Emergence of Tigecycline Resistance among Extended Spectrum Beta Lactamases Producing Gram-Negative Organisms

Abstract

Objective: To highlight the emergence of Tigecycline resistance among ESBL producer gram negative organisms.
Material and Methods: This cross-sectional study was conducted in Lahore College for Women University Lahore Pakistan during the period of 1^st October 2015 to 20^th March 2016. A total of 360 isolates of gram-negative rods were selected and processed for the identification of ESBL producers via double disc synergy technique. In total 100 isolates were identified as ESBL producing gram-negative rods (Escherichia coli, Klebsiella spp., Proteus spp. and Acinetobacter spp.) and were further processed for antimicrobial resistance testing against Tigecycline disks (30ug) via Kirby Bauer Disc Diffusion method.
Results: Out of 360 identified gram-negative rods, 100 (27.7%) were ESBL producers. Total 46% samples were from males and 54% from females. A maximum number of ESBL producers were recovered from pus & wound samples (54%). The most common ESBL producer was Escherichia coli followed by Klebsiella spp., Proteus spp. and Acinetobacter spp. Overall susceptibility rate of Tigecycline was 54%. Tigecycline resistance was greatest for ESBL producing Acinetobacter (n=8), followed by Proteus (n=14), Escherichia coli (n=18) and Klebsiella (n=6) (p=0.004).
Conclusion: Although tigecycline showed very good results against ESBL producers, emergence of Tigecycline resistant ESBL producers is an alarming situation.