Original article PDF Chang-Ki Kim1, Jong Hwa Yum2, Dongeun Yong3,4, Seok Hoon Jeong3,4, Kyungwon Lee3,4, Yunsop Chong3,4 1Korean Institute of Tuberculosis, The Korean National Tuberculosis Association, Seoul; 2Department of Biomedical Laboratory Science, Dong-Eui University College of Natural Science, Busan; 3Department of Laboratory Medicine and 4Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea Corresponding to Kyungwon Lee, E-mail: leekcp@yuhs.ac Ann Clin Microbiol 2008;11(2):90-97.Copyright © Korean Society of Clinical Microbiology. Abstract Background: Clinical isolates of AmpC β-lactamase- producing Enterobacteriaceae were evaluated to determine the prevalence of CTX-M extended-spectrum β-lactamases (ESBLs) and their genetic environments. Methods: A total of 250 non-duplicate isolates of Eneterobacter aerogenes, E. cloacae, Citrobacter freundii, Serratia marcescens and Morganella morganii were collected at a Korean hospital. ESBL production was determined by double disk synergy test. For ESBL producers, bla genes were sequenced and blaCTX-Menvironment was characterized by PCR mapping and sequencing. Results: Among the 250 isolates 29 (11.6%) produced ESBL, and 14 of the 29 isolates produced CTX-M ESBLs, including CTX-M-9 by

Original article PDF Sue Jung Kim1, Heejung Kim1, Myung Sook Kim1, Eunmi Koh1, Chang-Ki Kim2, Seok Hoon Jeong1, Yunsop Chong1, Kyungwon Lee1 1Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine; 2Korean Institute of Tuberculosis, Seoul, Korea Corresponding to Kyungwon Lee, E-mail: leekcp@yuhs.ac Ann Clin Microbiol 2008;11(2):112-116.Copyright © Korean Society of Clinical Microbiology. Abstract Background: Toxin immunoassay is widely used for rapid diagnosis of Clostridium difficile-associated diarrhea. The aim of this study was to evaluate the performance of Tox A/B Quik Chek test (TECHLAB, Blacksburg, VA, USA) compared to toxigenic culture. Methods: From September 2006 to August 2007, 959 stools were examined by Tox A/B Quik Chek test and toxigenic culture (C. difficile culture plus tcdB PCR using colonies obtained from culture). Results: Compared to the results of toxigenic culture, the sensitivity and specificity of Tox A/B Quik Chek test were 47.5% and 97.5%, respectively. Conclusion: The sensitivity

Review article PDF Chang-Ki Kim1, Chulhun L. Chang2 1Korean Institute of Tuberculosis, Seoul, 2Department of Laboratory Medicine, Pusan National University School of Medicine, Yangsan, Korea Corresponding to Chulhun L. Chang, E-mail: cchl@pusan.ac.kr Ann Clin Microbiol 2009;12(4):147-153.Copyright © Korean Society of Clinical Microbiology. Abstract Clinical microbiology laboratories play a critical role in diagnosing tuberculosis (TB) and monitoring its treatment. Poor quality laboratory services remain a major barrier to diagnosis by microscopy and culture, and may complicate the interpretation of drug susceptibility testing (DST) results. External quality assessment (EQA) for microscopy is an important component of quality assurance, and includes panel testing, slide rechecking, and on-site supervision. Periodic panel testing is the simplest way to assess the performance of laboratories. Rechecking of a sample of routine smears by a higher-level laboratory is the method of choice for evaluation and continuous motivation of peripheral laboratories. On-site supervision allows the observation of workers’ performance under

Original article PDF Kyoung Ho Roh1, Chang-Ki Kim2, Jong Hwa Yum3, Dongeun Yong4,5, Seok Hoon Jeong4,5, Chae Seung Lim1, Chang Kyu Lee1, Yunjung Cho1, Kyungwon Lee4,5, Yunsop Chong4,5 1Department of Laboratory Medicine, Korea University College of Medicine, 2Korean Institute of Tuberculosis, Seoul, 3Department of Clinical Laboratory Science, Dongeui University, Busan, 4Department of Laboratory Medicine and 5Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea Corresponding to Kyungwon Lee, E-mail: leekcp@yuhs.ac Ann Clin Microbiol 2010;13(1):27-33. https://doi.org/10.5145/KJCM.2010.13.1.27Copyright © Korean Society of Clinical Microbiology. Abstract Background: Increasing numbers of Acinetobacter spp. resistant to multiple drugs, including carbapenem, has been a serious problem. The aims of this study were to determine carbapenem resistance patterns and mechanisms, as well as to study the molecular epidemiology of Acinetobacter spp. Methods: Clinical isolates of Acinetobacter spp. were collected from May to November in 2006. Antimicrobial susceptibility testing was performed using CLSI disk diffusion and

Review article PDF Chang-Ki Kim1, Heungsup Sung2, Yeon-Joon Park3, Chulhun L . Chang4 1Department of Laboratory Medicine, Korean Institute of Tuberculosis, Osong, Department of Laboratory Medicine, 2Asan Medical Center, University of Ulsan College of Medicine, Seoul, 3College of Medicine, The Catholic University of Korea, Seoul, 4Pusan National University School of Medicine, Yangsan, Korea Corresponding to Chulhun L. Chang, E-mail: cchl@pusan.ac.kr Ann Clin Microbiol 2013;16(2):61-68. https://doi.org/10.5145/ACM.2013.16.2.61Copyright © Korean Society of Clinical Microbiology. Abstract There are several problems in mycobacterial detection and drug susceptibility testing. One problem is that some test results are unnecessarily delayed because the tests are postponed until patients revisit clinics and pay the cost of the tests. Another problem is that critical and important tests are not requested because patients do not agree with their necessity. These inefficient practices may be due to the fee-for-service policy that the Korean medical insurance system is adopting and because many test

Original article PDF Chang-Ki Kim1,3, Byung Soo Lee1, Myung Joon Choi1, Hee Jin Kim1, Kyungwon Lee2,3 1Korean Institute of Tuberculosis, 2Department of Laboratory Medicine, 3Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea Corresponding to Kyungwon Lee, E-mail: leekcp@yuhs.ac Ann Clin Microbiol 2014;17(3):80-85. https://doi.org/10.5145/ACM.2014.17.3.80Copyright © Korean Society of Clinical Microbiology. Abstract Background: Fluoroquinolones (FQs) are important drugs for treating multidrug-resistant tuberculosis (MDR-TB). However, due to widespread use of FQs, the resistance rates to FQs have been increasing among Mycobacterium tuberculosis. Rapid and reliable FQ drug susceptibility testing (DST) is crucial for successful treatment of MDR-TB. In this study, the feasibility of molecular detection of FQ resistance was evaluated. Methods: A total of 95 MDR-TB isolates were collected from Jan through Oct 2009 at the Korean Institute of Tuberculosis. DST for ofloxacin (OFL), levofloxacin, and moxifloxacin was performed using the Lowenstein-Jensen media absolute concentration method. Minimum inhibitory concentrations

Case report PDF Ja Young Lee1*, Si Hyun Kim1,2*, Jeong Hwan Shin1,2, Hyun-Kyung Lee3, Young Min Lee3, Sae Am Song1, Il Kwon Bae4, Chang-Ki Kim5, Kyung Ran Jun1, Hye Ran Kim1, Jeong Nyeo Lee1, Chulhun L. Chang6 1Department of Laboratory Medicine, 2Paik Institute for Clinical Research, and 3Department of Internal Medicine, Inje University College of Medicine, 4Department of Dental Hygiene College of Medical and Life Science, Shilla University, Busan, 5Department of Laboratory Medicine, Korean Institute for Tuberculosis, Osong, 6Department of Laboratory Medicine, Pusan National University School of Medicine, Yangsan, Korea Corresponding to Chulhun Ludgerus Chang, E-mail: cchl@pusan.ac.kr Ann Clin Microbiol 2014;17(1):23-27. https://doi.org/10.5145/ACM.2014.17.1.23Copyright © Korean Society of Clinical Microbiology. Abstract Rapidly growing mycobacteria are ubiquitous in the environment and are increasingly being recognized as opportunistic pathogens. Recently, a new species, Mycobacteium conceptionense, has been validated from the Mycobacterium fortuitum third biovariant complex by molecular analysis. However, there are few reports, and

Original article PDF Sae Am Song1*, Si Hyun Kim1,6*, Chang-Ki Kim2, Heungsup Sung3, Sunjoo Kim4, Chulhun L Chang5, Jeong Hwan Shin1,6 1Department of Laboratory Medicine, Inje University College of Medicine, Busan, 2Department of Laboratory Medicine, Korean Institute of Tuberculosis, Osong, 3Department of Laboratory Medicine, Asan Medical Center and University of Ulsan College of Medicine, Seoul, 4Department of Laboratory Medicine, Gyeongsang National University School of Medicine, Jinju, 5Department of Laboratory Medicine, Pusan National University School of Medicine, Yangsan, 6Paik Institute for Clinical Research, Inje University College of Medicine, Busan, Korea Corresponding to Jeong Hwan Shin, E-mail: jhsmile@inje.ac.kr Ann Clin Microbiol 2015;18(3):69-75. https://doi.org/10.5145/ACM.2015.18.3.69Copyright © Korean Society of Clinical Microbiology. Abstract Background: There have been steady changes and improvements in diagnostic tests for Mycobacterium tuberculosis, so it is necessary to carry out periodic surveys to understand the current situation. The aims of this study were to investigate the changes in principal practices and