Changing trends in antimicrobial susceptibility and hospital acquired infections over an 8 year period in a tertiary care hospital in relation to introduction of an infection control programme.

INTRODUCTION

Antimicrobial resistance patterns in Indian hospitals differ from that reported in Western hospitals in having a high prevalence of resistance among Gram negative bacteria and a much lower incidence of resistant Gram positive bacteria. The long term effect of infection control programs on this situation also is unclear. We attempt to describe changes in our hospital antibiogram, incidence of infections due to MDR-O and VAP/CRBSI over an 8 year period in relation to introduction and serial modifications of an infection control program.

METHODS

A retrospective review of surveillance and hospital antibiogram data over the period 2001-2008 with an accent on selected MDR-O, was undertaken. All infection control protocols and modifications were also documented over the same period.

RESULTS

We found a 65% ESBL production rate in E.coli and Klebsiella and up to 40% and 70% of Pseudomonas and Acinetobacter respectively were resistant to carbapenems. While MRSA constituted 40-50% of all Staph aureus isolates, VRE and C.difficile were rarely encountered. Carbapenem resistance in Klebsiella has begun to emerge from 2005. CRBSI were largely Gram negative with MRSA contributing 6% of all isolates only. Over the 8 year study period, infection control efforts resulted in reduced CRBSI/VAP rates, fewer MRSA infections and improved sensitivities for Pseudomonas but not for other organisms.

CONCLUSIONS

Resistance among Gram negative pathogens (especially ESBL production in Enterobacteriaceae and carbapenem resistance in Pseudomonas and Acinetoacter) is a major problem in our tertiary care hospital. On the other hand C.difficile and VRE are rarely encountered. Infection control measures were modestly effective in reducing CRBSI/ VAP rates but resistance rates among Gram negative pathogens were not significantly lowered.