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

September, 2010. Vol. 13 No. 3.

Original article

Outbreak of Swine-Origin Influenza A (H1N1); Experience of a Regional Center in Seoul during a Month, August-September 2009

Soo Jin Yoo, Choong-Hee Noh, Hyeon Mi Yoo, Won Chang Shin, Soo Jeon Choi, Baek-Nam Kim, Chang Keun Kim, Myoung-Jae Chey, Kyunam Kim, Sang-Lae Lee, Eun-Young Kuak, Bo-Moon Shin

Ann Clin Microbiol 2010 September, 13(3): 103-108. Published on 20 September 2010.

Background: The aim of this study is to clarify the epidemiology of swine-origin influenza A (H1N1) virus 2009 (S-OIV) during the first month of outbreak at one of influenza clinic in Seoul, Korea. 

Methods: We documented the epidemiologic and clinical features of S-OIV-confirmed cases who visited a university hospital in Northeastern Seoul between August 21 and September 20, 2009. Nasopharyngeal swab of patients with acute febrile respiratory illnesses were evaluated with rapid influenza antigen tests and multiplex RT-PCR for S-OIV and seasonal influenza A. 

Results: A total of 5,322 patients with acute febrile respiratory illnesses were identified at our influenza clinic for the study period. S-OIV was confirmed in 309 patients by RT-PCR. The patients ranged from 2 months to 61 years of age and 189 patients (61.2%) were teenagers. Eighty-one patients had known contact with S-OIV-confirmed patients in schools (N=61), households (N=15), and healthcare facilities (N=3). Frequent symptoms were fever (94.5%), cough (73.1%), sore throat (52.1%), and rhinorrhea (50.5%). Gastrointestinal symptoms were also present in 10 patients (4.9%). Ten patients (4.9%) required hospitalizations. Seventy patients (22.7%) could not take oseltamivir at the first visits, however, all of them recovered without complication. Rapid antigen tests showed the sensitivity of 44.4% (130/294). Patients with positive antigen tests, compared with negative antigen tests, showed higher frequencies of rhinorrhea (60.8% vs 43.3%, P=0.004) and stuffy nose (33.8% vs 20.1%, P=0.012). 

Conclusion: S-OIV infections spread predominately in school-aged children during the early accelerating phase of the outbreak. Rapid influenza antigen tests were correlated with nasal discharge and obstruction.

Original article

Comparison of Rapid Antigen Test and Real-Time Reverse Transcriptase PCR for Diagnosing Novel Swine Influenza A (H1N1)

Aerin Kwon, Jae-Seok Kim, Han-Sung Kim, Wonkeun Song, Ji-Young Park, Hyoun Chan Cho, Kyu Man Lee

Ann Clin Microbiol 2010 September, 13(3): 109-113. Published on 20 September 2010.

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 value of a positive test, and predictive value of a negative test for the rapid antigen test were 30.5%, 99.2%, 86.4% and 90.1%, respectively. Fifty-one (4.2%) patients were positive for both rapid antigen test and rRT- PCR, and 1,053 (85.7%) were negative for both rapid antigen test and rRT-PCR. A total of 124 (10.1%) patients showed a discrepancy between the two tests. Among them, 116 (9.4%) were only positive for rRT-PCR and 8 (0.7%) were only positive for the rapid antigen test. The latter 8 patients all showed negative H1/M2 results in rRT-PCR. There were significant differences in detection rates of the rapid antigen test between different H1 Ct (threshold cycle) interval groups and for different age groups (P<0.05). 

Conclusion: Although the rapid antigen test is easy to perform and provides fast results, its limits as a screening test for detection of novel swine influenza (H1N1) due to its low sensitivity compared to rRT- PCR need to be considered in practical situations.

[in Korean]

Original article

Comparison of ATB FUNGUS 2 and VITEK-2 Antifungal Susceptibility (AST-YS01) Tests for Candida Species Isolated from Blood Culture

Soon Deok Park, Young Uh, In Ho Jang, Kap Jun Yoon, Jong Hee Shin

Ann Clin Microbiol 2010 September, 13(3): 114-120. Published on 20 September 2010.

Background: The VITEK-2 yeast susceptibility test (AST-YS01; bioMerieux, Hazelwood, MO, USA) has recently been introduced as a fully automated, commercial antifungal susceptibility test system that determines MIC endpoints spectrophotometrically, thereby eliminating subjective errors. We compared the ATB FUNGUS 2 (bioMerieux) and VITEK-2 (AST- YS01) systems to the CLSI M27 method for susceptibility testing of Candida isolates. 

Methods: We tested 59 Candida species that were isolated from blood cultures at Wonju Christian Hospital between September 2008 and August 2009. We compared MIC results for amphotericin B, flucytosine, fluconazole and voriconazole using the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests to those obtained by the CLSI M27 broth microdilution method. 

Results: Within two-fold dilutions of MICs, the agreement of the ATB FUNGUS 2 and VITEK-2 (AST- YS01) tests with the CLSI method according to antifungal agents were: amphotericin B, 100% vs. 100% flucytosine, 100% vs. 100% fluconazole, 83.6% vs. 98.3% and voriconazole, 83.6% vs. 96.7%, respectively. The categorical discrepancies for fluconazole and voriconazole were 20.4% and 18.6% for ATB FUNGUS 2, and 6.8% and 0% for VITEK-2 (ASTYS01). There were no major errors for fluconazole and voriconazole in either ATB FUNGUS 2 or VITEK-2 (ASTYS01) tests. 

Conclusion: The VITEK-2 system (AST-YS01) appears to be rapid and highly correlative with the CLSI method, suggesting that it is effective for antifungal susceptibility testing for Candida species in clinical settings.

[in Korean]

Case report

Importance of Suspicion for the Identification of Mycoplasma in Wound Culture: A Case Report

Sang Mee Hwang, In Seon Yoon, Sei-Ick Joo, Jongyoun Yi, Eui-Chong Kim

Ann Clin Microbiol 2010 September, 13(3): 121-124. Published on 20 September 2010.

Genital mycoplasmas are rare in extraintestinal specimens, but can cause disseminated infections in immunocompromised patients and wound infections after surgery or injury. We report two cases of Myoplasma hominis wound infections after lung lobectomy and kidney transplantation, and a case of M. salivarium wound infection after aortic graft replacement. Mycoplasmas grew in aerobic and anaerobic cultures as tiny colonies but were not observed by gram- or acid fast stain and were confirmed by MYCOFAST EvolutioN 2 kit or 16S rRNA sequencing. These cases indicated that mycoplasmas were probably underestimated in wound infections because they were not in suspicion. We suggest that Mycoplasma should be suspected when microorganisms are not readily observable in Gram stains but can be cultured.

[in Korean]

Case report

Two Cases of Clostridium citroniae Bacteremia in Cancer Patients

Yangsoon Lee, Eun-Mi Koh, Myungsook Kim, Dongeun Yong, Seok Hoon Jeong, Kyungwon Lee, Yunsop Chong

Ann Clin Microbiol 2010 September, 13(3): 125-127. Published on 20 September 2010.

Clostridium citroniae is a novel species reclassified from C. clostridioforme. Clostridium species are obligate anaerobes and spore-forming gram-positive rods. However, C. citroniae stains gram negative and does not consistently produce spores, making it difficult to identify. We isolated C. citroniae from the blood and peritoneal fluid of one patient, and from the blood of another patient, both of whom were undergoing cancer chemotherapy.

[in Korean]

Case report

Aberrant Forms of Escherichia coli in Urine Culture

Youngeun Ma, Jang Ho Lee, Seung-Tae Lee, Chang-Seok Ki, Nam Yong Lee

Ann Clin Microbiol 2010 September, 13(3): 128-131. Published on 20 September 2010.

Bacterial morphology can be altered by various factors, including antibiotics. Unusually shaped, large, swollen organisms were observed in a urine culture obtained from a patient who had no history of antibiotic therapy. The organism was identified as Escherichia coli by the Vitek 2 system and by DNA sequencing of 16S rRNA and gyrB. The patient had no symptoms except fever, which subsided without medication. Microbiology laboratories should be aware of the potential appearance of such bacilli to avoid confusion with fungi and other naturally occurring filamentous organisms.

[in Korean]

Case report

Brodie’s Abscess Caused by Salmonella enteritica serovar Senftenberg in a Healthy Child

Nam Hee Ryoo, Jung Sook Ha, Kwang Soon Song

Ann Clin Microbiol 2010 September, 13(3): 132-134. Published on 20 September 2010.

Salmonella enteritica serovar Senftenberg is a rare pathogen in osteomyelitis, and is not usually encountered in healthy individuals. Here we report radiological and microbiological findings of a case of Brodie’s abscess caused by S. enteritica serovar Senftenberg in the left tibia of an otherwise healthy child.

Case report

Fungemia due to Exophiala dermatitidis

Eun Sun Jeong, Jong Hee Shin, Myung Geun Shin, Soon Pal Suh, Dong Wook Ryang

Ann Clin Microbiol 2010 September, 13(3): 135-139. Published on 20 September 2010.

We report a rare case of fungemia due to Exophiala (Wangiella) dermatitidis in a 4-month-old female infant who was admitted to an intensive care unit with sudden infant death syndrome (SIDS). E. dermatitidiswas repeatedly isolated from blood cultures (on the 28th and 32nd day of hospitalization) of the patient, who died on the 44th day of hospitalization. The fungus was identified by its morphological characteristics and DNA sequencing of both the D1/D2 domain and the ITS region of rDNA. To our knowledge, this is the first reported case of E. dermatitidis fungemia in Korea.

[in Korean]

Case report

A Fatal Case of Candida orthopsilosis Fungemia

Hyun Jung Choi, Jong Hee Shin, Kyung Hwa Park, Myung Geun Shin, Soon Pal Suh, Dong Wook Ryang

Ann Clin Microbiol 2010 September, 13(3): 140-143. Published on 20 September 2010.

Candida orthopsilosis is a recently described Candida species phenotypically indistinguishable from Candida parapsilosis. This new species can be identified only by using molecular methods. We describe here a fatal case of fungemia caused by C. orthopsilosis in a 75-year-old male patient who had panperitonitis after total gastrectomy with Roux-en-Y esophagojejunostomy. All 18 blood cultures obtained from admission day 16 to day 68 yielded the same Candida species. Both Vitek 2 (bioMerieux, Inc., Hazelwood, MO, USA) and API 20C (bioMerieux, Marcy-l’Etoile, France) failed to identify these isolates. However, DNA sequencing analysis of both D1/D2 domain and internal transcribed spacer region of rDNA showed 100% identity with C. orthopsilosis. The fungemia was persistent over 50 days despite of systemic antifungal therapy including fluconazole and caspofungin, and the patient expired on day 73 of his hospital stay. This represents the first reported case of fatal fungemia by C. orthopsilosis in Korea.

[in Korean]