Carbapenem-Resistant Gram-Negative Bacterial Infections at a Tertiary Health Care Center in Nepal: An Observational Study.

Introduction: Carbapenems are last-resort antibiotics and are considered the drugs of choice for infections caused by multi-drug-resistant bacteria. During the last several years, there has been an alarming global increase in the detection and spread of Carbapenem-resistant organisms among gram-negative bacteria. Therefore, the main objective of this study is to determine Carbapenem-resistant gram-negative bacterial infections.

Methodology: A descriptive cross-sectional study was performed. Ethical approval was granted by the Institutional Review Committee (Reference number: CMC-IRC/080/081-071). A total of 3149 non-repeated, different clinical specimens were collected, from November 2023 to February 2024, processed aseptically under the standard protocol of the American Society for Microbiology, and screened according to the Antibiotic sensitivity pattern. The analysis of the results was performed using Microsoft Excel and manual calculations.

Results: Out of 3149 samples, 361 had culture-positive. Among 361 isolates, 316 were Gram-negative bacteria, among the specimens, 83 (26.26%) were identified as Carbapenem-resistant gram negative bacteria. Within this group, Acinetobacter baumannii was present in 37 (44.57%) cases, followed by Escherichia coli with 20 (24.09%), Klebsiella pneumoniae with 19 (22.89%), Stenotrophomonas maltophilia with 3 (4.81%), and Pseudomonas aeruginosa and Klebsiella aerogenes, each with 2 (2.40%) cases. The most effective antibiotics against Carbapenem-resistant Enterobacteriaceae included Colistin and Fosfomycin, whereas Carbapenem-resistant non-fermenter included Colistin and Tigecycline.

Conclusions: Among Carbapenem-resistant Organisms, Acinetobacter baumannii was most prevalent. The results revealed a significant proportion of infections resistant to commonly used antibiotics, highlighting an alarming trend in antibiotic resistance.