Jemds.com Original Article J. Evolution Med. Dent. Sci./eISSN- 2278-4802, pISSN- 2278-4748/ Vol. 05/ Issue 30/ Apr. 14, 2016 Page 1553 ISOLATION AND ANTIBIOTIC SENSITIVITY PATTERN OF CITROBACTER SPECIES WITH ESBL AND AMPC DETECTION AT TERTIARY CARE HOSPITAL, BANGALORE Priyadarshini 1 , Kasukurthy Leela Rani 2 , Rajendran Ramaswamy 3 1 Post Graduate Student, Department of Microbiology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore. 2 Associate Professor, Department of Microbiology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore. 3 Professor & HOD, Department of Microbiology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore. ABSTRACT BACKGROUND Genus Citrobacter is one of the aerobic Gram negative non-sporing bacilli, from the Enterobacteriaceae family. Citrobacter koseri and Citrobacter freundii are the commonest species implicated in infections. It is emerging as an important nosocomial pathogen. It is associated with high mortality and morbidity rate. They are often resistant to routinely used antibiotics. Emerging drug resistance is a therapeutic concern for clinicians worldwide, thus isolation and antibiotic sensitivity of Citrobacter is critically needed. OBJECTIVES Identification of Citrobacter species and antibiotic sensitivity pattern with AmpC and ESBL Detection. METHODS Prospective study was done from June 2014 to March 2015. The samples were collected from patients attending VIMS and RC. The samples were processed and identified by standard protocol. Citrobacter isolates were tested for antibiotic sensitivity by Kirby-Bauer disc diffusion method as per clinical and standard institute guidelines. Detection of AmpC by Cephamycin Hodge test using Cefoxitin 30 μg with ATCC strains of Escherichia coli 25922 was done. ESBL detection was done by Ceftazidime (30 μg) and Ceftazidime/clavulanic acid (30 μg/10 μg) and Cefotaxime (30 ug) Cefotaxime/clavulanic acid (30 ug/10 ug). RESULTS Out of 5695 Gram negative isolates identified, 690 were Citrobacter isolates. Citrobacter koseri 398 (62.5%) and Citrobacter freundii 292 (37.5%) were the commonest species isolated. The antibiogram as per CLSI Guidelines showed resistance to Fluoroquinolones, Cephalosporins and beta lactamase inhibitors. Carbapenems were found to be sensitive. The resistance to beta lactamase inhibitors increased with the presence of AmpC beta lactamase (76%) and ESBL (50%). CONCLUSION Citrobacter species are emerging as an important nosocomial pathogen. Citrobacter koseri and Citrobacter freundii were the commonest species isolated. Antibiogram showing an increase in resistance among the beta lactamase inhibitors, Cephalosporins and sensitive to Carbapenems, so indiscriminate use of broad-spectrum antibiotics should be avoided and use of Carbapenems should be kept as a reserve drug. Detection of drug resistance in Citrobacter spp. will help in empirical therapy and prevent spread of infection by resistant strains. KEYWORDS Citrobacter, ESBL, Amp C. HOW TO CITE THIS ARTICLE: Priyadarshini, Rani KL, Ramaswamy R. Isolation and antibiotic sensitivity pattern of citrobacter species with ESBL and AmpC detection at Tertiary Care Hospital, Bangalore. J. Evolution Med. Dent. Sci. 2016;5(30):1553-1556, DOI: 10.14260/jemds/2016/365 INTRODUCTION Genus Citrobacter is a facultative Gram negative bacilli which belongs to Enterobacteriaceae family. These organisms were commonly isolated from variety of clinical samples like pus, sputum, urine, blood, catheter tip, tracheal aspirate. Financial or Other, Competing Interest: None. Submission 07-10-2015, Peer Review 20-03-2016, Acceptance 25-03-2016, Published 13-04-2016. Corresponding Author: Dr. Kasukurthy Leela Rani, Associate Professor, Department of Microbiology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore-66. E-mail: leela.kasukurthy@yahoo.in DOI: 10.14260/jemds/2016/365 Citrobacter species are emerging as important nosocomial pathogen with multidrug resistance, which is leading to high mortality rate. 1,2,3 Although, Citrobacter spp. are infrequent nosocomial pathogens, a local or systemic breech in the host defence can allow them to cause a range of infections. 4 It was commonly isolated from urinary tract infections, neonatal sepsis, pulmonary infections, brain abscess, meningitis and blood stream infections. Citrobacter koseri causes meningitis and brain abscess in neonates. Citrobacter freundii commonly isolated from urinary and respiratory tract infections. Citrobacter sedlakii, which causes sepsis meningitis and brain abscess. 5 They are resistant to routinely used antibiotics, especially the extended spectrum Cephalosporins, due to