertiary care hospital over a period of 4 years.

ABSTRACT

Context Multidrug-resistant organisms continue to be a problem for clinicians worldwide. AIMS: To analyze the changing trend of antimicrobial susceptibility patterns in the blood isolates over a period of 4 years in our hospital. Settings and Design: This is a retrospective study done in tertiary care cardiac institute over a period of 4 years. Materials and Methods: We retrospectively analyzed blood culture positive isolates and studied the antimicrobial susceptibility patterns of microorganisms during the period starting from January 2007 to December 2010. Statistical Analysis Used Statistical analysis was conducted using SPSS for windows version 13.0. Fisher exact test or chi-square test was applied for comparison of categorical variables. P values less than .05 were considered as statistically significant. Results: The rate of blood culture positivity was 3.72%. Gram-negative bacteria were more common than Gram-positive bacteria. There was a gradual increase in Gram-negative bacteria especially Klebsiella pneumoniae and Acinetobacter species. Klebsiella pneumoniae showed a significant increase of resistance to cefoperazone sulbactam (P = .023), piperacillin tazobactam (P < 0.001), imipenem (P < 0.001), and meropenem (P < 0.001) between the first (2007-2008) and second period (2009-2010) of study. The carbapenems resistance is on rise in Gram-negative bacteria including Enterobacteriaceae and non-fermenters. Conclusions: Our findings suggest that there is a definite increase in the multidrug resistant organisms. The data on the changing trends in antibiotic resistance, we believe is an important pillar in our efforts at improving infection control practices.