Annals of Clinical Microbiology, The official Journal of the Korean Society of Clinical Microbiology
Volume 6 │ Issue 2 │ September 2003
Review article

Characteristics of Hepatitis B Virus(HBV) and HBV DNA Quantitative Tests

Won-Kil Lee

Ann Clin Microbiol 2003 September, 6(2): 89-96. Published on 20 September 2003.

B형 간염바이러스(Hepatitis B Virus: HBV)는 인간의 간세포에 강한 친화성을 보이고 간기능장애를 초래하는 DNA 바이러스이며, 분류학적으로는 이런 뜻을 포함하고 있는 Hepadnaviridae에 속한다. Hepadnaviridae에 속하는 바이러스로는 인간의 HBV가 원형이며 이외에도 미국산 모르모트(woodchuck hepatitis virus[WHV]), 다람쥐(ground squirrels hepatitis virus[GSHV]) 및 북경오리(duck hepatitis B virus[DHBV])에서 각각 발견되는데, 이들은 HBV와 형태가 비슷한데다 항원을 공유하고 있으며, 각각의 숙주에 대해 만성간염과 간세포성 간암을 일으킨다[1].

[in Korean]

Review article

Nosocomial Infection Control Epidemiology

Sook-Jin Jang

Ann Clin Microbiol 2003 September, 6(2): 97-102. Published on 20 September 2003.

병원감염은 입원환자들이 걸릴 수 있는 감염성합병증으로서 심한 공중보건 문제일뿐만아니라 질병이환과 사망의 주요한 원인으로서 매년 2백만건 이상의 병원감염례가 발생한다[1-3]. 미국전역의 338개 병원을 대상으로 병원감염률에 대해 포괄적으로 연구한 보고에 의하면 병원감염률이 5.7%에 달한다고 한다[1,2]. 병원 감염은 오늘날 중요한 문제이며 갈수록 그 중요성이 높아지고 있어서 병원마다 병원 감염을 관리할 수 있는 조직적인 체계를 구비하여 운영해야 할 필요성이 있다. 병원 감염을 조절할 수 있는 계획을 개발하는데 있어서 그 첫단계는 효율적인 감시체계를 통해 병원 감염을 효과적으로 인지하는것이다[4]. 감시활동을 광범위하게 정의하면 일관성있는 정의들을 사용하여 자료를 체계적으로 수집하고 분석할 뿐만 아니라 감염위험을 줄이기 위해 감시결과를 유포하거나 사용하는 것도 포함된다[5].

[in Korean]

Review article

Mechanisms of Antifungal Drug Resistance in Pathogenic Fungi

Mi Kyung Lee

Ann Clin Microbiol 2003 September, 6(2): 103-108. Published on 20 September 2003.

비록 세균감염에 비하면 일반적으로 그 빈도가 낮지만 최근 진균감염의 빈도가 꾸준히 증가하고 있으며, 최소한 다음의 두가지 측면에서 볼 때 진균감염의 증가를 의미있게 생각해볼 수 있다. 첫째, 면역기능이 약화된 환자에서의 기회감염진균증은 이들 환자에서 이환률 및 사망률 증가의 흔한 원인으로 대두되고 있다[1]. 이러한 기회감염증은 면역기능 저하를 동반하는 중증환자의 증가, human immunodeficiency virus (HIV) 감염이나 암환자에서 화학요법의 장기간 사용으로 인한 호중구 감소증 또는 장기이식 후의 면역억제치료 등에 의한 후천성면역결핍증 환자의 증가, 침습적 의료시술의 증가, 그리고 스테로이드와 광범위 항생제투여와 동시에 시행되고 있는 여러가지 의료기구와 카테터의 사용등으로 증가하고 있는 추세이다[2, 3]. 둘째, 현재 여러가지 항진균제가 개발되어 있으나, 이러한 약제들은 흔히 그들의 독성과 부작용으로 인해 사용이 제한적이어서[4], 현재 사용가능한 항진균제의 수는 비교적 적으며 화학적으로도 제한된 몇몇의 분류에만 속해있는 실정이다.

[in Korean]

Original article

Comparison of In Vitro Susceptibility between 7:1 and 4:1 Mixtures of Amoxicillin and Clavulanate against Major Clinically-isolated Bacteria

Jongyoun Yi, Jae-Kyoo Lee, Eun-Joung Lee and Eui-Chong Kim

Ann Clin Microbiol 2003 September, 6(2): 109-113. Published on 20 September 2003.

Background : Amoxicillin/clavulanate (A/C) is a combination of a broad spectrum β-lactam antibiotic amoxicillin and the potent β-lactamase inhibitor clavulanate. A/C 7:1 combination is known to be equal in its clinical efficacy and to have less gastrointestinal adverse effects compared to conventional A/C 4:1 combination. We estimated in vitro antimicrobial activities of the 7:1 combination (AMOCLA Duo) and the conventional 4:1 combination against clinical bacterial isolates known to be the major causes of acute otitis media or sinusitis.

Methods : Total 183 strains isolated from clinical specimens of patients at Seoul National University Hospital were tested for minimal inhibitory concentraion (MIC). Streptococcus pneumoniae and Haemophilus influenzae were tested by microdilution broth method and other bacterial species by agar dilution method according to the recommendations of National Committee for Clinical Laboratory Standards (NCCLS).

Results :AMOCLA Duo was compared with the 4:1 combination in respect to MIC50 , MIC90 and MIC range. For total 183 strains (30 methicillin-susceptible Staphylococcus aureus, 30 methicillin-susceptible Staphylococcus epidermidis, 25 penicillin-susceptible S. pneumoniae, 42 penicillin-resistant S. pneumoniae, 33 H. influenzae and 23 Moraxella catarrhalis), mean MICs did not show statistically significant difference between the 2 combinations but they did for H. influenzae and M. catarrhalis.

Conclusions : As for the total test strains, in vitro antimicrobial activity of AMOCLA Duo was equal to that of the conventional 4:1 combination. For each species, H. influenzae and M. catarrhalis showed significant difference between mean MICs of the 2 combinations but other species did not. We do not suppose, however, that in case of H. influenzae this difference is of practical and clinical significance according to the NCCLS interpretive criteria for MIC. Although M. catarrhalis showed statistically very significant difference of MICs, this difference can be clinically solved due to the higher dose of amoxicillin in AMOCLA Duo.

[in Korean]

Original article

Molecular Characterization of Vancomycin-Resistant Enterococci Isolated from Poultry in Korea

Ji Young Huh, Sun Min Lee, Suck Ho Lee, Wee Gyo Lee, Dongeun Yong, Kyungwon Lee, Wan Shik Shin and Dong Gun Lee

Ann Clin Microbiol 2003 September, 6(2): 114-118. Published on 20 September 2003.

Background : Vancomycin-resistant enterococci (VRE) have been increasingly isolated worldwide as a nosocomial pathogen. In Korea, because avoparcin has been used as a growth promoter in animal feed, vanA-containing enterococci have been found in animals. The aim of this study is to understand the epidimiology of VRE isolated from chicken of diverse geographic areas. 

Methods : Thirty eight isolates of VanA VRE from chicken of diverse geographic areas were investigated. Multiplex PCR was used to confirm the genotype of VRE. Long PCR and restriction fragment length polymorphism (long PCR-RFLP) were performed to analyze the structure of Tn1546. If the RFLP pattern was different from the prototype, PCR amplification of internal regions of Tn1546 and subsequent sequencing analysis was performed. 

Results : All 38 isolates harbored vanA gene and divided into 3 types by long PCR-RFLP. Thirty five isolates (92%) were classified as type I. Two isolates and one isolate were belonging to type II and type III, respectively. Type II revealed an insertion of IS 1216V in vanX-vanY intergenic region. IS element integrated type III did not match any previously reqorted seguence.

Conclusion : Structural analysis of vanA gene cluster from chicken revealed that the majority of isolates (type I) have indistinguishable structure to E. fecium BM4147. This results indicated horizontal spread of resistance gene among isolates from chicken. Genetic rearrangement of Tn1546 was infrequently detected in Korea.

[in Korean]

Original article

Molecular Characterization of vanA-containing Enterococcus faecium Isolated from a Teaching Hospital

Wee Gyo Lee, Suck Ho Lee, Sun Min Lee, Ji Young Huh, Dongeun Yong, Kyungwon Lee, Wan Shik Shin and Dong Gun Lee

Ann Clin Microbiol 2003 September, 6(2): 119-125. Published on 20 September 2003.

Background : The widespread dissemination of Tn1546 has been attributed to transposition into plasmid or transferable elements. The transposition has been achieved through the activity of insertion sequences. Genetic diversity in Tn1546 includes integration of IS elements such as IS1216V, IS1251, IS1476 and IS1542. We investigated molecular typing and the distribution of insertion sequences in vanA-containing Enterococcus faecium isolated from patients in a teaching hospital.

Methods : Sixteen strains of vanA-containing E. faecium isolated from Ajou university hospital were analyzed. PCR amplification of internal regions of Tn1546 was performed and PCR amplicons were directly sequenced on both DNA strands by the dideoxy termination method.

Results : For all 16 isolates, IS1216V sequences were located within Tn1546. IS1542 sequences were detected in the genome of 9 isolates. One isolate contained IS1216V in the vanS intragenic region. The structural analysis of Tn1546 in VRE isolates produced three different groups by the presence of the insertion sequences. Group I was characterized by deletions of orf1 and orf2 and IS1216V insertion in the vanXY intergenic region. Group II represented IS1542 in the orf2-vanR and IS1216V in the vanXY intergenic region with deletion of orf1 region. Group III represented IS1542 in the orf2-vanR and IS1216V in the vanXY intergenic region without any deletion.

Conclusions : Most of Korean isolates contained IS1216V and IS1542 sequences. Transposon typing of isolates in this study revealed a similarity to the European’s. The identification of insertion sequence within vanA gene cluster can be a useful tool in epidemiological investigations.

[in Korean]

Original article

Genomic analysis of Vibrio vulnificus by Infrequent Restriction Site-Polymerase Chain Reaction

Eun Jung Baek, Jung Oak Kang and Tae Yeal Choi

Ann Clin Microbiol 2003 September, 6(2): 126-131. Published on 20 September 2003.

Background:Vibrio vulnificus sepsis is one of the notifiable disease(Class 3) in Korea. It is usually acquired through the consumption of raw or undercooked seafood in summer. We studied the clinical findings of V. vulnificus septicemia and the genomic patterns of V. vulnificus isolates. 

Methods:Seven patients with V. vulnificus septicemia were admitted to Hanyang University hospital from 1998 to 2002. We analysed the clinical findings and the genomic patterns by infrequent restriction site-polymerase chain reaction(IRS-PCR). 

Results:All patients were over forty years old, and five were male. The patients had underlying diseases;five with liver cirrhosis, two with DM, and four patients with heavy alcoholism. Five of seven patients had history of ingesting raw fish and four had tissue necrosis with bullae or vesicles in their extremities. Four patients who died showed disseminated intravascular coagulation symptoms. We applied IRS-PCR to 6 isolates from blood and 2 isolates from wound. The six isolates from blood showed various genomic patterns that were all different from one another, while the two isolates from wound showed IRS-PCR patterns that were identical to the blood isolates of the same patients. 

Conclusions:The genomic patterns of IRS-PCR are quite different in 6 cases of V. vulnificus isolates in Korea.

[in Korean]

Original article

Risk Factors for Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Children with Urinary Tract Infections

Hee Won Moon, Mi Ae Lee and Seung Joo Lee

Ann Clin Microbiol 2003 September, 6(2): 132-138. Published on 20 September 2003.

Background:Recently our institution noted a marked increase in the number of ExtendedSpectrum β-Lactamase(ESBL)-producing Escherichia coli isolated from children with urinary tract infections (UTI). The purpose of this study was to investigate frequency, risk factors and outcomes for pediatric UTI due to ESBL-producing E. coli.

Methods:We analyzed 27 children with UTI due to ESBL-producing E. coli (cases) and 27 children with UTI due to non-ESBL-producing E. coli (controls) in Ewha Womans University Hospital from July to December 2001.

Results:Of the total 434 E. coli isolates from urine, 32 (7.4%) produced ESBL and the prevalence of UTI due to ESBL-producing E. coli was higher in children (15.2%) than in adults (2.0%). Case patients had higher resistances to ampicillin/sulbactam, aztreonam, cefazolin, ceftriaxone, gentamicin, tobramycin, TMP-SXT and piperacillin/tazobactam than controls. No significant differences were noted in resistance to amikacin, ampicillin, cefoxitin, ciprofloxacin and imipenem (P>0.05). Case patients were younger and more frequently male than control patients. No significant differences were noted in prior UTI, prior antibiotic use, genitourinary abnormality, vesicoureteral reflux, urinary catheter, pyelonephritis or underlying diseases (P>0.05). No significant difference in cure rate was noted between both groups, but case patients had a significantly higher relapse (11/27) than control patients (1/27) (P<0.05).

Conclusions:ESBL-producing E. coli may be a causative agent of UTI in children without any specific risk factors. To eradicate ESBL-producing strains, new guidelines of detection and antibiotic therapy for pediatric UTI may be necessary through more evaluation.

[in Korean]

Original article

Evaluation of Diagnostic Utility of Intradermal Test for the Diagnosis of Clonorchis sinensis Infestation

Jae-Cheol Choi, Seung-Hwan Oh, Hae Jin Jeong, Junghwan Shin, Ki Hyung Park, Eun Yup Lee, and Chulhun Ludgerus Chang

Ann Clin Microbiol 2003 September, 6(2): 139-143. Published on 20 September 2003.

Background :The intradermal test for the screening of Clonorchis sinensis is difficult to interpret because the sensitivity and persistence rates of reactions after treatment are not well known.

Methods : Stool egg examinations and intradermal tests for C. sinensis and Paragonimus westermani were performed for 1,207 persons who lived in endemic areas of C. sinensis infestation, and epidemiologic data were also surveyed.

Results :The infestation rate of C. sinensis was 12% (male 14%, female 9%). It was higher in Southeastern area of Gyungsang Namdo Province and Ulsan (22%) than in Busan (10%), whereas much higher in Gangseo/Buk/Sasang (28%) than in other areas of Busan. The performance of C. sinensis intradermal test was as belows; sensitivity 45%, specificity 80.8%, positive predictive value 24%, negative predictive value 92%, and diagnostic efficiency 77%. Positive C. sinensis intradermal reaction persisted for longer than 40 years after treatment of C. sinensis infestation in at least 30% of patients. C. sinensis intradermal reaction turned to be positive within 4 months after intake of raw fish in more than half the patients.

Conclusion :The infestation rate of C. sinensis was still very high in inhabitants around Nakdong River, an endemic area. We think that C. sinensis intradermal test is inadequate to diagnose current clonorchiasis.

[in Korean]

Original article

Presumptive Identification of Candida Species Using Candida ID

Hwi Rin Kim, and Mi Ae Lee

Ann Clin Microbiol 2003 September, 6(2): 144-148. Published on 20 September 2003.

Background:Candida ID is introduced as a new chromogenic medium that allows presumptive identification of Candida species. We evaluated this medium to identify Candida spp. isolated from clinical specimens.

Methods:A total of 200 yeast isolates from clinical specimens in Ewha Womans University Mokdong Hospital, from April 2001 to August 2001 were identified by using the Vitek YBC (Hazelwood, Mo., USA). The results were compared with those by Candida ID (bioMeriux, Marcy l’Etoile, France).

Results:Candida ID correctly identified 98.0% of Candida spp. including 100% of C. albicans and 98.9% of C. tropicalis compared with the Vitek YBC. Among 84 strains showing blue colored colony on Candida ID, 82 strains (98%) were correctly identified as C. albicans but 2 strains were identified as C. glabrata and C. guilliermondii by the Vitek YBC. Among 92 strains showing pink colored colony, 90 strains (98%) were identified as C. tropicalis, and 2 strains were identified as C. guilliermondii and C. lusitaniae by the vitek YBC.

Conclusions:Candida ID provides a more rapid and easier presumptive identification of major Candida spp. isolated from clinical specimens.

[in Korean]

Original article

Prevalence & Diversity of Extended-spectrum β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae Isolates in Korea

Seong Geun Hong, Sunjoo Kim, Seok Hoon Jeong, Chulhun L. Chang, Sung Ran Cho, Ji Young Ahn, Jong Hee Shin, Hye Soo Lee, Won Keun Song, Young Uh, Jong Hwa Yum, Dongeun Yong, Kyungwon Lee, Yunsop Chong

Ann Clin Microbiol 2003 September, 6(2): 149-155. Published on 20 September 2003.

Background:Increase in extended-spectrum β-lactamase(ESBL)-producing Escherichia coli and Klebsiella pneumoniae have been reported in Korea. The aim of this study was to determine the nationwide prevalence of ESBL-producing E. coli and K. pneumoniae, and to investigate the types of ESBLs.

Methods:A total of 2,221 E. coli and 1,128 K. pneumoniae consecutive isolates were yearly collected from 12 hospitals in 1999 and 2000. ESBL production was performed by National Committee for Clinical Laboratory Standards methods and double synergy tests. The type of ESBL was determined by polymerase chain reaction (PCR), isoelectric focusing, and nucleotide sequence analysis.

Results:ESBL-producing E. coli and K. pneumoniae isolates were detected from all 12 hospitals participated. The proportion of ESBL-producers was 9.1%(2.0-19.6%) of the E. coli and 29.2% (10.0-60.8%) of the K. pneumoniae isolates. Among the 22 isolates sequenced, SHV-12 was found in six isolates, SHV-2a in three isolates, TEM-52 in five isolates, TEM-106 in three isolates, and each of TEM-15, TEM-20, TEM-43, and TEM-107 in one isolate. CTX-M-14 was also found in one isolate.

Conclusion:ESBL-producing E. coli and K. pneumoniae are widespred to all levels of Korean hospitals. The most common types of ESBLs in Korea are SHV-12, SHV-2a, and TEM-52. In addition, we also identified new TEM-derived ESBLs.

[in Korean]

Original article

Evaluation of Asan Helicobacter Test for Diagnosis of Helicobacter pylori Infection

Jongwook Lee, Pum Soo Kim, Kyungwon Lee, Jae Hag Lee, Jae Kyoung Lee, Chang Hoon Lee

Ann Clin Microbiol 2003 September, 6(2): 156-159. Published on 20 September 2003.

Background:Helicobacter pylori is the single most common pathogen that causes chronic bacterial infection in human. The authors designed a new type of urease detection method (Asan Helicobacter test) that can be used for rapid early detection of H. pylori as well as a transport medium. This medium has a strong acidity with a minimal concentration of urea for the purpose of the detection of H. pylori. The current study was to evaluate the bacteriological and clinical usefulness of this medium.

Method:252 antral biopsies from patients underwent upper gastrointestinal endoscopies in Inha University Hospital were inserted Asan Helicobacter Test and CLO test. 37 antral biopsies from patients underwent upper gastrointestinal endoscopies in Konyang University Hospital were inserted Asan Helicobacter Test. Biopsies were cultured on nonselective media only.

Result:The sensitivity and specificity of the Asan Helicobacter test were comparable with the CLO test (88.0% and 94.0%, respectively), and the results agreed in 99.2% of 252 cases with the CLO test. With this transport medium, all 23 specimens that showed positive reaction among 37 patients yielded satisfactory isolation of H. pylori.

Conclusion:These findings suggest that the reagent in the kit inhibit the growth of microbial contaminant due to low pH and do not suppresses growth of H. pylori due to low concentration of urea. This kit may be used as a transport medium as well as a rapid urease test for H. pylori.

[in Korean]

Case report

The First Outbreak of Botulism in Korea

Gyung Tae Chung, Do Hyun Kang, Cheon Kwon Yoo, Jong Hyun Choi and Won Keun Seong

Ann Clin Microbiol 2003 September, 6(2): 160-163. Published on 20 September 2003.

Botulism is a rare neuroparalytic disease caused by neurotoxins of Clostridium species. A tenyear-old girl and her mother were admitted to a hospital with symptoms of progressive dizziness, blurred vision, slurred speech, constipation and difficulty in swallowing. These characteristic manifestations and clinical course prompted an examination of the possibility of botulism. Mouse bioassay performed with mother’s stool demonstrated type A botulinum toxin and culture of the mother’s stool was positive for Clostridium botulinum type A. This is the first case of botulism in Korea.

[in Korean]

Case report

A Case of Small Colony Variants (SCVs) of Staphylococcus aureus from Sputum of a Patient with Chronic Renal Failure

Hye Soo Lee, Yong Kohn Cho, Dal Sik Kim, and Sam Im Choi

Ann Clin Microbiol 2003 September, 6(2): 164-167. Published on 20 September 2003.

Recently, small colony variants (SCVs) of Staphylococcus aureus causing fatal infections are increasing, but rarely reported in Korea. S. aureus, SCVs are slow growing subpopulation that cause persistent and relapsing infections. S. aureus, SCVs are frequently auxotrophic for hemin, menadione, and CO2, and are often disrupted in their electron transport activity. With S. aureus, SCVs virulence is altered by a decrease in α-toxin production and susceptibility to various antibiotics, allowing their intracellular survival. We isolated S. aureus, SCVs from the sputum of a 67 year old male with pneumonia, chronic renal failure with hemodialysis and preventive antibiotic therapy. Because S. aureus, SCVs are easily missed or misdiagnosed as normal flora in routine culture due to their atypical growth behavior and biochemical reaction, the correct identification is very important, especially when no bacteria or unusual bacteria are found in patients with persistent or relapsing infections with long term antibiotic therapy.

[in Korean]

Case report

A Case of Saccharomyces cerevisiae Isolated from Stool of a Patient Administered Yeast Biotherapeutic Agent

Yun Hee Kim, Mi Ae Lee and Ki Sook Hong

Ann Clin Microbiol 2003 September, 6(2): 168-171. Published on 20 September 2003.

A particular strain of Saccharomyces cerevisiae, Hansen CBS 5926 (syn. S. boulardii), is commonly used as biotherapeutic agent for the prevention and treatment of antibiotic associated diarrhea. Recently, cases of fungemia with S. cerevisiae have increased especially in immunosuppressed or critically ill patients treated with S. boulardii. And S. boulardii administered can simply pass into stool and be isolated as S. cerevisiae. In cases of S. cerevisiae isolated from clinical specimens, it should be required to confirm the relatedness with administration of biotherapeutic agent composed of S. boulardii. A 61-year-old woman who had persistent urinary tract infection by C. tropicalis, developed absolute neutopenia, fever and watery diarrhea and treated with Bioflor composed of S. boulardii, amikacin, ceftriaxone, metronidazole and fluconazole during 3rd chemotherapy against bladder cancer with liver metastasis. On KOH smear of stool specimen, yeasts were observed and the yeasts were identified as S. cerevisiae. She was diagnosed as fungal enterocolitis and sepsis and treated with amphotericin B, but considering her clinical course, S. cerevisiae was presumed not to be a pathogen, but to be a simple passage of S. boulardii administered from intestine. We report a case of S. cerevisiae isolated from stool specimen of a patient administered Bioflor with literatures review.

[in Korean]

Case report

A Case of Haemophilus aphrophilus Endocarditis

Choong Hwan Cha, Hee Bong Shin, Seongsoo Jang, Min Kyung Kim, Yang Soo Kim, Jae Kawn Song and Mi-Na Kim

Ann Clin Microbiol 2003 September, 6(2): 172-176. Published on 20 September 2003.

Haemophilus aphrophilus is a facultatively anaerobic gram-negative bacillus and require 5 to 10 % to grow optimally. H. aphrophilus is differentiated from other members of Haemophilus species by no requirement of X or V factor. This organism is found as the normal flora in upper respiratory tract but a member of the HACEK group that cause native valve endocarditis. Since the first endocarditis of H. aphrophilus was reported at 1985 in Korea, we reported the second case. 

A 35-year-old male patient was admitted to Asan Medical Center because of fever for 15 days and altered mentality developed 2 days ago. His echocardiography revealed a mitral valve regurgitation with a hypermobile vegetation and multiple septic emboli were also found in the brain MRI. Three sets of blood cultures were taken on the day of admission, all of which grew pleomorphic, gram-negative bacilli at incubation day 1. Catalase and oxidase test was negative and Vitek NHI card (bioMerieux Vitek, Inc., Hazelwood Mo., USA) identified the organisms to H. aphrophilus 50%/H. paraphrophilus 49% (Bionumber 257310). It was finally identified to H. aphrophilus with requirement tests of X or V factors; it required neither X nor V factor. This H. aphrophilus strain was negative in lactamase and was susceptible to ampicillin, gentamicin, cefuroxime, imipenem, ciprofloxacin, aztreonam, azithromycin, rifampin, and trimethoprim/sulfamethoxazole. This patient was successfully treated with ampicillin and gentamicin after mitral valve replacement under diagnosis of H. aphrophilus endocarditis.

[in Korean]

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