Prevalence and Susceptibility Analysis of Gram Negative Pathogens in Tertiary Care Transplant Hospital, Mumbai

Introduction: The susceptibility pattern of antibiotics varies in different geographical regions and needs to be updated regularly to guide clinicians in choosing appropriate empirical therapies. This study was aimed to evaluate the susceptibility pattern of Gram negative clinical isolates towards commonly used antibiotics and a novel antibiotic adjuvant entity, CSE-1034 (Ceftriaxone+ Sulbactam+EDTA).

Methods: A retrospective observational analysis of antibiogram was performed to characterize the susceptibility pattern of different pathogen isolates from various clinical sources. A total of 203 Gram negative isolates identified from the period June 2015 to June 2016 were included in the study.

Results: Of the total 203 gram-negative isolates, the majority were obtained from urine (44.3%) followed by respiratory specimens (12.3%), blood (12.3%), pus (9.3%) and collection/fluids (7.3%). The most predominant isolates were Escherichia coli (49.8 %) and Klebsiella pneumoniae (37.4%) whereas other pathogens contributed <5%. CSE-1034 and Meropenem were almost equally active against E. coli (85.1%: 89.1%) and K. pneumoniae (57.8%: 60.5%). The susceptibility of Acinetobacter baumannii and Pseudomonas aeruginosa to CSE-1034 was 83.3% and 66.6% whereas none of the isolates was reported Meropenem-susceptible. All the isolates of Enterobacter aerogenes, Enterobacter cloacae, and Proteus mirabilis were reported 100% susceptible towards both CSE-1034 and Meropenem.

The susceptibility towards Piperacillin-Tazobactam (Pip-Taz) was comparable to cefoperazone-Sulbactam. Pip-Taz displayed 67.3% and 46.0% and Cefoperazone-Sulbactam displayed 69.3% and 53.9% susceptibility against E. coli and K. pneumoniae. All the isolates of E. cloacae and P. mirabilis were susceptible to both Cefoperazone-Sulbactam and Pip-Taz whereas the susceptibility of other isolates varied for the two antibiotics.

Conclusion: The present study suggests that CSE-1034 may be considered as an important therapeutic option for Gram negative bacteria as monotherapy or as a part of combination therapy. It may also be considered as useful option to spare carbapenems.