Vol. 4, Issue 7, Part D (2018)

Abstract
Background & Objectives: Majority of the Gram negative pathogens causing Nosocomial infections belong to the family Enterobacteriaceae. They are normal flora in the intestine of the patients and develop antimicrobial resistance easily if antimicrobial is administered in appropriate dose. The emergence of the antimicrobial resistance in them is a therapeutic challenge. Various enzymes like ESBL, MBL etc. produced by them, make them resistant to beta lactums, the main group of antibiotic used. At present, only few drugs are available for the treatment of nosocomial infections caused by these multidrug resistant Enterobacteriaceae. Tigecycline has good therapeutic coverage against these pathogens. Thus, the study was undertaken to determine the in vitro susceptibility of the pathogens belonging to the family Enterobacteriaceae to tigecycline, especially to ESBL producers. Methods: This was a prospective study conducted at the Department of Microbiology, Father Muller Medical College Hospital during the period from January to April 2016. The clinical isolates belonging to the family Enterobacteriaceae, isolated from various samples were included in the study. The antimicrobial susceptibility pattern of the pathogen was compared with susceptibility to tigecycline. Results: A total of 271 samples were analyzed during the study period and a total of 294 pathogens were isolated belonging to enterobacteriaeceae family. The most common isolate was Escherichia coli (35.3%), followed by Klebsiella pneumoniae (24.8%). The production of ESBL was seen in 61(21%) isolates. Among the total 294 isolates included in the study, tigecycline resistance was observed in only 55 isolates (185). Among the ESBL producers, highest resistance to tigecycline was seen in Klebsiella pneumoniae followed by E.coli, 6(37.5%) and 4 (9.3%). Interpretation & Conclusions: Historically, tigecycline had a good activity against most ESBLs producing isolates. However, nowadays some ESBLs (K pneumoniae, E coli) are also shown to develop resistance against tigecycline. Hence, tigecycline cannot be used as empirical drug for the treatment of nosocomial infection. The susceptibility test for the tigecycline needs to be carried out before started it for therapeutic purpose.