EUCAST v.12.0 개정 사항

송새암 대한임상미생물학회 2022 Annals of clinical microbiology Vol.25 No.3

Clinical and Laboratory Standards Institute and European Committee on AntimicrobialSusceptibility Testing (EUCAST) clinical breakpoint tables are commonly used as guidelines forthe interpretation of antimicrobial susceptibility testing results. These are updated annuallyto reflect new and revised antimicrobial susceptibility breakpoints. EUCAST v.12.0, whichwas published in January 2022, presents updated meropenem-vaborbactam breakpointsfor Enterobacterales and Pseudomonas aeruginosa . It also suggests new breakpoints ofsusceptibility to various antibiotics for Vibrio spp. Flow charts were updated for Streptococcuspneumoniae and Haemophilus influenzae, and the breakpoints for anaerobic bacteria weredivided according to each species. Furthermore, recommendations were made for caseswithout antimicrobial susceptibility testing breakpoints and links to several rationale andguidance documents were provided for technical convenience.

무산소성 혈액배양병 사용의 임상적 유용성

송새암,김지현,신정환,김시현,이남용,김미나,김선주 대한임상미생물학회 2014 Annals of clinical microbiology Vol.17 No.2

배경: 균증과 진균증을 진단하기 한 액 배양은 산소병과 무산소성병을 한 세트로 시행하는 것이 권장되지만 무산소성병을 선택으로 사용하기도 한다. 이 연구에서는 무산소성병 사용의 유용성을 평가하고자 하다. 방법: 4개의 학병원에서 성인을 상으로 시행한 액배양에서 양성을 보인 총 9,028을 분석하다. 수집된 자료로 균종별로 각각 산소성병에서만 증식한 경우, 무산소성병에서만 증식한 경우, 두 가지 모두 증식한 경우로 나어 분석하 다. 결과: 9,028개의 액배양 양성 가운데 산소성병에서만 자란 경우는 3,239건(35.9%), 무산소성병에서만 자란 것은 1,543 건(17.1%), 두 가지 모두에서 자란 경우는 4,246건(47.0%)이었다. 무산소성병에서만 배양된 균의 분포는 통성 무산소성 세균이 81.4%, 산소성 세균이 8.5%, 무산소성 세균이 2.0%고, 진균이 8.1%다. 결론: 균증 환자에서 통성 무산소성 세균과 진균이 무산소성병에서만 증식하는 경우가 상당수 있으므로 액배양 시 산소성병과 무산소성병 세트 사용이 필수일 것으로 생각된다. 무산소성병에서는 무산소성 균보다 오히려 산소성 균이나 진균이 자주 분리되었다. [Ann Clin Microbiol 2014;17:35-41]

Rh 항원 부적합 적혈구 수혈에 의한 동종면역 발생의 확인

송새암,오승환,유신애,전경란,이정녀 대한수혈학회 2020 大韓輸血學會誌 Vol.31 No.3

The rhesus (Rh) blood group system is one of the most important systems in transfusion medicine. Rh alloantibodies can cause hemolytic transfusion reactions and difficulties in finding compatible blood. On the other hand, the phenotypic test and pre-transfusion compatibilization for RhCE antigens have not been routinely performed in most clinical laboratories. This study examined the occurrence of Rh alloimmunization, including C, c, E, and e antigens, after Rh incompatible red cell transfusion during a specific period. From November 2016 to December 2017, clinical and laboratory information of transfused patients was collected; this included the transfusion history and Rh phenotypes of the patients and transfused red blood cell (RBC) products. Of 3,623 patients who received red cell transfusion, 99 (2.8%) revealed unexpected antibodies. Among them, 48 patients (48.5%) had alloantibodies to the Rh-system antigen, including the anti-D antibody. Based on the transfusion history and Rh phenotypes of patients and transfused packed RBCs, 11 patients (11.1%) were assumed to develop Rh alloantibodies after discrepant Rh phenotype red cell transfusion. A considerable proportion of unexpected antibodies was caused by the exposure of Rh mismatched red cells. Therefore, extended Rh antigen matching, including the C, c, E, and e, is needed to prevent alloimmunization. (Korean J Blood Transfus 2020;31:247-253)

효소반응단계에서 소실되는 항-Jkb에 의한 용혈수혈반응 1예

송새암,오승환,이자영,성성경,신정환,김혜란,전경란,이정녀 대한수혈학회 2016 大韓輸血學會誌 Vol.27 No.1

We report a case of an intravascular hemolytic reaction attributable to anti-Jkb antibodies that were not detected using an enzyme phase antibody identification test. A 61-year-old male who had received two units of red blood cells was admitted to the emergency room because his urine was dark. LISS/Coombs gel column agglutination tests suggested the presence of anti-Jkb and anti-E antibodies. However, his serum was negative for the Jkb antigen when an enzyme phase test was performed. A positive reaction was evident, however, when EDTA-treated plasma was tested; this excluded any possible complement-mediated reaction. The patient was diagnosed with an intravascular hemolytic transfusion reaction, caused by anti-Jkb, and was later discharged without specific complications after receiving antigen-negative blood transfusions. 저자들은 효소법에서 항체 반응이 소실된 항-Jkb 의 사례와 이에 의한 혈관내 용혈성 수혈 부작용1례를 경험하였기에 이를 보고하고자 한다. 환자는 61세 남자 환자로 2단위 적혈구 수혈 후 적갈색 소변을 주소로 내원하였다. LISS/Coombs card 법을 이용한 비예기항체 검사에서 항-E와 항-Jkb 가 의심되었으나, 효소법에서 Jkb 항원 적혈구와의 항체반응은 음성이었다. 이에 보체결합에 의한 억제반응으로 생각되어 EDTA 혈장을 이용하여 반응시킨 결과 항-Jkb에 의한 용혈성 수혈부작용을 진단할 수 있었고, 환자는 해당 항원음성 적혈구제제를 수혈하고 특이적인 합병증 없이 퇴원하였다.

유전구형적혈구증 환자에서 Parvovirus B19에 의한 골수무형성위기 이후 발생한 자가면역용혈빈혈 1예

송새암,이민영,김시현,이자영,오승환,김혜란,전경란,이정녀,신정환 대한진단검사의학회 2012 Laboratory Medicine Online Vol.2 No.3

유전구형적혈구증은 적혈구막의 세포골격층을 구성하는 단백질의 결핍으로 인해 구형적혈구가 생겨 지속적으로 용혈이 일어나는 유전질환이다. 본 질환의 경과 중 parvovirus B19 감염으로 인한골수무형성위기를 동반할 수 있다. Parvovirus B19 감염은 전염성홍반과 관절염 등의 질환뿐 아니라 자가면역용혈빈혈을 포함한 다양한 자가면역질환도 유발하는 것으로 알려져 있다. 이에 본 저자들은 유전구형적혈구증을 가진 11세 남아에서 parvovirus B19 감염에 의한 골수무형성위기 3개월 이후 회복기에서 parvovirus B19IgM이 지속적으로 검출되면서 자가면역용혈빈혈이 추가로 동반된드문 1예를 경험하여 이를 문헌 검토와 함께 보고하고자 한다 Hereditary spherocytosis (HS) is a genetic disorder characterized by the production and destruction of spherocytes due to a deficiency of red cell membrane cytoskeletal proteins, resulting in the clinical presentation of chronic hemolytic anemia. This disease can be accompanied by an aplastic crisis due to parvovirus B19 infection. Parvovirus B19 infection causes diseases such as erythema infectiosum and arthritis, and can also trigger various autoimmune diseases, including autoimmune hemolytic anemia (AIHA). Here, we report a rare case of AIHA developing 3 months after an aplastic crisis due to parvovirus B19 infection in an 11-year-old boy with HS and provide the relevant literature review.

비예기항체 선별검사에서 항-Lua의 검출: 증례보고 및 문헌고찰

송새암,오승환,박태성,손혜수,성성경,이자영,전경란,신정환,김혜란,이정녀 대한수혈학회 2012 大韓輸血學會誌 Vol.23 No.2

Lutheran a antigen (Lua) is detected in 6 to 8% of Caucasians and Africans. In Korean and other Asian populations, it is very rare or nearly absent. Therefore, although Lua has a considerable immunizing capacity, sensitization to Lua is a rare event. Here we report on a rare case of anti-Lua in a 70 year-old female patient with Lu (a−/b+) phenotype and review the relevant literature. Due to the paucity of Lua positive panel cells in antibody screening and identification tests, detection of this rare antibody to Lua antigen is not feasible. Therefore, we should keep in mind the possibility of the misleading false negative result in detection of antibody to this low incidence antigen.

결핵균 검사에 관한 전국 다기관 실태조사

송새암,김시현,김창기,성흥섭,김선주,장철훈,신정환 대한임상미생물학회 2015 Annals of clinical microbiology Vol.18 No.3

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 quality control for M. tuberculosis using a nationwide survey in the Republic of Korea. Methods: We constructed a questionnaire composed of four subseries with 42 items. We e-mailed this survey to members of the Korean Society of Clinical Microbiology from April to September 2014 and analyzed the replies. Results: Employees at a total of 65 hospital laboratories and 5 commercial laboratories participated in the survey. AFB staining was reportedly performed in all 70 institutions, and fluorescent staining was used as the primary detection method in 59 (84.3%) laboratories. Solid and liquid culture methods for Mycobacterium were performed at 62 (88.6%) and 59 (84.3%) laboratories, respectively. There were 57 laboratories (90.5%) that identified strains growing on primary culture media using a rapid antigen kit or molecular method. The mean values of positive and contamination rates for solid culture media were 8.2% (range 3.7-19.9%) and 4.0% (0.4-8.4%), respectively. In liquid culture, the mean values of positive and contamination rates were 11.5% (4.8-22.3%) and 6.8% (0.3-18.7%), respectively. Conclusion: There have been significant changes and improvements in overall mycobacterial testing, especially in the numbers of laboratories using fluorescent staining, liquid culture, and identification of M. tuberculosis cultured media compared with previous surveys in Korea. (Ann Clin Microbiol 2015;18:-75)

자동혈구분석기 Sysmex XN-2000의 성능 및 Low WBC Mode를 이용한 백혈구 감별계산 정확성 평가

이자영,송새암,오승환,신정환,김혜란,전경란,이정녀 대한진단검사의학회 2015 Laboratory Medicine Online Vol.5 No.4

배경: XN- series (Sysmex, Japan)는 Sysmex사의 최신 혈액분석기로 새로운 채널 도입을 통해 낮은 세포수 범위에서 백혈구 감별계산 및 혈소판 수 계산의 정확성을 향상시켰다. 저자들은 XN-2000의 분석 성능 및 low white blood cell (WBC) mode를 평가하고자 하였다. 방법: 상기 장비의 정밀도, 직선성 및 잔효를 평가하였다. 200건의 정상인 및 환자 검체를 이용하여 XN-2000의 전혈구계산, 망상적혈구 계산 및 백혈구 감별계산을 XE-2100 (Sysmex)과 비교하여 상관성을 분석하였다. 백혈구 수 1.5×109/L 미만인 80검체를 대상으로 low WBC mode를 이용한 백혈구 감별계산 결과를 참고방법인 수기법과 비교하여 평가하였다. 결과: 정밀도 분석에서 변이계수는 대부분 전혈구계산 지표에서 <5%, 백혈구 감별계산에서 <10%였다. XN-2000의 모든 분석 결과는 XE-2100 결과와 우수한 상관성을 보였다. 상관계수(r)는 평균적혈구혈색소농도, 평균혈소판용적, 혈소판분포폭을 제외한 전혈구계산 지표에서 >0.9800이었고, 단구 및 호염기구를 제외한 백혈구 감별계산에서 >0.9900이었다. Low WBC mode는 백혈구 수 0.1-1.5×109/L 범위에서 호중구 및 림프구의 감별계산결과가 수기법과 r>0.9300를 보여 정확한 백혈구 감별계산 결과를 제공하는 것을 확인하였다. 결론: XN-2000은 우수한 분석수행능을 보이고, 기존 모델인 XE-2100과 우수한 상관성을 보였다. XN-2000의 low WBC mode는 백혈구 수 0.1-1.5×109/L 일 때 정확한 백혈구 감별계산 결과보고가 가능하므로 수기법을 통한 슬라이드 검토시간을 줄여줄 수 있다. Background: The XN-series (Sysmex, Japan) is the new hematology analyzer from Sysmex, with new channels to improve the accuracy of differential leukocyte count and platelet count in the low cell count range. We evaluated the analytical performance and low white blood cell (WBC) mode of the XN-2000. Methods: Precision, linearity, and carryover were evaluated for the analyzer. We analyzed the accordance of complete blood count (CBC), reticulocyte count, and differential leukocyte count between the XN-2000 and XE-2100 (Sysmex), using 200 samples from normal controls and patients. For 80 samples with a WBC count <1.5×109 cells/L, the low WBC mode was evaluated by comparing the automated count with a manual differential count as the reference. Results: The coefficients of variation of precision were <5% for most CBC parameters and <10% for differential leukocyte count. All results obtained with the XN-2000 showed good correlation with those obtained with the XE-2100. The correlation coefficients (r) were >0.9800 for all CBC parameters except mean corpuscular hemoglobin concentration, mean platelet volume, and platelet distribution width, and >0.9900 for differential leukocyte count except monocytes and basophils. The low WBC mode provided accurate counts for neutrophils and lymphocytes, with r >0.9300 for samples with a WBC count of 0.1-1.5×109 cells/L. Conclusions: The XN-2000 showed good analytical performance and correlation with the existing model, the XE-2100. The XN-2000 provided accurate results for differential leukocyte count in samples with a WBC count of 0.1-1.5×109 cells/L, and reduced manual slide reviews.

부산 및 경남 4개 대학병원에서 분리된 폐렴알균의 분포 및 항균제 내성

김시현,송새암,이종윤,송두열,장철훈,박동철,엄상화,김혜란,신정환 대한임상미생물학회 2016 Annals of clinical microbiology Vol.19 No.2

Background: Streptococcus pneumoniae is the most common human pathogen causing community-acquired pneumonia. There is little information on the recent antimicrobial susceptibility patterns of S. pneumoniae in Busan and Gyeongnam of Korea. The aim of this study was to investigate the distribution and antimicrobial resistance of S. pneumoniae at 4 university hospitals in Busan and Gyeongnam. Methods: We collected and analyzed the antimicrobial susceptibility results of 850 S. pneumoniae strains isolated from regional 4 university hospitals during the last 2 years from July 2013 through June 2015. Results: Among 850 S. pneumoniae strains, 635 strains were isolated from respiratory specimens, followed by blood (N=121), CSF (N=13), and others (N=81). Antimicrobial susceptibility rates to penicillin, cefotaxime and ceftriaxone were 79.4%, 76.6% and 83.6%, respectively. The resistant rates to erythromycin and clindamycin were 80.9% and 68.2%, respectively. The resistant rates to levofloxacin were 9.2%. There were some differences in resistant rates by age groups, years, and specimen types. Conclusion: We found the changes of antimicrobial resistance of S. pneumoniae during the last 2 years. It is necessary to monitor the antimicrobial susceptibility of S. pneumoniae regularly for empirical therapy and for early detection of the changes of resistance.

한국인에서 O 형 대립유전자의 분자유전학 및 혈청학적 분석

이자영,송새암,오승환 대한수혈학회 2019 大韓輸血學會誌 Vol.30 No.2

Background: The recent expansion of knowledge about various ABO alleles has led to the need for a comprehensive measure to cover the numerous polymorphisms dispersed in the ABO gene. A few studies have examined the diversity of the O allele compared to A or B subgroup alleles, resulting in antigenic changes. This study investigated the relationship between the serologic and molecular genetic characteristics of the O alleles in the Korean population. Methods: One hundred and five samples from healthy blood group O subjects were selected randomly. The isoagglutinin titer was measured using a tube agglutination and gel microcolumn assay. The ABO alleles were analyzed by sequencing exons 6 and 7 of the ABO gene. When the origin of a heterozygous nucleotide sequence was ambiguous, it was separated into a single allele using mono-allele amplification or cloning. Results: The median IgM isoagglutinin titer was eight. In contrast, the median IgG anti-A and anti-B isoagglutinin titers were 64 and 32, respectively. The IgG isoagglutinin titer showed a significant increase with age (P<0.0001). Six O alleles were observed in 105 blood group O populations by sequencing. The O01 and O02 alleles were common (0.57, 0.36). Three rare O alleles (O04, O05, and O06) and one novel non-deletional O allele were found. Conclusion: The distribution of isoagglutinin titers of blood group O and the genetic frequency of O alleles in this study would form the basis of the development and interpretation of ABO genotyping and serologic workup in the Korean population. (Korean J Blood Transfus 2019;30:124-137)