Prevalence and Susceptibility Profiles of Nonfermentative Gram-negative Bacilli Infection in a Tertiary Care Hospital of Eastern India.

ABSTRACT

Background: Nonfermentative gram-negative bacilli (NFGB) have emerged as a major cause of nosocomial infections.This study was undertaken to know the prevalence of nonfermenters isolated from different clinical samples along with their susceptibility profile. Material and methods: Conventional bacteriological methods were used for identification and susceptibility testing of nonfermenters. Susceptibility testing was performed by methods as recommended by Clinical Laboratory Standard Institute (CLSI). Results: Out of the total 1,650 clinical samples received NFGB were found in 201 samples with an isolation rate of 12.18%. Nonfermenters isolated were Pseudomonas aeruginosa (50.24%), Acinetobacter baumannii (24.87%), Acinetobacter lowffii (5.47%), Pseudomonas fluorescens (1.49%), Pseudomonas stutzeri (1.99%), Burkholderia cepacia (6.96%), Stenotrophomonas maltophilia (2.98%), Achromobacter xylosoxidan (3.98%) and Shewanella putrefaciens (1.99%). Most of the isolated organisms were multidrugresistant (MDR). P. aerurginosa showed good sensitivity to imipenem (91.08%), cefoperazone sulbactum (68.31%) combination, amikacin (69.30%) and colistin (100%). A. baumannii showed 90% sensitivity to imipenem and 94% to colistin. Conclusion: Our study showed that prevalence of NFGB amongst different clinical isolates is significantly high especially in this part of the world and these organisms are often MDR. In this scenario, we propose all laboratory samples should be screened for NFGB even in clinically unsuspected cases. P. aeruginosa showed good sensitivity to colistin, imipenem, amikacin and cefoperazone sulbactum combination while A. baumannii showed good sensitivity to imipenem and colistin.