Resistance Trends among Pseudomonas aeruginosa Isolates in a Tertiary Care Centre in South Gujarat

It is necessary to determine the susceptibility pattern of clinical isolates especially nosocomial one in the clinical settings for making strategy for effective empirical treatment & to reduce incidence of multidrug resistant bugs. Aim of this study was to detect the antimicrobial susceptibility pattern of P. aeruginosa isolates from clinical samples between January 2014 to December 2015, received at department of Microbiology, GMC, Surat. Clinical isolates were confirmed as P. aeruginosa by phenotypic methods/Vitek2 compact system as per availability. Genetic sequencing could not be performed due to unavailability. Antimicrobial susceptibility tests were performed by Kirby-Bauer disc diffusion method/Vitek2 compact system & Interpretation was done according Clinical and Laboratory Standards Institute (CLSI) of that year [1] [2]. Seven hundred fifty seven P. aeruginosa strains were studied during the study period. Most of the isolates were from surgery ward (62%), followed by orthopaedic ward (15%). 65% of the total isolates were from swab samples followed by urine (7%), pus, fluid (5%) & devices (4%). 60% isolates were resistant to Ceftazidime & for other drugs resistance pattern was as follows: Cefepime (52%), Levofloxacin (49%), Ticarcillin/clavulanic acid (49%), Meropenem & Gentamycin (44%), Ciprofloxacin (43%), Amikacin (41%), Tobramycin (39%), Netlimycin (36%), Piperacillin (32%), Aztreonam (31%), Piperacillin/tazobactam (26%), Imipenem (23%) , Doripenem (12%) & Gatifloxacin (10%). As there is predominance of isolates from surgical ward in present study & resistance to carbapenem group of drugs was also found, indicating that most of the infection caused by Pseudomonas aeruginosa may be nosocomial.