Research Article Endemicity of Acinetobacter calcoaceticus-baumannii Complex in an Intensive Care Unit in Malaysia Amreeta Dhanoa, 1 Ganeswrie Rajasekaram, 2 Soo Sum Lean, 3 Yuet Meng Cheong, 1 and Kwai Lin Thong 3 1 Jefrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Bandar Sunway, Malaysia 2 Department of Pathology, Hospital Sultanah Aminah Johor Bahru, 80100 Johor Bahru, Malaysia 3 Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia Correspondence should be addressed to Kwai Lin hong; thongkl@um.edu.my Received 18 August 2015; Revised 22 November 2015; Accepted 25 November 2015 Academic Editor: Hin-Chung Wong Copyright © 2015 Amreeta Dhanoa et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Introduction. Acinetobacter calcoaceticus-baumannii complex (ACB complex) is a leading opportunistic pathogen in intensive care units (ICUs). Efective control of spread requires understanding of its epidemiological relatedness. his study aims to determine the genetic relatedness and antibiotic susceptibilities of ACB complex in an ICU in Malaysia. Methodology. Pulsed ield gel electrophoresis (PFGE), E-test, and disk difusion were used for isolates characterization. Results. During the study period (December 2011 to June 2012), 1023 patients were admitted to the ICU and 44 ACB complex (blood,  = 21, and blind bronchial aspirates,  = 23) were recovered from 38 ICU patients. Six isolates were from non-ICU patients. Of the 44 ICU isolates, 88.6% exhibited multidrug-resistant (MDR) patterns. here was high degree of resistance, with minimum inhibitory concentration 90 (MIC 90 ) of >32 g/mL for carbapenems and ≥256 g/mL for amikacin, ampicillin/sulbactam, and cefoperazone/sulbactam. Isolates from the main PFGE cluster were highly resistant. here was evidence of dissemination in non-ICU wards. Conclusion. High number of clonally related MDR ACB complex was found. While the ICU is a likely reservoir facilitating transmission, importation from other wards may be important contributor. Early identiication of strain relatedness and implementation of infection control measures are necessary to prevent further spread. 1. Introduction he genus Acinetobacter comprises Gram-negative, strictly aerobic, nonmotile, non-lactose-fermenting, oxidase-nega- tive, catalase-positive coccobacilli [1]. Members of the Acine- tobacter calcoaceticus-baumannii complex (ACB complex) [2, 3] are the predominant Acinetobacter in clinical settings. Healthcare-associated infections caused by Acinetobacter baumannii are increasingly seen among immunocompro- mised populations and frequently cause outbreaks [1–3]. Acinetobacter spp. are among the most common isolates from intensive care units (ICUs) in most Malaysian hospitals [4]. he challenge of managing infections caused by Acinetobacter baumannii has been complicated by the emergence and spread of multidrug-resistance (MDR), with both endemic and epidemic occurrences [1, 2]. Hospital acquired pneumonia associated with Acinetobacter spp. in Asian countries showed very high rate of resistance to imipenem at 67.3%, with especially high rates in Malaysia (86.7%), hailand (81.4%), India (85.7%), and China (58.9%) [5]. In addition to the selection pressure exerted by widespread antibiotics usage, increased spread of MDR Acinetobacter baumannii may result from transmissions of resistant strains via contaminated surfaces, objects, and colonized healthcare workers [1–3, 6–8]. It is believed that infection relects only the tip of an iceberg, with colonization relecting the submerged portion [3, 9]. From an epidemiological perspective, it is useful to determine the relatedness (clonality) of these organisms, especially in endemic situations and epidemic outbreaks. If these strains Hindawi Publishing Corporation Journal of Pathogens Volume 2015, Article ID 789265, 8 pages http://dx.doi.org/10.1155/2015/789265