1.Correlation Between C3d Assay and Single Antigen Bead Assay for Detection of Human Leukocyte Antigen Class II Antibodies
Hyein KANG ; Do-Hoon KIM ; Jung Sook HA ; Namhee RYOO ; Dong-Seok JEON ; Wonmok LEE
Laboratory Medicine Online 2020;10(4):295-300
Background:
Detection of anti-human leukocyte antigen (HLA) antibodies is important during the selection of an appropriate donor prior to organ transplantation and also for monitoring the patients after transplantation. In this study, we compared antibodies detected via C3d assays, which monitors C3d complement-binding activities of HLA antibodies with those detected via single antigen bead (SAB) assays.
Methods:
A total of 66 serum samples were tested in parallel by SAB assays (Immucor Transplant Diagnostics, USA) and C3d assays (Immucor) for the detection of HLA class II antibodies. The relationship between these two methods was analyzed based on the types, numbers, median fluorescent intensity (MFI) values, and positivity of the antibodies using MATCH IT! Antibody (Immucor) program.
Results:
The number of antibodies obtained based on SAB and C3d assays was the highest with 24 samples (36.4%) in the 11–20 range and 23 (34.8%) in the 2–5 range detected via each assay. Among the SAB-positive antibodies, only 28 (6.4%) of the 440 antibodies with MFI ≤3,000 were C3d-positive, and 341 (61.3%) of the 556 antibodies with MFI ≥3,001 were C3d-positive. Whereas, among the 442 C3d-positive antibodies, SAB assays were positive except for 32 (7.2%) and 41 (9.3%) antibodies in the sections of MFI ≤500 and 1,001 ≤MFI ≤10,000, respectively. C3d-positive samples had higher maximum MFI values based on SAB assays, compared with C3d-negative samples.
Conclusions
MFI values of HLA class II antibodies detected through SAB assays in C3d-positive samples were higher than those in C3d-negative samples.
2.Correlation Between C3d Assay and Single Antigen Bead Assay for Detection of Human Leukocyte Antigen Class II Antibodies
Hyein KANG ; Do-Hoon KIM ; Jung Sook HA ; Namhee RYOO ; Dong-Seok JEON ; Wonmok LEE
Laboratory Medicine Online 2020;10(4):295-300
Background:
Detection of anti-human leukocyte antigen (HLA) antibodies is important during the selection of an appropriate donor prior to organ transplantation and also for monitoring the patients after transplantation. In this study, we compared antibodies detected via C3d assays, which monitors C3d complement-binding activities of HLA antibodies with those detected via single antigen bead (SAB) assays.
Methods:
A total of 66 serum samples were tested in parallel by SAB assays (Immucor Transplant Diagnostics, USA) and C3d assays (Immucor) for the detection of HLA class II antibodies. The relationship between these two methods was analyzed based on the types, numbers, median fluorescent intensity (MFI) values, and positivity of the antibodies using MATCH IT! Antibody (Immucor) program.
Results:
The number of antibodies obtained based on SAB and C3d assays was the highest with 24 samples (36.4%) in the 11–20 range and 23 (34.8%) in the 2–5 range detected via each assay. Among the SAB-positive antibodies, only 28 (6.4%) of the 440 antibodies with MFI ≤3,000 were C3d-positive, and 341 (61.3%) of the 556 antibodies with MFI ≥3,001 were C3d-positive. Whereas, among the 442 C3d-positive antibodies, SAB assays were positive except for 32 (7.2%) and 41 (9.3%) antibodies in the sections of MFI ≤500 and 1,001 ≤MFI ≤10,000, respectively. C3d-positive samples had higher maximum MFI values based on SAB assays, compared with C3d-negative samples.
Conclusions
MFI values of HLA class II antibodies detected through SAB assays in C3d-positive samples were higher than those in C3d-negative samples.
3.Two Cases of Successful Plasma Exchange with Unfractionated Heparin Anticoagulation in Patients Exhibiting Anaphylaxis to Acid-citrate-dextrose Formula A
Hyein KANG ; Do-Hoon KIM ; Dong-Seok JEON ; Wonmok LEE ; Namhee RYOO ; Jungsook HA
Korean Journal of Blood Transfusion 2020;31(1):55-60
Plasma exchange performed with the aid of acid-citrate-dextrose formula A (ACD-A) is generally regarded as safe. However, unfractionated heparin (UFH) can serve as an anticoagulant for patients experiencing serious side effects such as anaphylaxis. No guidelines have currently been defined for the stand-alone UFH dosing during plasma exchange. We describe here two patients who developed anaphylaxis to ACD-A during plasma exchange, and we successfully used UFH as a standalone anticoagulant. The first patient was a 55-year-old man who required plasma exchange before ABO-incompatible kidney transplantation. During plasma exchange, he developed an allergic reaction. Thereafter, UFH was used as a standalone anticoagulant during four sessions of plasma exchange; the UFH (5,000 units) was added to a 500 mL normal saline bag and the UFH:whole blood ratio was maintained at 1:28. The second patient was an 80-year-old woman with steroid pulse-resistant neuromyelitis optica. She developed an allergic reaction during the first session of plasma exchange. The patient subsequently underwent five successful sessions of plasma exchange using UFH as a standalone anticoagulant. These findings may be useful when establishing a protocol for UFH as a standalone anticoagulant during plasma exchange in patients who develop an allergic reaction to citrate.
4.First Case of Cellular Cannibalism in Small-Cell Carcinoma of the Bladder Detected in Peripheral Blood
Hyein KANG ; Do Hoon KIM ; Wonmok LEE ; Jungsook HA ; Namhee RYOO ; Dong Seok JEON ; Hye Ra JUNG
Annals of Laboratory Medicine 2019;39(4):400-402
No abstract available.
Cannibalism
;
Urinary Bladder
5.Improvement in External Quality Assessment Results for Qualitative Fecal Immunochemical Tests in Korea After Feedback to Manufacturers
Wonmok LEE ; Namhee RYOO ; Hun Seok SUH ; Chang Ho JEON ; ;
Annals of Laboratory Medicine 2019;39(6):584-586
No abstract available.
Korea
6.BRCA1/2 mutations, including large genomic rearrangements, among unselected ovarian cancer patients in Korea.
Do Hoon KIM ; Chi Heum CHO ; Sun Young KWON ; Nam Hee RYOO ; Dong Seok JEON ; Wonmok LEE ; Jung Sook HA
Journal of Gynecologic Oncology 2018;29(6):e90-
OBJECTIVE: We performed small-scale mutation and large genomic rearrangement (LGR) analysis of BRCA1/2 in ovarian cancer patients to determine the prevalence and the characteristics of the mutations. METHODS: All ovarian cancer patients who visited a single institution between September 2015 and April 2017 were included. Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA), and long-range polymerase chain reaction (PCR) were performed to comprehensively study BRCA1/2. The genetic risk models BRCAPRO, Myriad, and BOADICEA were used to evaluate the mutation analysis. RESULTS: In total, 131 patients were enrolled. Of the 131 patients, Sanger sequencing identified 16 different BRCA1/2 small-scale mutations in 20 patients (15.3%). Two novel nonsense mutations were detected in 2 patients with a serous borderline tumor and a large-cell neuroendocrine carcinoma. MLPA analysis of BRCA1/2 in Sanger-negative patients revealed 2 LGRs. The LGRs accounted for 14.3% of all identified BRCA1 mutations, and the prevalence of LGRs identified in this study was 1.8% in 111 Sanger-negative patients. The genetic risk models showed statistically significant differences between mutation carriers and non-carriers. The 2 patients with LGRs had at least one blood relative with breast or ovarian cancer. CONCLUSION: Twenty-two (16.8%) of the unselected ovarian cancer patients had BRCA1/2 mutations that were detected through comprehensive BRCA1/2 genetic testing. Ovarian cancer patients with Sanger-negative results should be considered for LGR detection if they have one blood relative with breast or ovarian cancer. The detection of more BRCA1/2 mutations in patients is important for efforts to provide targeted therapy to ovarian cancer patients.
Breast
;
Carcinoma, Neuroendocrine
;
Codon, Nonsense
;
Female
;
Genetic Testing
;
Humans
;
Korea*
;
Multiplex Polymerase Chain Reaction
;
Ovarian Neoplasms*
;
Ovary
;
Polymerase Chain Reaction
;
Prevalence
7.Abnormal Urinalysis Results Caused by Interfering Substances.
Wonmok LEE ; Yukyung KIM ; Soonhee CHANG ; A Jin LEE ; Chang Ho JEON
Journal of Laboratory Medicine and Quality Assurance 2017;39(2):76-82
BACKGROUND: To understand causes of abnormal reaction for the urinalysis, we analyze the interfering substances of clinical urine samples. We focused the effect of urinary vitamin C and fluorescein sodium to the urine chemistry especially glucose, hemoglobin, and leukocyte esterase. METHODS: Incidence of urinary vitamin C was determined for patients and people underwent a medical check–up. We decided dipstick results of glucose, hemoglobin, and leukocyte esterase as false negative based on urine sediment and serum glucose results. Dipstick urinalysis was tested by URiSCAN Pro III with URiSCAN 11 strip (YD Diagnostics, Korea). Urine sediments tests were performed by manual microscopic analysis or Sysmex UF–1000i (Sysmex Co., Japan). RESULTS: The incidence of vitamin C was 20.4% for all subjects. The positive rate of the medical check-up group (34.6%) was higher than others. When vitamin C was detected in clinical urine samples, 42.3%, 10.6%, and 8.2% were defined as false negative for glucose, hemoglobin, and leukocyte esterase dipstick tests, respectively. Fluorescein sodium also interfered on the results of hemoglobin and leukocyte esterase of the dipstick reagents. CONCLUSIONS: Vitamin C was frequently found in the clinical urine samples, and its incidence was higher in the people who underwent medical check-up. The urinary vitamin C and fluorescein sodium can cause interferences in urine dipstick results. Thus, it is expected that present study will give useful information to predict false negative rates of urine dipstick tests by vitamin C and fluorescein sodium.
Ascorbic Acid
;
Blood Glucose
;
Chemistry
;
Fluorescein
;
Glucose
;
Humans
;
Incidence
;
Indicators and Reagents
;
Leukocytes
;
Urinalysis*
8.Comparison and Evaluation of Diagnostic Assays for Clostridium difficile Infection.
Kyoung Bo KIM ; Do Hoon KIM ; Wonmok LEE ; Jung Sook HA ; Nam Hee RYOO ; Dong Seok JEON ; Jae Ryong KIM
Laboratory Medicine Online 2017;7(2):73-78
BACKGROUND: Clostridium difficile is a leading causative microorganism of pseudomembranous colitis (PMC) and antibiotic-associated diarrhea. In patients who have a history of antibiotic use and diarrhea, the presence of the C. difficile toxin should be confirmed to diagnose C. difficile infection (CDI). In this study, the results of three assays for CDI, which were performed on 1,363 clinical stool samples at a tertiary hospital, were analyzed to evaluate the performance and usefulness of these assays for diagnosis of CDI. METHODS: The results of the VIDAS C. difficile Toxin A&B Immunoassay (bioMérieux SA, France), Xpert C. difficile Real-Time PCR Assay (Cepheid, USA), and ChromID C. difficile Agar (bioMérieux SA, France) culture were analyzed retrospectively. Cases were defined as CDI according to the positive Xpert assay or the positive VIDAS assay and/or culture in the presence of PMC findings after radiological imaging or endoscopic procedures. RESULTS: A total of 1,027 samples (75.8%) tested negative in all three assays, 101 samples (7.4%) tested positive in all three assays, and overall agreement among them was 82.7%. In this study, 291 cases (21.3%) were diagnosed as CDI. Sensitivity and specificity of the VIDAS assay were 38.8% and 99.3%, and those of ChromID culture were 71.5% and 96.5%, respectively. The Xpert assay showed good sensitivity (98.6%, 287/291), whereas the VIDAS assay and ChromID culture showed low sensitivities. CONCLUSIONS: These results suggest that rapid molecular diagnostic assays, such as the Xpert assay, are promising candidates for an initial diagnostic test for CDI.
Agar
;
Clostridium difficile*
;
Clostridium*
;
Diagnosis
;
Diagnostic Tests, Routine
;
Diarrhea
;
Enterocolitis, Pseudomembranous
;
Humans
;
Immunoassay
;
Molecular Diagnostic Techniques
;
Pathology, Molecular
;
Real-Time Polymerase Chain Reaction
;
Retrospective Studies
;
Sensitivity and Specificity
;
Tertiary Care Centers
9.Evaluation of VITEK Mass Spectrometry (MS), a Matrix-Assisted Laser Desorption Ionization Time-of-Flight MS System for Identification of Anaerobic Bacteria.
Wonmok LEE ; Myungsook KIM ; Dongeun YONG ; Seok Hoon JEONG ; Kyungwon LEE ; Yunsop CHONG
Annals of Laboratory Medicine 2015;35(1):69-75
BACKGROUND: By conventional methods, the identification of anaerobic bacteria is more time consuming and requires more expertise than the identification of aerobic bacteria. Although the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) systems are relatively less studied, they have been reported to be a promising method for the identification of anaerobes. We evaluated the performance of the VITEK MS in vitro diagnostic (IVD; 1.1 database; bioMerieux, France) in the identification of anaerobes. METHODS: We used 274 anaerobic bacteria isolated from various clinical specimens. The results for the identification of the bacteria by VITEK MS were compared to those obtained by phenotypic methods and 16S rRNA gene sequencing. RESULTS: Among the 249 isolates included in the IVD database, the VITEK MS correctly identified 209 (83.9%) isolates to the species level and an additional 18 (7.2%) at the genus level. In particular, the VITEK MS correctly identified clinically relevant and frequently isolated anaerobic bacteria to the species level. The remaining 22 isolates (8.8%) were either not identified or misidentified. The VITEK MS could not identify the 25 isolates absent from the IVD database to the species level. CONCLUSIONS: The VITEK MS showed reliable identifications for clinically relevant anaerobic bacteria.
Bacteria, Anaerobic/*genetics/isolation & purification
;
Bacterial Typing Techniques/*instrumentation/*methods
;
Body Fluids/microbiology
;
Databases, Genetic
;
Humans
;
RNA, Ribosomal, 16S/*analysis/metabolism
;
Sequence Analysis, DNA
;
*Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
10.Acute Cellulitis Caused by Neisseria skkuensis.
Sung Gyun PARK ; Kyoung Bo KIM ; Wonmok LEE ; Jung Sook HA ; Namhee RYOO ; Dong Seok JEON ; Jae Ryong KIM ; Hyun Ah KIM ; Seong Yeol RYU
Annals of Clinical Microbiology 2015;18(1):33-36
A 73-year-old man visited our hospital because of pain with swelling and redness on the right foot dorsum. He was diagnosed with liver cirrhosis and nodular hepatic cellular carcinoma. Lower extremity CT scan and MRI showed abscess formation in the right foot dorsum. Gram-negative cocci were recovered from the culture of drained pus at the site and identified as Neisseria skkuensis by 16S rRNA gene sequencing. Here, we report the first case of cellulitis due to N. skkuensis and provide a literature review.
Abscess
;
Aged
;
Cellulitis*
;
Foot
;
Genes, rRNA
;
Humans
;
Liver Cirrhosis
;
Lower Extremity
;
Magnetic Resonance Imaging
;
Neisseria*
;
RNA, Ribosomal, 16S
;
Sequence Analysis
;
Suppuration
;
Tomography, X-Ray Computed

Result Analysis
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