Prevalence and Susceptibility Analysis of Carbapenem Resistant Gram-negative Pathogens in Super Specialty Tertiary Care Center, Mumbai, India

Aim: Taking into account the rise in mortality rate due to multi-drug resistant Gram-negative bacteria, we purposed to retrospectively analyze the susceptibility behavior of 74 carbapenem-resistant clinical isolates towards common antibiotic classes [Sulphomide, β-lactams (BL), β-lactam/β-lactamase inhibitor combination (BL/BLI), aminoglycosides, cephalosporins, quinolone, peptide and glycylcycline] and a novel antibiotic-adjutant entity, CSE-1034 [Ceftriaxone/ Sulbactam/disodium edetate].

Materials and Methods: To characterize the anti-bacterial susceptibility pattern, a retrospective, observational analysis of antibiogram data obtained from different clinical samples in Super Speciality tertiary care center, Mumbai (India) between January 2015 to December 2015 was performed. 74 carbapenem-resistant clinical isolates with MIC>16 against imipenem and meropenem were analyzed in this study. K. pneumoniae (47.30%) was found to be the most common pathogen among all clinical isolates followed by A. baumannii (17.57%), E. coli (14.86%) and P. aeruginosa (10.81%).

Results: Antibiogram data suggested colistin as the most susceptible drug against all carbapenem-resistant isolates followed by tigecycline. CSE-1034 was determined as third most susceptible drug. The susceptibility rates of K. pneumoniae, A. baumannii, E. coli and P. aeruginosa to CSE-1034 were 81.8%, 57.1%, 69.2% and 75%. The susceptibility to aminoglycosides varied from zero for A. baumanni to 63.6% for E. coli in case of amikacin and 8.57% for K. pneumoniae and 37.5% for P. aeruginosa in case of gentamicin. The susceptibility to all other antibiotics tested was very poor.

Conclusion: From this study, it can be concluded that along with colistin and tigecycline, CSE-1034 and aminoglycosides can be considered for patients infected with carbapenem-resistant strains. Moreover, CSE-1034 or aminoglycosides can be good alternates in carbapenem resistant bloodstream, and urinary tract infections as tigelcycline is not preferred agent in these infections.