Brief Communication2022-01-01 Transfusion Medicine
Yousun Chung 
, M.D., Dae-Hyun Ko , M.D., Ph.D., Jihyang Lim , M.D., Ph.D., Kyeong-Hee Kim , M.D., Ph.D., and Hyungsuk Kim , M.D.
Abstract : The number of ABO-incompatible solid organ transplantations (ABOi SOTs) has markedly increased worldwide since the early 2000s. We investigated the choice of ABO group for blood component transfusion in ABOi SOT. We conducted a survey by e-mailing a questionnaire to blood bank specialists at 77 major hospitals in Korea, among whom 34 responded to the survey. In major ABOi SOT, for red blood cells (RBCs), the recipient’s type (70.6%) was the most common choice, followed by group O (29.4%); for platelets, group AB (50.0%) was the most common choice, followed by the donor type (38.2%); for plasma, group AB (55.9%) was the most common choice, followed by the donor type (32.4%). In bidirectional ABOi SOT, for RBCs, the recipient’s type (55.9%) was the most common choice, followed by group O (44.1%); for platelets and plasma, group AB was the most common choice (94.1% and 97.1%, respectively). The policies for transfusion in ABOi SOT were diverse. We suggest a guideline on the choice of ABO group for transfusion in ABOi SOT to secure patient health and enable an efficient use of blood components.
Review Article2022-09-01 Clinical Chemistry
Brian A. Rappold , B.S.
Abstract : Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is increasingly utilized in clinical laboratories because it has advantages in terms of specificity and sensitivity over other analytical technologies. These advantages come with additional responsibilities and challenges given that many assays and platforms are not provided to laboratories as a single kit or device. The skills, staff, and assays used in LC-MS/MS are internally developed by the laboratory, with relatively few exceptions. Hence, a laboratory that deploys LC-MS/MS assays must be conscientious of the practices and procedures adopted to overcome the challenges associated with the technology. This review discusses the post-development landscape of LC-MS/MS assays, including validation, quality assurance, operations, and troubleshooting. The content knowledge of LC-MS/MS users is quite broad and deep and spans multiple scientific fields, including biology, clinical chemistry, chromatography, engineering, and MS. However, there are no formal academic programs or specific literature to train laboratory staff on the fundamentals of LC-MS/MS beyond the reports on method development. Therefore, depending on their experience level, some readers may be familiar with aspects of the laboratory practices described herein, while others may be not. This review endeavors to assemble aspects of LC-MS/MS operations in the clinical laboratory to provide a framework for the thoughtful development and execution of LC-MS/MS applications.
Original Article2021-05-01 Clinical Microbiology
Young Ah Kim , M.D., Hyunsoo Kim , M.D., Young Hee Seo , B.D., Go Eun Park , B.D., Hyukmin Lee , M.D., and Kyungwon Lee , M.D.
Abstract : Background: One health is a flexible concept with many facets, including the environment, community, and the nosocomial super-bacteria resistance network. We investigated the molecular prevalence of extended-spectrum-β-lactamase-producing Escherichia coli (ESBL-EC) in workers, livestock, and the farm environment in Korea. Methods: ESBL-EC isolates were obtained from samples from 19 swine farms, 35 retail stores, seven slaughterhouses, and 45 related workers throughout Korea from August 2017 to July 2018, using ChromID ESBL (BioMérieux, Marcy l’Etoile, France) agar and enrichment broth. The presence of ESBL and mobilized colistin resistance (mcr) genes and antimicrobial resistance were determined. Clonality was evaluated with pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Results: In total, 232 ESBL-EC isolates were obtained from 1,614 non-duplicated samples (14.4% positive rate). The ESBL-EC isolates showed regional and source-related differences. blaCTX-M-55 (N=100), blaCTX-M-14 (N=65), blaCTX-M-15 (N=33), and blaCTX-M-65 (N=23) were common ESBL types. The ESBL-EC isolates showed high resistance rates for various antimicrobial classes; however, all isolates were susceptible to carbapenem. One swine-originating colistin-resistant isolate did not carry any known mcr gene. PFGE was successful for 197 of the 232 isolates, and most PFGE types were heterogeneous, except for some dominant PFGE types (O, R, T, U, and V). MLST of 88 isolates was performed for representative PFGE types; however, no dominant sequence type was observed. Conclusions: The proportion of ESBL-EC in swine industry-related samples was significant, and the isolates harbored common clinical ESBL gene types. These molecular epidemiologic data could provide important evidence for antimicrobial-resistance control through a one health approach.
Brief Communication2021-09-01 Diagnostic Hematology
Ari Ahn , M.D., Chan-Jeoung Park , M.D., Ph.D., Min-sun Kim , M.D., Young-Uk Cho , M.D., Ph.D., Seongsoo Jang , M.D., Ph.D., Mi Hyun Bae , M.D., Ph.D., Jung-Hee Lee , M.D., Ph.D., Je-Hwan Lee , M.D., Ph.D., Kyung-Nam Koh , M.D., Ph.D., and Ho Joon Im , M.D., Ph.D.
Abstract : Myeloid-derived suppressor cells (MDSCs) represent phenotypically heterogeneous populations that suppress tumor-specific T-cell responses. MDSCs are produced from myeloid precursors in emergent states and are increased in several hematologic malignancies. We evaluated the differences in the levels and prognostic significance of MDSCs according to the clinical status of chronic myeloid leukemia (CML). The percentages and numbers of granulocytic (g)MDSCs and monocytic (m)MDSCs in peripheral blood (PB) and bone marrow (BM) aspirates were determined by five-color flow cytometry (HLA-DR/CD11b/CD15/CD33/CD14). The median BM-gMDSC% and PB-gMDSC% of the CML group were lower than those of the complete hematologic response (CHR) and control groups (P
Brief Communication2021-05-01 Clinical Chemistry
Sung Hoon Kim , M.D., Eun Song Song , M.D., Somy Yoon , Ph.D., Gwang Hyeon Eom , Ph.D., Gaeun Kang , M.D., and Young Kuk Cho , M.D.
Abstract : Diagnosis of Kawasaki disease (KD) is occasionally delayed because it is solely based on clinical symptoms. Previous studies have attempted to identify diagnostic biomarkers for KD. Recently, patients with KD were reported to have elevated serum ferritin levels. We investigated the usefulness of the serum ferritin level as a diagnostic biomarker for distinguishing KD from other acute febrile illnesses. Blood samples were obtained from pediatric patients with KD (N=77) and those with other acute febrile illnesses (N=32) between December 2007 and June 2011 for measuring various laboratory parameters, including serum ferritin levels. In patients with KD, laboratory tests were performed at diagnosis and repeated at 2, 14, and 56 days after intravenous immunoglobulin treatment. At the time of diagnosis, serum ferritin levels in patients with KD (188.8 μg/L) were significantly higher than those in patients with other acute febrile illnesses (106.8 μg/L, P=0.003). The serum ferritin cut-off value of 120.8 μg/L effectively distinguished patients with KD from those with other acute febrile illnesses, with a sensitivity and specificity of 74.5% and 83.3%, respectively. Serum ferritin may be a useful biomarker to distinguish KD from other acute febrile illnesses.
Original Article2022-11-01 Transfusion and Cell Therapy
Seung Kwon Koh , B.S., Jeehun Park , Ph.D., Seong-Eun Kim , B.S., Yuree Lim , M.S., Minh-Trang Thi Phan , Ph.D., Jinho Kim , B.S., Ilwoong Hwang , M.D., Yong-Oon Ahn , Ph.D., Sue Shin , M.D., Junsang Doh , Ph.D., and Duck Cho , M.D.
Abstract : Background: Adoptive cell therapy using umbilical cord blood (UCB)-derived allogeneic natural killer (NK) cells has shown encouraging results. However, because of the insufficient availability of NK cells and limited UCB volume, more effective culture methods are required. NK cell expansion and functionality are largely affected by the culture medium. While human serum is a major affecting component in culture media, the way it regulates NK cell functionality remains elusive. We elucidated the effects of different culture media and human serum supplementation on UCB NK cell expansion and functionality. Methods: UCB NK cells were cultured under stimulation with K562-OX40L-mbIL-18/21 feeder cells and IL-2 and IL-15 in serum-containing and serum-free culture media. The effects of the culture media and human serum supplementation on NK cell expansion and cytotoxicity were evaluated by analyzing the expansion rate, activating and inhibitory receptor levels, and the cytotoxicity of the UCB NK cells. Results: The optimal medium for NK cell expansion was Dulbecco’s modified Eagle’s medium/Ham’s F12 with supplements and that for cytotoxicity was AIM V supplemented with Immune Cell Serum Replacement. Shifting media is an advantageous strategy for obtaining several highly functional UCB NK cells. Live cell imaging and killing time measurement revealed that human serum enhanced NK cell proliferation but delayed target recognition, resulting in reduced cytotoxicity. Conclusions: Culture medium supplementation with human serum strongly affects UCB NK cell expansion and functionality. Thus, culture media should be carefully selected to ensure both NK cell quantity and quality for adoptive cell therapy.
Original Article2021-05-01 Clinical Microbiology
Xiang Sun , M.S., Bo Zhang , M.S., Guangjian Xu , M.S., Junwen Chen , M.S., Yongpeng Shang , Ph.D., Zhiwei Lin , Ph.D., Zhijian Yu , M.D., Jinxin Zheng , M.D., and Bing Bai , M.D.
Abstract : Background: Tigecycline, eravacycline, and omadacycline are recently developed tetracyclines. Susceptibility of microbes to these tetracyclines and their molecular mechanisms have not been well elucidated. We investigated the susceptibility of Moraxella catarrhalis to tigecycline, eravacycline, and omadacycline and its resistance mechanisms against these tetracyclines. Methods: A total of 207 non-duplicate M. catarrhalis isolates were collected from different inpatients. The minimum inhibitory concentrations (MICs) of the tetracyclines were determined by broth microdilution. Tigecycline-, eravacycline-, or omadacycline-resistant isolates were induced under in vitro pressure. The tet genes and mutations in the 16S rRNA was detected by PCR and sequencing. Results: Eravacycline had a lower MIC50 (0.06 mg/L) than tigecycline (0.125 mg/L) or omadacycline (0.125 mg/L) against M. catarrhalis isolates. We found that 136 isolates (65.7%) had the tetB gene, and 15 (7.2%) isolates were positive for tetL; however, their presence was not correlated with high tigecycline, eravacycline, or omadacycline (≥1 mg/L) MICs. Compared with the initial MIC after 160 days of induction, the MICs of tigecycline or eravacycline against three M. catarrhalis isolates increased ≥eight-fold, while those of omadacycline against two M. catarrhalis isolates increased 64-fold. Mutations in the 16S rRNA genes (C1036T and/or G460A) were observed in omadacycline-induced resistant isolates, and increased RR (the genes encoding 16SrRNA (four copies, RR1-RR4) copy number of 16S rRNA genes with mutations was associated with increased resistance to omadacycline. Conclusions: Tigecycline, eravacycline, and omadacycline exhibited robust antimicrobial effects against M. catarrhalis. Mutations in the 16S rRNA genes contributed to omadacycline resistance in M. catarrhalis.
Review Article2022-05-01 Diagnostic Genetics
Namhee Kim , M.D., Sun-Young Kong , M.D., Ph.D., Jongha Yoo , M.D., Ph.D., Do-Hoon Kim , M.D., Ph.D., Soo Hyun Seo , M.D., and Jieun Kim , M.D., Ph.D.
Abstract : Genetic testing has become increasingly integrated into all areas of healthcare, and complex genetic testing usage continues to grow; thus, the demand for genetic counseling (GC) is likely to increase. However, it is unclear whether the current clinical GC capacity is sufficient for meeting the existing demand. This review describes the current issues, challenges, and future perspectives of GC in Korea based on a professional survey conducted among laboratory physicians. In view of the growing GC demand in the clinical setting, participants expressed a concern about the lack of support from the national healthcare insurance policy and legal requirements, such as certification, for GC practice. The implementation of genetic testing in the overall healthcare system in Korea is in an early phase. Proper implementation can be achieved through education and training of specialists, collaboration among healthcare personnel, proper regulatory oversight, genomic policies, and public awareness. Understanding the current GC capacity, issues, and challenges is a prerequisite for effective strategic planning by healthcare systems considering the expected growth in the demand for clinical genetic services over the next few decades.
Original Article2022-03-01 Diagnostic Immunology
Mina Hur , M.D., Ph.D., Mikyoung Park , M.D., Ph.D., Hee-Won Moon , M.D., Ph.D., Won Hyeok Choe , M.D., Ph.D., and Chae Hoon Lee , M.D., Ph.D.
Abstract : Background: Non-invasive clinical algorithms for the detection of liver fibrosis (LF) can reduce the need for liver biopsy (LB). We explored the implementation of two serum biomarkers, enhanced liver fibrosis (ELF) and Mac-2 binding protein glycosylation isomer (M2BPGi), in clinical algorithms for LF in chronic hepatitis B (CHB) patients. Methods: Two clinical algorithms were applied to 152 CHB patients: (1) transient elastography (TE) followed by biomarkers (TE/ELF and TE/M2GPGi); (2) biomarker test followed by TE (ELF/TE and M2BPGi/TE). Using the cut-off value or index for the detection of advanced LF (TE≥F3; 9.8 in ELF and 3.0 in M2BPGi), LB was expected to be performed in cases with discordant TE and biomarker results. Results: In both algorithms, the expected number of LBs was lower when using M2BPGi than when using ELF (TE/ELF or ELF/TE, 13.2% [N=20]; TE/M2BPGi or M2BPGi/TE, 9.9% [N=15]), although there was no statistical difference (P=0.398). In the TE low-risk group (TE≤F2), the discordance rate was significantly lower in the TE/M2BPGi approach than in the TE/ELF approach (1.5% [2/136] vs. 11.0% [15/136], P=0.002). In the biomarker low-risk group, there was no significant difference between the ELF/TE and M2BPGi/TE approaches (3.9% [5/126] vs. 8.8% [13/147], P=0.118). Conclusions: Both ELF and M2BPGi can be implemented in non-invasive clinical algorithms for assessing LF in CHB patients. Given the lowest possibility of losing advanced LF cases in the low-risk group when using the TE/M2BPGi approach, this combination seems useful in clinical practice.
Original Article2021-05-01 Diagnostic Immunology
Se Young Jang , M.D., Won Young Tak , M.D., Soo Young Park , M.D., Young-Oh Kweon , M.D., Yu Rim Lee , M.D., Gyeonghwa Kim , Ph.D., Keun Hur , Ph.D., Man-Hoon Han , M.D., and Won Kee Lee , Ph.D.
Abstract : Background: Mac-2 binding protein glycosylation isomer (M2BPGi) has been established as a non-invasive biomarker for liver fibrosis. We evaluated the diagnostic efficacy of M2BPGi compared with those of other liver fibrosis markers in liver fibrosis in non-alcoholic fatty liver disease (NAFLD). Methods: We analyzed serum M2BPGi levels in 113 NAFLD patients. A pathologist graded liver fibrosis histopathologically. The diagnostic efficacies of serum M2BPGi and other liver fibrosis markers (aspartate aminotransferase to platelet ratio index, fibrosis index based on four factors, and NAFLD fibrosis score [NFS]) were evaluated using correlation, area under the ROC curve (AUC), logistic regression, and C-statistics. Results: Serum M2BPGi level and other liver fibrosis markers showed a moderate correlation with fibrosis grade. The AUC values of M2BPGi were 0.761, 0.819, 0.866, and 0.900 for diagnosing fibrosis (F)>0, F>1, F>2, and F>3, respectively. Logistic regression analysis showed M2BPGi as the only independent factor associated with F>2 and F>3. Although C-statistics showed that NFS was the best diagnostic factor for F>2 and F>3, M2BPGi with NFS had an increased C-statistics value, indicating that it is a better diagnostic model. Conclusions: The serum M2BPGi level increased with liver fibrosis severity and could be a good biomarker for diagnosing advanced fibrosis and cirrhosis in NAFLD patients. A well-controlled, prospective study with a larger sample size is needed to validate the diagnostic power of M2BPGi and other fibrosis markers in NAFLD.
Full Text
PDF
Pubmed
PMC
