Original article PDF Wonkeun Song1, Jae-Seok Kim1, Han-Sung Kim1, Tae Jae Lee1, Min-Jeong Park1, In-Heon Park2, and Kyu Man Lee1 Department of Laboratory Medicine1and Orthopedic Surgery2, Hallym University College of Medicine, Seoul, Korea Corresponding to Wonkeun Song, E-mail: swonkeun@hallym.or.kr Ann Clin Microbiol 2004;7(2):124-129.Copyright © Korean Society of Clinical Microbiology. Abstract Background : Klebsiella oxytoca strain exhibiting an unusual inducible β-lactam resistance phenotype was isolated from a wound specimen of a patient at a university hospital in August 2002. The isolate was resistant to ampicillin, ampicillin-sulbactam, cephalothin, cefoxitin, and demonstrated reduced inhibition zone diameters for ceftazidime in combination with clavulanate versus those for ceftazidime when tested alone. Methods : Antimicrobial susceptibilities were tested using the Etest and disk diffusion method. AmpC β-lactamase production was determined by modified Hodge test. The disk antagonism method was used to detect inducibility of β-lactamase. Conjugation experiments were performed by the filter mating method using the recipient Escherichia coli J53 Azir strain. PCR and

Original article PDF Wonkeun Song*, Tae Jae Lee, Taek-Kyung Kim, Han-Sung Kim, Jae-Seok Kim, Min-Jeong Park, and Kyu Man Lee Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, Korea Corresponding to Wonkeun Song, E-mail: swonkeun@hallym.or.kr Ann Clin Microbiol 2005;8(2):160-164.Copyright © Korean Society of Clinical Microbiology. Abstract Background: The aim of this study was to evaluate the Vitek system and the disk diffusion method for susceptibility testing of Enterobacteriaceae against piperacillin-tazobactam (TZP) and methicillin-resistant Staphylococcus aureus(MRSA) against trimethoprim-sulfamethoxazole (SXT) using the broth microdilution method as the reference. Methods: Using the Vitek system and the disk diffusion method, we tested 96 isolates of Enterobacteriaceae (48 Escherichia coli, 26 Klebsiella pneumoniae, 8 Serratia marcescens, 6 Enterobacter cloacae, 2 E. aerogenes, 2 K. oxytoca, 2 Citrobacter freundii, 2 Pantoea agglomerans) and 61 isolates of MRSA for susceptibity against TZP and SXT, respectively; the broth microdilution of National Committee for Clinical Laboratory Standards was used as the reference method. Results: In the susceptibility testing of Enterobacteriaceae against TZP, Vitek system yielded

Original article PDF Han-Sung Kim, Jae-Seok Kim, Wonkeun Song, Hee Jung Kang, Kyu Man Lee Department of Laboratory Medicine, Hallym University College of Medicine, Anyang, Korea Corresponding to Han-Sung Kim, E-mail: kimhan@hallym.ac.kr Ann Clin Microbiol 2007;10(1):14-18.Copyright © Korean Society of Clinical Microbiology. Abstract Background: TT virus (TTV) infection is highly prevalent in the general population and in the patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV). The aim of the present study was to assess the positive rates of TTV DNA using different PCR primer sets in healthy and HBV or HCV-infected individuals in Korea.  Methods: TTV DNA was investigated in serum samples of 69 healthy individuals and 59 HBV-infected and 34 HCV-infected individuals by nested PCR assays using primers from N22 region, 5′-untranslated region (UTR), and 3′ UTR of viral genome.  Results: TTV DNA was detected in 43% of total study populations using N22 primers,

Original article PDF Han-Sung Kim1,2, Jae-Seok Kim1, Chae-Ok Ha2, Wonkeun Song1, Kyu Man Lee1 1Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, Korea; 2Department of Laboratory Medicine, Hallym University Sacred Heart Hospital, Anyang, Korea Corresponding to Jae-Seok Kim, E-mail: jaeseok@hallym.or.kr Ann Clin Microbiol 2008;11(1):18-22.Copyright © Korean Society of Clinical Microbiology. Abstract Background: The MicroScan MICroSTREP plus panel for susceptibility testing of various streptococci, including Streptococcus pneumoniae, has recently been introduced in Korea. The current study evaluated the usefulness of MicroScan MICroSTREP plus panel for antimicrobial susceptibility test of S. pneumoniae. Methods: A total of 75 clinical isolates of S. pneumoniae were tested for antimicrobial susceptibility to penicillin, cefotaxime, ceftriaxone, meropenem, vancomycin, clindamycin, erythromycin, and levofloxacin with the MicroScan MICroSTREP plus panel and clinical and laboratory standard institute (CLSI) reference broth microdilution method. For 46 of 75 isolates, additional susceptibility tests to penicillin and cefotaxime were performed with Etest. Results: The overall essential agreement of

Research note PDF Dong-Jin Park1, Wonkeun Song1, Taek-Kyung Kim2, Jae-Seok Kim1, Han-Sung Kim1, Kyu Man Lee1 Department of Laboratory Medicine, 1Hallym University College of Medicine, 2Kangnam Sacred Heart Hospital, Seoul, Korea Corresponding to Wonkeun Song, E-mail: swonkeun@hallym.or.kr Ann Clin Microbiol 2009;12(3):144-145.Copyright © Korean Society of Clinical Microbiology. Abstract We collected 76 clinical isolates of Acinetobacter baumannii (amikacin MIC by Vitek 2 AST-N055 card: ≤2μg/mL, 11 isolates; 4μg/mL, 19 isolates; 8μg/ mL, 17 isolates; 16μg/mL, 27 isolates; and ≥64μg/ mL, 2 isolates) from a university hospital and evaluated the Vitek 2 AST-N055 card vs the broth microdilution as a reference method for testing susceptibility to amikacin. Vitek 2 AST-N055 card yielded very major errors in 15 isolates (19.7%) and minor errors in 26 isolates (34.2%). Of the 15 isolates shown very major errors, 14 had Vitek 2 MICs ranging from 8 to 16μg/mL. The results of our study suggest strongly that it is unreliable to

Original article PDF Yong-Kyun Kim1, Jae-Seok Kim1,3, Hyoung-Sun Lee2, Hyun-Sook Koo3, Han-Sung Kim1, Wonkeun Song1, Ji Young Park1, Hae-Ran Lee4, Hyoun Chan Cho1, Kyu Man Lee1 Departments of 1Laboratory Medicine and 4Pediatrics, Hallym University College of Medicine, Departments of 2Laboratory Medicine and 3Infection Control Unit, Kangdong Sacred Heart Hospital, Seoul, Korea Corresponding to Jae-Seok Kim, E-mail: jaeseok@hallym.or.kr Ann Clin Microbiol 2009;12(1):43-47.Copyright © Korean Society of Clinical Microbiology. Abstract Background: Doctors’ white coats and neckties can become contaminated with potentially pathogenic bacteria and have a possibility of causing cross infections. Our objective was to determine the level of bacterial contamination and detect methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and Clostridium difficile present on the white coats and neckties of residents.  Methods: We sampled 28 long-sleeved white coats and 14 neckties worn by residents. The tested sites for white coats were the cuffs and lower front surfaces, and for neckties, the lower surfaces. Impressions of these sites were taken

Original article PDF Aerin Kwon, Jae-Seok Kim, Han-Sung Kim, Wonkeun Song, Ji-Young Park, Hyoun Chan Cho, Kyu Man Lee Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, Korea Corresponding to Jae-Seok Kim, E-mail: jaeseok@hallym.or.kr Ann Clin Microbiol 2010;13(3):109-113. https://doi.org/10.5145/KJCM.2010.13.3.109Copyright © Korean Society of Clinical Microbiology. Abstract Background: Novel swine influenza (H1N1) was first identified in Mexico in April 2009. Because of its high infectivity and worldwide distribution, a rapid and efficient screening test is necessary. Here we evaluated the usefulness of a rapid antigen test currently in use, compared to real-time RT-PCR (rRT-PCR) as a screening test for detection of novel swine influenza (H1N1).  Methods: A total of 1,228 patients who visited Hallym University Kangdong Sacred Heart Hospital with influenza-like illness between 14 August 2009 and 30 September 2009, and were tested by both rapid antigen and rRT-PCR tests, were enrolled in this study.  Results: Sensitivity, specificity, predictive

Original article PDF Hye Young Yun1, Han-Sung Kim1,2, Young Kyung Lee1,2, Hee Jung Kang1,2, Jae-Seok Kim2, Wonkeun Song2, Kyu Man Lee2 Hye Young Yun1, Han-Sung Kim1,2, Young Kyung Lee1,2, Hee Jung Kang1,2, Jae-Seok Kim2, Wonkeun Song2, Kyu Man Lee2 Corresponding to Han-Sung Kim, E-mail: kimhan@hallym.ac.kr Ann Clin Microbiol 2011;14(3):97-103. https://doi.org/10.5145/KJCM.2011.14.3.97Copyright © Korean Society of Clinical Microbiology. Abstract Background: The inhibition rates for nucleic acid tests of Mycobacterium tuberculosis have been reported to range from less than 1% to more than 10%. Specimen dilution, boiling, addition of bovine serum albumin (BSA), and a silica membrane can be used to override amplification inhibitors in nucleic acid tests of M. tuberculosis. The inhibition rate for real-time PCR of M. tuberculosis (COBAS TaqMan MTB test; Roche Diagnostics, Manheim, Germany) and effective strategies to override PCR inhibitors were investigated in this study.  Methods: The inhibition rate for COBAS TaqMan MTB test was investigated in 980