AbstractBackground: Citrobacter is a Gram negative, non- sporing bacillus belonging to the family of Enterobacteriaceae. Citrobacter species are primary inhabitants of intestinal tract, often found in human faces. They can also be found in soil, sewage, food, and animal feces. Nowadays Citrobacter species are emerging as important nosocomial pathogens due to reduced host defences leading to urinary tract infections, neonatal sepsis, pulmonary infections, brain abscess, meningitis and blood stream infections. In health care settings, Citrobacter species have become an increasing cause of concern as they are becoming multidrug resistant (MDR) leading to high morbidity and mortality in the patients. Objectives: to assess the antibiotic resistance pattern of Citrobacter species isolated from various clinical samples at VIMS hospital, Ballari. Materials and Methods: A retrospective study was done on results of culture and antimicrobial susceptibility of isolates of Citrobacter species from urine, pus, sputum and blood samples obtained for a duration of 6 months, at VIMS, Ballari. Samples were processed for routine microscopy and culture and Citrobacter specieswere identified by standard methods. Antimicrobial susceptibility testing was performed as per CSLI guidelines by Kirby-bauer disc diffusion method. Results: Out of 82 isolates of Citrobacter spp, majority were from urine (63.4%), followed by sputum (17%), pus (13.4%) and blood (6%). The prevalence of Citrobacter infections was high among male patients (58.5%) than females (41.4%). Citrobacter koseri was the predominant species 56 (68.2%) isolated. Anti-biograms of Citrobacter isolates revealed that effective antimicrobial agent against Citrobacter isolates was imipenem (91.8% sensitive), followed by Piperacillin/Tazobactam (58.3%) and Amikacin (53.4%). Conclusion: Citrobacter spp are emerging as one of the important pathogens causing nosocomial infections. Emergence of multi-drug resistant Citrobacter species is also alarmingly high. Hence routine monitoring of drug susceptibility pattern of the isolates in a particular area helps to identify the resistance trend prevalent in that particular area which in turn helps to suggest empirical treatment options to the clinicians.
Keywords: Citrobacter species; Gram negative bacilli; Bacterial flora; Multidrug resistance nosocomial infections; Antimicrobial resistance.