Annals of Clinical Microbiology, The official Journal of the Korean Society of Clinical Microbiology


Weeks in Review


Weeks to Publication
Indexed in KCI, KoreaMed, Synapse, DOAJ
Open Access, Peer Reviewed
pISSN 2288-0585 eISSN 2288-6850

October, 2007. Vol. 10 No. 2.

Original article

Performance Evaluation of TaqMan Probe Method for BK Virus DNA Quantification by Real-time Polymerase Chain Reaction

Hee Young Chung, M.D., Yoo Li Kim, Ph.D., Kyung Ah Hwang, Ph.D., Byung Hoo Choi, M.T., Sook Ja Park, M.T., Heung Sup Sung, M.D., Mi-Na Kim, M.D.

Ann Clin Microbiol 2007 October, 10(2): 77-83. Published on 20 October 2007.

Background: We evaluated the performance of a newly developed real-time polymerase chain reaction (PCR) method using TaqMan probe (TP) and internal control (IC) for quantitation of BK virus (BKV) DNA.

Methods: PCR primers and TP were targeted for the VP1 of BKV and 300 bp-region of VP1 was cloned to prepare a standard DNA. Threshold cycles (Ct) of IC was set at 33±3. The recovery rates, precision, linearity, and limit of detection (LOD) were measured using the standard DNA. To correlate TP with previous hybridization probe (HP) method, Ct of those were compared using 35 HP-positive and 15 HP-negative specimens, and the interpretation agreement was analyzed in 63 consecutive clinical specimens including 32 urines and 31 plasmas. Fifty-three53 specimens measured for IC were analyzed for positive rates and levels of BKV according to Ct of IC.

Results: The average recovery rate was 101.1% and intra-assay and inter-assay coefficiency variations were 0.017∼0.059 and 0.036, respectively, with the specimens of 3 log/mL, and 0.041∼0.063 and 0.045, respectively, with the specimens of 6 log/mL. LOD was 183 copies/mL and linearity range was 2.7 log- 12 log/mL. Ct of TP were correlated with those of HP with the function of y=0.8912x+0.3164 (R2=0.9062). Among 63 clinical specimens, 16 were positive in TP and 12 were positive in HP with an agreement of 90.4%. Ct of IC were over 36 in 31 specimens (22 urines and 9 plasmas), of which BKV DNA was much higher in 7 (22.5%) BKV-positive specimens (5.9±1.7 log/mL) than in 4 (18.1%) BKV-positive specimens (3.9±1.0 log/mL) of 22 having Ct of IC ≤36.; 5.9±1.7 vs. 3.9±1.0 log/mL.

Conclusion: TP warrants to be a reliable method for quantification of BKV. IC seemed to be essential to differentiate false-negative results or underestimation of BKV in clinical specimens, especially in urine.

[in Korean]

Original article

Frequency of Mutation of Codon 249, Overexpression of p53, and Hepatitis B Virus DNA Positivity in Hepatocellular Carcinoma

Geon Park, M.D., Sook-Jin Jang, M.D., Ho-Jong Jeon, M.D., Seong-Hwan Kim, M.D., Mi-Ja Lee, M.D., Jin-Hee Kim, M.S., Sung-Heui Shin, M.D., Bidur Prasad Chaulagain, M.S., Dong-Min Kim, M.D., Dae-Soo Moon, M.D., Young-Jin Park, M.D.

Ann Clin Microbiol 2007 October, 10(2): 84-89. Published on 20 October 2007.

Background: In hepatocellular carcinoma (HCC), the frequency of p53 mutation and the association with hepatitis B virus (HBV) infection varies with geographic locations and risk factors. The aim of this study was to determine the frequency of codon 249 mutation of p53, p53 overexpression, and HBV DNA positivity and to observe the relationship between them in Korean HCC.

Methods: We analyzed overexpression of p53 in hepatoma tissue from 17 HCC patients by immunohistochemistry (IHC), specific mutations at the third base position of codon 249 by PCR-restriction fragment length polymorphism (PCR-RFLP) method, and presence of HBV by nested PCR.

Results: Although a point mutation at codon 250 was seen in one (5.8%) of 17 patients, no codon 249 mutations were found in the patient cohort. The p53 protein was overexpressed in 4 (23.5%) of 17 HCCs. PCR for HBV DNA from HCCs showed a positivity rate of 82.4% (14 of 17 specimens).

Conclusion: In HCC of this study, HBV infection was not associated with either 249 mutation or overexpression of p53, and overexpression of p53 protein seemed to be related to other than this mutation.

Original article

Evaluation of a Colorimetric Antifungal Susceptibility Test by 2,3-Diphenyl-5-Thienyl-(2)-Tetrazolium Chloride for Fluconazole in Candida Species Isolated from Clinical Specimens

Jae Hyen Kim, Jeong Hwan Shin, Eun Jung Lee, Ja Young Lee, Hye Ran Kim, Chulhun Ludgerus Chang, Jeong Nyeo Lee

Ann Clin Microbiol 2007 October, 10(2): 90-95. Published on 20 October 2007.

Background: The aims of this study were to evaluate the colorimetric antifungal susceptibility test to fluconazole using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC) for various Candida species isolated from clinical specimens and to compare the results with those of the CLSI M27-A2 standard method.

Methods: The fluconazole MICs for 204 clinical Candida isolates consisting of 100 C. albicans, 45 C. glabrata, 28 C. tropicalis, 22 C. parapsilosis, and 9 other Candida species were determined by the CLSI and STC colorimetric methods.

Results: All 204 Candida strains were grown on the growth control wells of CLSI standard plates, but 26 Candida strains (6 C. albicans and 20 C. tropicalis) were not grown on those containing STC. Therefore, those 26 Candida strains were excluded from the comparison of MICs in this report. Overall, the STC visual and spectrophotometric readings of fluconazole MICs showed 96.1% (N=171) and 89.9% (N=160) accordance with those obtained by the CLSI standard method within 2 dilutions, respectively. The STC visual reading of C. albicans showed 76.6, 92.6, and 95.8% accordance with the CLSI standard method within 1, 2, and 3 dilutions, respectively. The agreement between the two endpoint determinations of the STC colorimetric method (visual and spectrophotometric readings) was excellent, with 170 of the 178 MICs within 2 dilutions.

Conclusion: The STC colorimetric method to determine the MIC for Candida species except C. tropicalis showed high levels of agreement with CLSI method. And also, it is useful with objective and easy interpretation. 

Original article

Evaluation of Infrequent-Restriction-Site PCR for Epidemiological Typing of Candida tropicalis

Hu-Lin Han, Sook-Jin Jang, Geon Park, Jong-Hee Shin, Sung-Heui Shin, Young-Lae Moon, Dae-Soo Moon, Young-Jin Park

Ann Clin Microbiol 2007 October, 10(2): 96-101. Published on 20 October 2007.

Background: We evaluated the usefulness of a newly developed molecular typing method of infrequent restriction site polymerase chain reaction (IRS-PCR) as an epidemiological DNA fingerprinting tool for Candida tropicalis.

Methods: Thirty-two strains of C. tropicalis comprising eight sporadic strains and 24 clonal strains belonging to six clones, of which clonal type were previously confirmed by pulsed-field gel electrophoresis (PFGE), were tested by IRS-PCR to evaluate the usefulness of this technique. Twenty strains of Candida species, including C. glabrataC. krusei, C. albicans, and C. parapsilosis, were also tested to assess the ability of IRS-PCR to discriminate among species of Candida.

Results: Using the IRS-PCR assay, sporadic strains of C. tropicalis could not be differentiated from clonal strains. Most strains belonging to the same clones were classified as different IRS-PCR types or clusters, and some different sporadic strains were classified as the same IRS-PCR types. When pattern variation was examined for different strains of C. tropicalis using IRS-PCR, pairwise similarity measured by the Dice coefficient was 75.4∼100%. In contrast, pairwise similarity among isolates of five different species of Candida was 25∼69.2%. Therefore, five different species of Candida were easily differentiated.

Conclusion: The IRS-PCR typing assay appears to be an inadequate tool for the epidemiological typing of C. tropicalis, because the typing result of IRS- PCR is not comparable to that of PFGE. To our knowledge, this is the first evaluation study for IRS- PCR as an epidemiological typing tool for C. tropicalis

Original article

Surveillance for Respiratory Virus Testing Situation in Korea and Epidemiology for the Respiratory Viruses Detected in 5 University Hospitals - Report from Virus Study Group -

Jung Oak Kang, Eui Chong Kim, Kyu Man Lee, Nam Yong Lee, Chang Kyu Lee

Ann Clin Microbiol 2007 October, 10(2): 102-108. Published on 20 October 2007.

Background: Respiratory viruses (RV) are important pathogen in both children and immunocompromised hosts. Rapid diagnosis of RV is important to manage patients and to implement infection control measures. To investigate the testing situation in Korea, we performed surveillance for the 95 medical institutions. Due to the paucity of long-term, multi-center data on RV epidemiology in Korea, we analyzed data from 5 university hospitals.

Methods: Surveillance questionnaires were sent to 95 members of the Korean Society for Clinical Microbiology. The RV data from 5 university hospitals, 2001 through 2005, were collected retrospectively and analyzed for the isolation rate of each virus.

Results: Among the 63 institutions, who replied, 49% performed RV testing and 84% of the testing institutes were university hospitals. A hundred percent institutes tested for respiratory syncytial virus (RSV), whereas 81% tested for influenza virus (Flu), 74% for parainfluenza virus (PIV) and adenovirus each, 32% for rhinovirus, 23% for coronavirus, and 36% for metapneumovirus. PCR and/or culture were employed in 42% of the institutes, immunochromatography 29%, immunofluorescent assay 23%, and enzyme immunoassay 7%. Among the total 11,131 specimens received, virus was detected in 22%, ranging from 12% to 28% by hospital. The most frequently detected virus was RSV (54%) and followed by PIV (18%), Flu (15%), and adenovirus (13%). But species distributions of these viruses were quite different by hospital or by year.

Conclusion: It is necessary for more active implementation of the RV testing because only 55% of university hospitals and 17% of general hospitals performed this test. 

[in Korean]

Original article

Prevalence of Mycoplasma pneumoniae Antibodies in Healthy Residents of Jeonnam Province

Song-Mee Bae, Mi-Jung Jang, Hyun-Jae Song, Doo-Young Jeon, Sun-Seog Kweon, Yeon-Ho Kang

Ann Clin Microbiol 2007 October, 10(2): 109-113. Published on 20 October 2007.

Background: Mycoplasma pneumoniae is the most frequent cause of respiratory tract infections in school- aged children and adolescents. For appropriate use of antibiotics, diagnosis of M. pneumoniae infection in routine clinical practice has been based on serology using a single serum sample. We evaluated the seroprevalence of anti-M. pneumoniae-specific antibodies in 500 asymptomatic, healthy persons in Jeonnam Province.

Methods: Sera were collected from 500 healthy persons in Jeonnam Province. Anti-M. pneumoniae antibody titer was measured using a microparticle agglutination assay Serodia Myco II (Fujirebio, Japan) and VIRCELL IgM Mycoplasma ELISA kits (Vircell, Granada, Spain).

Results: Anti-M. pneumoniae antibody titers in 500 healthy individuals were 1:20 in 344 (68.8%), 1:40 in 16 (3.2%), 1:80 in 71 (14.2%), 1:160 in 45 (9.0%), 1:320 in 14 (2.8%), and >1:320 in 10 (2.0%). The positive rate of M. pneumoniae IgM antibodies was 3.2% (15/473). The prevalence of IgM was 10.0% in the 7∼9 years, 9.1% in the 10∼19 years, and 5.0% in the 20∼29 years old group, which was significantly higher than that in elderly people.

Conclusion: Some of healthy people showed a high anti-M. pneumoniae antibody titer (>1:160) and positive IgM, and an assessment of current infection with single serum serology has its limitation for the diagnosis of M. pneumoniae infections. 

[in Korean]

Original article

Comparison of Tn1546-like Elements in vanA Genotype Enterococcus gallinarum and E. faecalis or E. faecium

Hyukmin Lee, Eun Mi Koh, Myung Sook Kim, Jong Hwa Yum, Dongeun Yong, Wee Gyo Lee, Kyungwon Lee, Yunsop Chong

Ann Clin Microbiol 2007 October, 10(2): 114-118. Published on 20 October 2007.

Background: Enterococcus gallinarum, an organism often found in the intestine, is intrinsically resistant to low level vancomycin, but some of them are highly resistant to vancomycin due to acquisition of vanA gene. We occasionally detected both vanA carrying E. gallinarum and E. faecalis or E. faecium in the same patients, suggesting transfer of the resistance gene from the latter. In this study, the structures of Tn1546-like elements in E. gallinarum, and E. faecalis or E. faecium from the same patients were compared to determine the clinical significance of the vanA genotype E. gallinarum isolates.

Methods: Six pairs of vanA genotype E. gallinarum and E. faecalis or E. faecium were isolated at a tertiary-care hospital in Korea during 2000 to 2004. Species identification was performed by conventional methods. and the vancomycin-resistance genotypes were determined by PCR. For structural analysis of Tn1546-like elements, overlapping PCR amplification and sequencing of the internal regions were performed.

Results: All isolates were positive for vanA genes by PCR. The analysis of Tn1546-like elements showed structurally related three types of distribution of IS elements integrated: Type I had insertion of an IS1542 in the orf2-vanR intergenic region, and an IS1216V in the vanX-vanY intergenic region. Type II was similar with Type I but accompanied with the partial and complete deletions of orf1 and orf2. Type III had an IS1216V and an IS1542 in the orf2-vanR intergenic region, and an IS1216V in the vanX-vanY intergenic region. Two of the six vanA clusters in E. gallinarum isolates had structures identical to those in E. faecalis or E. faecium strains isolated from the same patients. However, in some isolate pairs, the origin of Tn1546 cannot be determined, because the structures were not identical, and colonization of multiple clones was supposed.

Conclusion: vanA clusters in some E. gallinarum, and in E. faecalis or E. faecium isolates from the same patients had an identical structure, indicating their transfer from the latter. It is assumed that vanA type E. gallinarum can act as a reservoir of vanA gene for interspecies spread.

[in Korean]

Original article

Isolation Frequency of Extended Spectrum β-Lactamase Producing Escherichia coli, Klebsiella species, and Proteus mirabilis

Young Uh, Gyu Yul Hwang, Ohgun Kwon, Kap Jun Yoon, Hyo Youl Kim

Ann Clin Microbiol 2007 October, 10(2): 119-122. Published on 20 October 2007.

Background: Accurate detection of extended spectrum β-lactamase (ESBL) is important because ESBL- producing organisms may appear susceptible to oxyimino-β-lactams in standard susceptibility tests, but are considered to be clinically resistant to these drugs. And continued monitoring of isolation trend of ESBL-producing organisms is essential for the guideline settlement of antibiotic usage and infection control program.

Methods: Disk diffusion test using the Clinical and Laboratory Standards Institute’s ESBL phenotypic confirmatory test were performed on 5,511 clinical isolates of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis during the recent six years (April 2001-March 2007). The ESBL producer was defined as an organism showing an increase in the zone diameter of ≥5 mm for either cefotaxime or ceftazidime with clavulanic acid versus that without clavulanic acid (CTC confirmatory test, CZC confirmatory test, respectively).

Results: The ESBL-positive rates were 34.8% in K. pneumoniae, 9.3% in K. oxytoca, 8.4% in E. coli, and 6.5% in P. mirabilis. Among the ESBL-positive organisms, the detection rates of ESBL CTC and CZC confirmatory tests were as follows: 91.3% vs 68.7% in K. pneumoniae, 96.3% vs 44.4% in K. oxytoca, 94.8% vs 45.4% in E. coli, and 100% vs 20% in P. mirabilis. ESBL-producing K. pneumoniae had shown a continuously increasing trend from 24.3% in 2001 to 46.4% in 2006.

Conclusion: Both of the ESBL confirmatory tests should be simultaneously tested for the accurate detection of ESBL-producing K. pneumoniae, K. oxytocaE. coli, and P. mirabilis. In addition, an active infection control approach is needed for ESBL-producing K. pneumoniae. 

[in Korean]

Original article

Evaluation of a Rapid Immunochromatographic Assay Kit for the Diagnosis of Salmonella Typhi Infection

Sun Min Lee, M.D., Young Jin Kim, M.D., Sang Hyun Hwang, M.D., Eun Yup Lee, M.D., Han Chul Son, M.D., Chulhun L. Chang, M.D.

Ann Clin Microbiol 2007 October, 10(2): 123-127. Published on 20 October 2007.

Background: Widal test, whose sensitivity and specificity are variable from region to region depending on the incidence of typhoid fever, is still in use and shows a relatively low positive predictive value in Korea. We evaluated a rapid immunochromatographic assay (ICA) kit for the rapid diagnosis of Salmonella Typhi infection.

Methods: Twenty five patients with Salmonella Typhi bacteremia were selected for the patient group. For the control group, 21 nontyphoidal salmonellosis patients, 56 non-Salmonella bacteremia patients, and 57 healthy individuals were selected for evaluating the specificity of ICA test. Each serum specimen was tested with the SD Salmonella Typhi IgG/IgM kits (Standard Diagnostics, Inc., Yongin, Korea).

Results: The ICA showed a sensitivity of 100% in Salmonella Typhi patients, and specificities of 61.9%, 82.1% and 91.2% in nontyphoidal salmonellosis patients, non-Salmonella bacteremia patients, and healthy individuals, respectively. The ICA test showed a high sensitivity but a low specificity when compared with the Widal test.

Conclusion: The ICA test by SD Salmonella Typhi IgG/IgM kit is highly sensitive, but its specificity is relatively low. The ICA test is simple, objective, and suitable for screening typhoid fever.

[in Korean]

Original article

Prevalence of Carbapenemase and Integrase Genes in Imipenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa Collected over Several Years in a University Hospital

Hye Ryong Oh, Sook Jin Jang, Feng Nan Yu, Geon Park, Xue Min Li, Sung Heui Shin, Won Yong Kim, Dae Soo Moon, Young Jin Park

Ann Clin Microbiol 2007 October, 10(2): 128-134. Published on 20 October 2007.

Background: The incidence of infections with imipenem-resistant Acinetobacter baumannii (IRAB) and Pseudomonas aeruginosa (IRPA) is increasing worldwide, and recent molecular studies indicate that the prevalence of carbapenemases is increasing in various parts of the world. However, few long-term longitudinal studies have assessed the prevalence of IRAB- and IRPA-derived carbapenemases and integrases in a hospital setting in Korea.

Methods: The carbapenemase genes (blaOXA-23blaOXA-24blaOXA-58blaIMP-1blaVIM-2blaSIM-1blaSPM-1) and integrase genes (intI1, intI2, intI3) produced by 46 IRAB strains and 51 IRPA strains collected at Chosun University Hospital between 2003 and 2006 were determined by PCR.

Results: The IRAB strains produced class 1 integrases more often than did the IRPA strains. However, the incidence increased steadily in both strains, reaching 100% in 2006. Carbapenemases of blaIMP-1 and blaVIM-2 types were found in 57% and 64% of the IRAB strains, respectively, in 2003. However, only one strain with blaVIM-2 was found in 2004 and another one with blaIMP-1 in 2005. The prevalence of carbapenemases was very low in the IRPA strains, just one strain with blaVIM-2 in 2005 and another one with blaoxa-23 in 2006. No other types of carbapenemase genes were detected in both strains. Rep-PCR of IRAB strains in 2003 showed different patterns.

Conclusion: The incidence of carbapenemase varied by year but was generally low, except in 2003. The prevalence of class 1 integrases was consistently high and increased every year. The reason for the high prevalence of carbapenemases in 2003 is still unknown, but we assumed that it was not from the spread of a clone containing either blaIMP-1 or blaVIM-2 because the strains exhibited different rep-PCR patterns.

[in Korean]

Original article

Mycobacterium tuberculosis and Nontuberculous Mycobacteria by PCR Assay

Seong Deok Lee, Hye Young Lee, Hyun Chul Kim, Soo Young Kim

Ann Clin Microbiol 2007 October, 10(2): 135-142. Published on 20 October 2007.

Background: The purpose of this study was to evaluate the usefulness of direct PCR for a rapid detection of Mycobacterium tuberculosis (MTB), the differentiation of MTB from nontuberculous mycobacteria (NTM), and the identification of NTM species in acid-fast bacilli (AFB) smear-positive specimens.

Methods: A total of 255 AFB smear-positive respiratory specimens were studied. For the differentiation of MTB from NTM, the bands of the 360 bp, which exists both in MTB and NTM, and the 190 bp, which exists only in MTB, were amplified using the one- tube nested PCR targeting regions of the rpoB gene. The two-tube nested PCR targeting 16S-23S rRNA spacer gene was done with 34 specimens that were negative by one-tube nested PCR. The specimens that were tested positive for NTMs were subsequently subjected to PCR-restriction fragment length polymorphism (PCR-RFLP) analysis based on the rpoB gene for mycobacterial species identification.

Results: Detection rate of MTB and NTM was 87% after the one-tube nested PCR. The detection range of MTB and NTM increased up to 93% after the two-tube nested PCR. The results of PCR-RFLP analysis identified those NTMs as M. avium and M. intracellulare.

Conclusion: This result seems to suggest strongly that the PCR testing especially aiming for differentiation of MTB from NTM, and identificatin of mycobacterial species using AFB smear-positive specimens would be highly importnat in clinical settings for effective treatment of patients.

[in Korean]

Original article

Drug Susceptibility and Clinical Significance of Rapidly Growing Mycobacteria Isolated from Patients with Non-Tuberculous Mycobacteriosis

Jeong Man Kim, Kyeong Hee Kim, Sun Min Lee, Kwang Won Seo, Joseph Jeong, Sung-Ryul Kim, Seon Ho Lee, Eun Yup Lee, Chulhun L. Chang

Ann Clin Microbiol 2007 October, 10(2): 143-149. Published on 20 October 2007.

Background: It is recommended that all rapidly growing mycobacteria (RGM) isolated from patients with mycobacteriosis are subjected to antimicrobial susceptibility testing. The current study was aimed to perform susceptibility test on clinical strains of RGM isolated from patients with mycobacteriosis and to determine the clinical significance of the isolates.

Methods: For 17 patients with RGM infection from 2002 to 2006 at Ulsan University Hospital, medical records were reviewed retrospectively and anti-mycobacterial susceptibility test was performed for the clinical isolates by broth microdilution method.

Results: Rates of susceptible strains of RGMs against individual drugs were as follows: amikacin 100%, cefoxitin 59%, ciprofloxacin 82%, clarithromycin 71%, doxycycline 18%, imipenem 91% (M. fortuitum), sulfamethoxazole 71%, and tobramycin 100% (M. chelonae). Ten of the 17 nontuberculous mycobacteria (NTM) patients had been treated with anti-tuberculosis drugs initially. Anti-tuberculosis drugs were continued in 3 patients and changed to other antimicrobial agents effective to NTM in 4 patients, all of whom were cured. Five of 7 NTM patients who had been treated with anti-NTM treatment were cured. All isolates from the patients treated with anti-NTM drugs were susceptible to at least one of the drugs administered.

Conclusion: Clinical isolates of RGMs showed fully susceptible to amikacin, while highly resistant to doxycycline and variable to other drugs depending on the species. 

[in Korean]

Original article

Rapid Identification of Candida albicans by ‘Spiking’ on Blood and Chocolate Agar Plates

Mi-Kyung Lee, Bo-Rae G. Park

Ann Clin Microbiol 2007 October, 10(2): 150-153. Published on 20 October 2007.

Background: Colonial morphology of Candida albicans known as ‘spiking’ on a primary isolation blood agar plate (BAP) allows rapid and presumptive identification of C. albicans. We evaluated the ‘spiking’ appearance to identify C. albicans.

Methods: A total of 144 fully identified clinical isolates of yeasts and 10 type strains of yeasts were tested. All isolates obtained from the 5% CO2 incubation on BAP and chocolate agar plate (CHOC) were macroscopically examined for the presence of an irregular margin (spiking). The germ tube test was performed by incubating test organisms in 0.5 mL of pooled human sera.

Results: The sensitivity for BAP-spiking, CHOC-spiking and germ tube test were 93.7%, 91.1%, and 98.7%, respectively. The specificity for three methods was 100%.

Conclusion: Use of the spiking identification on BAP can be useful for the economic and rapid presumptive identification of C. albicans in routine laboratories.

[in Korean]

Case report

Diagnostic Experience in the 3 Human Brucellosis Cases by the Microbiologic, Serologic and Gene Tests

Gyoung Yim Ha, Young Sil Choi, Moon Yeon Kim, Young Hyun Lee, Kyoung Seop Lee, Kyu Jam Hwang, Mi Yeon Pak

Ann Clin Microbiol 2007 October, 10(2): 154-159. Published on 20 October 2007.

Brucellosis is a zoonosis caused by Brucella species. B. melitensisB. suisB. abortus and B. canis can infect humans. Recently, as the cases of bovine brucellosis have increased every year in Korea, the cases of human brucellosis have also increased among livestock workers and veterinarians in rural areas, since the first human case was reported in 2003. Because clinical manifestations of the disease are nonspecific and may be very atypical, clinicians and laboratory persons need to be active in using diagnostic tools including polymerase chain reaction in addition to the ordinary culture and serologic tests, and taking an appropriate measure to prevent intralaboratory infection. We report herein our experience in three human brucellosis cases diagnosed by cultures, serologic tests and gene detection. 

[in Korean]

Case report

A Case of Bacteremia Caused by Arthrobacter woluwensis

Gee-Young Kim, Jin-Tae Suh, Seok-Keun Choi, Hee-Joo Lee

Ann Clin Microbiol 2007 October, 10(2): 160-163. Published on 20 October 2007.

Arthrobacter spp. are coryneform bacteria known as a soil flora and also part of normal flora of human. Since coryneform bacteria are often reported to be a cause of life-threatening diseases, and especially the human infections of Arthrobacter spp. are reported recently, it is important to identify them to the genus and species levels by additional studies including molecular tests. We report a case of bacteremia caused by Arthrobacter woluwensis, which was misidentified initially as Leifsonia aquatica by commercial kits and conventional tests, but correctly identified by 16S rRNA sequencing. 

[in Korean]

Case report

Two Cases of Vibrio fluvialis Bacteremia in Patients Undergoing Cancer Chemotherapy

Eun-Mi Koh, Chang Ki Kim, Myungsook Kim, Shin-Moo Kim, Seung-Woo Park, Hyun Cheol Chung, Dongeun Yong, Kyungwon Lee, Yunsop Chong

Ann Clin Microbiol 2007 October, 10(2): 164-167. Published on 20 October 2007.

Vibrio fluvialis is a haplophilic gram-negative bacterium normally found in coastal water and seafood and causes gastroenteritis. There have been a few reports on V. fluvialis gastroenteritis in Korea, but no previous report of isolation from blood. We isolated V. fluvialis from the blood of two patients undergoing cancer chemotherapy. 

[in Korean]

Case report

Isolation of Pasteurella dagmatis from Dog-bite Wounds

Sang Sun Hwang, Soon Deok Park, Ohgun Kwon, Young Uh, Kap Jun Yoon, Sug-Won Kim

Ann Clin Microbiol 2007 October, 10(2): 168-170. Published on 20 October 2007.

Pasteurella dagmatis is an oxidase and catalase positive, facultative anaerobic, gram-negative coccobacillus classified as a member of the family Pasteurellaceae. Pasteurella species are commonly colonizing the oropharynx of healthy domestic and wild animals including cats and dogs. These are usually pathogenic to domestic animals, but rarely to human beings. Pasteurella infection of human causes pneumonia, empyema, meningitis, peritonitis, bone and joint infection and septicemia. Recently, we experienced a case of dog-bite wounds from which Pasteurella dagmatis was isolated in a 39-year-old woman. To our knowledge, this is the first report of Pasteurella dagmatis isolated from dog-bite wounds in Korea.

[in Korean]

Research note

In vitro Susceptibility of Imipenem-resistant Pseudomonas aeruginosa against Piperacillin/tazobactam

Eui-Chong Kim

Ann Clin Microbiol 2007 October, 10(2): 171-172. Published on 20 October 2007.

Minimal inhibitory concentrations (MICs) against piperacillin/tazobactam were determined on a total of 50 clinical isolates of imipenem resistant Pseudomonas aeruginosa (IRPA). MIC50 and MIC90 were 32μg/mL and 512μg/mL, respectively. The susceptibility of IRPA against piperacillin/tazobactam was 59%. Of the 50 IRPA strains, only two were PCR positive for blaVIM and none for blaIMP

[in Korean]