Prevalence and Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa in a Tertiary Care Hospital

Pseudomonas aeruginosa (P. aeruginosa) is a major nosocomial pathogen, which causes infections such as pneumonia, urinary tract infections, surgical site infections and bacteremia. It accounts for 9–10% of hospital infections. Despite availability of newer antimicrobial agents possessing anti-Pseudomonal activities, P. aeruginosa is still responsible for causing life threatening infection in hospitals. The present study was conducted to find out the prevalence and antimicrobial susceptibility pattern of P. aeruginosa isolates obtained from various clinical samples at our hospital. The information would be helpful for physicians in selecting an appropriate antimicrobial. This was a retrospective study conducted in a tertiary care hospital in South India in March 2013. Data was obtained from the microbiology records from June 2010 to June 2012. Samples were collected from various medical and surgical wards. Samples were obtained from urine, pus, urine, pleural fluid, sputum, blood, vaginal swab, stool, ascitic fluid, throat swab, cerebrospinal fluid. The identification of P. aeruginosa using standard tests. Antimicrobial susceptibility testing was done by Kirby-Bauer's disc diffusion method, with anti-microbials having anti-Pseudomonal activities. A total of 648 samples were analyzed, out of which 177 (18.6%) were positive for P. aeruginosa. Maximum isolates were from Pus and Sputum samples and least isolates from Vaginal swab and Cerebrospinal fluid. Maximum resistance was seen with Cephalosporin group (Cefuroxime 69.4%) and least with Imipenem (3.9%) and Aztreonam (11.8%). The resistance to Quinolone group of antibiotics was high (61%). Among the Aminoglycosides, least resistance was seen with Amikacin. Antimicrobial surveillance should be done periodically to monitor the current susceptibility patterns in local hospitals. In most hospitals, sensitivity reports are not readily available, empirical therapy is often needed to treat the life threatening infections. Regional antibiotic susceptibility studies will help in choosing an appropriate antibiotic for empirical therapy and reduce the mortality and morbidity associated with P. aeruginosa infections.