1.Emergence of Monosomy 7 in Philadelphia-Negative Cells during MDS Development and not CML Diagnosis Proved by Serial Droplet Digital PCR
Sholhui PARK ; Yeung Chul MUN ; Chu-Myong SEONG ; Jungwon HUH
Laboratory Medicine Online 2020;10(4):321-325
Emergence of new clonal chromosomal abnormality (CCA) has been reported in Philadelphia-negative cells in patients with chronic myeloid leukemia (CML) undergoing the tyrosine kinase inhibitor (TKI) treatment. However, the time of emergence and clinical significance of CCA remains to be elucidated. In this study, we report a CML patient undergoing TKI treatment who developed myelodysplastic syndrome (MDS) after 206 months since the diagnosis of CML. Results of droplet digital PCR performed with serial bone marrow samples revealed that monosomy 7 in Philadelphia-negative cells appeared at the time of MDS development that did not exist initially at the time of CML diagnosis.
2.Emergence of Monosomy 7 in Philadelphia-Negative Cells during MDS Development and not CML Diagnosis Proved by Serial Droplet Digital PCR
Sholhui PARK ; Yeung Chul MUN ; Chu-Myong SEONG ; Jungwon HUH
Laboratory Medicine Online 2020;10(4):321-325
Emergence of new clonal chromosomal abnormality (CCA) has been reported in Philadelphia-negative cells in patients with chronic myeloid leukemia (CML) undergoing the tyrosine kinase inhibitor (TKI) treatment. However, the time of emergence and clinical significance of CCA remains to be elucidated. In this study, we report a CML patient undergoing TKI treatment who developed myelodysplastic syndrome (MDS) after 206 months since the diagnosis of CML. Results of droplet digital PCR performed with serial bone marrow samples revealed that monosomy 7 in Philadelphia-negative cells appeared at the time of MDS development that did not exist initially at the time of CML diagnosis.
3.Application of Six Sigma Metrics to Improve Quality Control for Point-of-care Glucose Testing
Sholhui PARK ; Wookeun LEE ; Tae-Dong JEONG ; Hae-Sun CHUNG ; Ki-Sook HONG
The Ewha Medical Journal 2020;43(3):43-48
Objectives:
Six sigma is a quality management system for the assessment of precisionand accuracy. We aim to apply the six sigma rule to quality control (QC) of point-of-care(POC) glucose meters in a tertiary hospital.
Methods:
Thirty POC glucose meters installed at Ewha Womans University MokdongHospital were monitored between January 2013 and March 2014. The QC data fromthe POC glucose meters at low and high levels were collected. The monthly mean, standarddeviation, bias, coefficient of variation, and mean sigma metrics were calculated.The correlation between accuracy and precision was assessed based on the percentagebias and coefficient of variation. Comprehensive instructions on the QC and maintenanceof the devices were provided in the departments with poor sigma scores. Afollow-up assessment was performed after the intervention.
Results:
The mean sigma values for the low and high controls were 3.29 and 3.71, respectively.At the low and high controls, 36.6% and 10% of the glucose meters showeda sigma value <3. The causes of low sigma values included the use of expired controlmaterials, prolonged air exposure of the sample strip, lack of user training, and errors indevice maintenance. On follow-up monitoring for 3 months following QC intervention,23.3% (low control) and 6.6% (high control) of the glucose meters scored a sigma value<3, indicating improved QC.
Conclusion
Sigma metrics-based QC can successfully improve accuracy and precisionof POC glucose meters in an objective and quantitative manner and can be usedfor follow up after QC intervention.
4.Performance of Xpert Carba-R Assay for Identification of Carbapenemase Gene in the Clinical Microbiology Laboratory
Hae-Sun CHUNG ; Naery YANG ; Yihyeon KIM ; Miae LEE ; Sholhui PARK
The Ewha Medical Journal 2020;43(3):39-42
Objectives:
The Xpert Carba-R Assay is a diagnostic test designed for the rapid detectionand differentiation of the blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP-1 genes. We verifiedthe performance of Xpert Carba-R Assay for identification of carbapenemase genein the clinical microbiology laboratory.
Methods:
The analytical limit of detection was determined with two suspensions ofcarbapenemase-producing Enterobacteriaceae (CPE) isolates (KPC and NDM). A totalof 52 specimens were evaluated: 21 bacterial isolates from clinical specimens, 21 rectalswabs, and 10 contrived stool specimens.
Results:
In bacterial isolates, concordant results between the Xpert Carba-R Assayand PCR were found in 20 of 21; 8 KPC, 8 NDM, 1 IMP, and 2 multiple carbapenamasegenes (KPC/NDM, NDM/OXA) were detected both by Xpert Carba-R Assay and PCR.In one GES-positive isolate, Xpert Carba-R Assay showed a negative result as expected.One VIM-positive isolate tested negative by Xpert Carba-R Assay. Complete concordancewas seen in rectal swab specimens: 4 specimens with KPC and 17 specimenswith negative results both by Xpert Carba-R Assay and surveillance culture. Among the10 contrived stool specimens, Xpert Carba-R Assay detected carbapenemase genes in9 specimens as expected according to the CPE strains spiked into the contrived stool; 2KPC, 4 NDM, 1 IMP, and 2 multiple carabapenamase genes (NDM/KPC, NDM/OXA).One VIM-positive specimen tested negative by Xpert Carba-R Assay.
Conclusion
In conclusion, the Xpert Carba-R Assay can be used to identify carbapenemasegene in bacterial isolates cultured from clinical specimens and detect CPE carrierusing rectal swab in clinical laboratories.
5.Estimated Glomerular Filtration Rates Show Minor but Significant Differences Between the Single and Subgroup Creatinine-Based Chronic Kidney Disease Epidemiology Collaboration Equations
Annals of Laboratory Medicine 2019;39(2):205-208
The creatinine-based Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation can be calculated according to race, sex, and creatinine concentration (subgroup equation) or in the form expressed by one equation (single equation). Minor differences in the constants used in the CKD-EPI equations (subgroup vs single equations) could result in a significant difference in the estimated glomerular filtration rate (eGFR). We evaluated the impact of this difference in 79,709 Korean patients. The eGFR was calculated as an integer using the single and subgroup CKD-EPI equations. The differences in eGFR and GFR categories between the equations were analyzed. eGFR was higher in the subgroup equation than the single equation by 1 mL/min/1.73 m² for 12,476 (27.4%) Korean females. The GFR category based on the subgroup equation was reclassified using the single equation for 352 (0.77%) females. Based on the results, the constant of the single equation was optimized. There was no difference in eGFR values between equations using a multiplier of 1.0213 instead of 1.018 for the “white or other” females constant in the single CKD-EPI equation. Clinicians should carefully apply the CKD-EPI equation because eGFR values may differ by 1 mL/min/1.73 m² depending on the manner of calculation. To minimize these differences, the constants of the single equation should be revised.
Continental Population Groups
;
Cooperative Behavior
;
Creatinine
;
Epidemiology
;
Female
;
Glomerular Filtration Rate
;
Humans
;
Renal Insufficiency, Chronic
6.A Clue to Discovering Unstable Hemoglobin Variants via Abnormal WBC Differential Scattergrams Using the Sysmex Automated Hematology Analyzer
Sholhui PARK ; Tae Dong JEONG ; Ki Sook HONG ; Jungwon HUH
Laboratory Medicine Online 2019;9(2):84-87
Incidentally, hemoglobin (Hb) variants can be detected using HbA1c tests in clinical laboratories. We found 38 patients with Hb variants after reviewing a total of 29,398 HbA1c test results from January 2017 to December 2017. While reviewing the complete blood count results of the patients (N=36) using the Sysmex XN-9000 analyzer (Sysmex, Japan), 35 patients were flagged as unremarkable with respect to differential white blood cell (WBC) counts. However, 1 patient with a normal WBC count did not obtain a differential WBC count while being flagged for an abnormal WBC scattergram in the white blood cell differential (WDF) channel. The WBC histogram showed an abnormally low fluorescent signal in the WDF channel; however, the differential WBC count was normal upon microscopic examination. After testing the patient's buffy coat suspended in normal saline and removing red blood cells (RBCs), the WBC scattergram and differential WBC count returned to normal. This finding suggests that the presence of a patient's RBCs may affect WBC scattergrams and Hb variants may interfere with the fluorescent dye in the differential WBC count. Therefore, when an abnormal WBC scattergram with an abnormally low fluorescent signal is encountered on the Sysmex XN-9000 analyzer, the presence of an Hb variant can be suspected.
Blood Cell Count
;
Erythrocytes
;
Hematology
;
Humans
;
Leukocytes
7.Effects of Pre-analytical Variables on Cell-free DNA Extraction for Liquid Biopsy
Tae Dong JEONG ; Mi Hwa KIM ; Sholhui PARK ; Hae Sun CHUNG ; Jin Wha LEE ; Jung Hyun CHANG ; Jungwon HUH
Laboratory Medicine Online 2019;9(2):45-56
BACKGROUND: Extraction of cell-free DNA (cfDNA) is a key step for determining the quality of cfDNA-related molecular diagnostics. We evaluated the effect of sample containers and sample storage conditions on cfDNA extraction. METHODS: The cfDNA extraction using the MagMAX Cell-Free DNA Isolation Kit from five healthy controls and five lung cancer patients was evaluated according to the type of sample container and storage conditions: K2-EDTA container, <1, 6, 24, and 48 hr storage at 4℃ after immediate plasma separation; and Cell-Free DNA BCT container, <1, 3, 7, and 14 days stored at room temperature. Mutation analysis of EGFR exons 18–21 was performed. To assess the effect of a delay in centrifugation, EDTA whole blood samples from five healthy individuals were stored at 4℃ for 6, 12, and 24 hr before plasma separation. RESULTS: There was no significant difference in the amount and nucleic acid size of cfDNA in both controls and patients with cancer when EDTA plasma was stored at 4℃ up to 48 hr. The amount and size of cfDNA in the BCT container were not different up to 7 days; however, the 14-day sample showed an increase in cfDNA concentration due to genomic DNA contamination. EGFR mutations were detected on EDTA containers up to 48 hr and with BCT containers up to 14 days. When EDTA whole blood was stored at 4℃ and plasma separation was delayed, the cfDNA concentration increased from 24 hr. CONCLUSIONS: The cfDNA extraction was affected by the sample containers and storage conditions.
Biopsy
;
Centrifugation
;
DNA Contamination
;
DNA
;
Edetic Acid
;
Exons
;
Humans
;
Lung Neoplasms
;
Pathology, Molecular
;
Plasma
8.Analytical Performance of INNOVANCE Free Protein S Antigen on Sysmex CS-5100.
Sholhui PARK ; Sanghee PARK ; Jungsoo LEE ; Jungwon HUH
Laboratory Medicine Online 2019;9(1):1-5
BACKGROUND: Protein S deficiency is a common cause of thrombophilia. Free protein S has been suggested as one of the best screening tests for this deficiency. We evaluated an immunoturbidimetric free protein S reagent, INNOVANCE Free Protein S Antigen (Free PS Ag; Siemens Healthcare Diagnostics, Germany), using a CS-5100 coagulation analyzer (Sysmex, Japan). METHODS: The performance of INNOVANCE Free PS Ag was evaluated according to the CLSI guidelines. Precision, linearity, and verification of reference intervals were examined. The INNOVANCE Free PS Ag was also compared by the STA-Liatest Free Protein S immunoturbidimetric assay (Diagnostica Stago, France). RESULTS: The repeatability and within-laboratory imprecision of INNOVANCE Free PS Ag were 0.8% CV and 2.0% CV at the normal level, and 1.3% CV and 2.3% CV at the abnormally low level, respectively. This assay showed linearity from 4.0% to 151.9% (correlation coefficient r=1, P < 0.0001). Reference intervals for males and females were verified as acceptable. INNOVANCE Free PS Ag was comparable with STA-Liatest Free Protein S with a very high correlation (r=0.935, P < 0.0001). The results for the INNOVANCE antigen were higher. CONCLUSIONS: The INNOVANCE Free PS Ag on a Sysmex CS-5100 coagulation analyzer has excellent analytical performance and is comparable with the STA-Liatest Free Protein S assay.
Delivery of Health Care
;
Female
;
Humans
;
Male
;
Mass Screening
;
Protein S Deficiency
;
Protein S*
;
Thrombophilia
9.Anaplastic Large Cell Lymphoma with Massive Eosinophilia and Complex Karyotype Initially Misdiagnosed as Chronic Eosinophilic Leukemia.
Min Kyung SO ; Sholhui PARK ; Min Sun CHO ; Yeung Chul MUN ; Jungwon HUH
Laboratory Medicine Online 2018;8(2):56-61
We report a patient with massive eosinophilia and a complex karyotype that was initially misdiagnosed as chronic eosinophilic leukemia (CEL), but later diagnosed as anaplastic large cell lymphoma (ALCL) masked by massive eosinophilia. The complex karyotype observed at initial diagnosis remained unchanged later, after the evidence of bone marrow involvement of ALCL was obtained. At diagnosis, genetic aberrations corresponding to metaphase cytogenetics were not identified by interphase fluorescence in situ hybridization, although abnormal results were noted at follow-up. Together, these observations indicate that the complex karyotype at initial work-up has been derived from a low proportion of lymphoma cells with high mitotic ability that were not identified by microscopy, rather than from massive eosinophils. These findings suggest that our patient had ALCL with secondary eosinophilia rather than CEL since initial diagnosis.
Bone Marrow
;
Cytogenetics
;
Diagnosis
;
Eosinophilia*
;
Eosinophils*
;
Fluorescence
;
Follow-Up Studies
;
Humans
;
Hypereosinophilic Syndrome*
;
In Situ Hybridization
;
Interphase
;
Karyotype*
;
Lymphoma
;
Lymphoma, Large-Cell, Anaplastic*
;
Masks
;
Metaphase
;
Microscopy
10.Variable Natural Killer Cell Activity in Hematological Malignancies at Diagnosis.
Sholhui PARK ; Yeung Chul MUN ; Chu Myong SEONG ; Hee Jin HUH ; Jungwon HUH
Laboratory Medicine Online 2018;8(2):41-51
BACKGROUND: Natural killer (NK) cells play a key role in innate immune responses and are an important component of anti-cancer defenses. This study aimed to investigate the clinicopathological characteristics of NK cell activity (NKA) among various hematological malignancies at diagnosis and to evaluate their clinical value as a monitoring marker. METHODS: A total of 111 patients that were newly diagnosed with hematological malignancies were recruited, comprising 18 acute myeloid leukemia (AML), 31 multiple myeloma (MM), and 62 lymphoma. Twenty-three normal control subjects from our health examination center were recruited. NKA was measured using a commercially available enzyme-linked immunosorbent assay kit, which measures interferon-gamma secreted by ex vivo-stimulated NK cells in whole blood. RESULTS: The 111 patients had a median NKA of 202.80 pg/mL (range 40–2,000). NKA was significantly decreased in patients with AML (median 47.05 pg/mL, 40–2,000, P<0.0001), MM (275.00, 40–2,000, P<0.0001), and lymphoma (289.49, 40–2,000, P<0.0001) compared with that in normal controls (1,891, 412–2,000). There was a difference in NKA between AML and lymphoma (P=0.0499). Serial changes in NKA correlated with disease progression. NKA did not correlate with the NK cell count in any group of hematological malignancies. CONCLUSIONS: The measurement of NKA could be useful to evaluate the immunological status in hematological malignancies at diagnosis and during follow-up.
Diagnosis*
;
Disease Progression
;
Enzyme-Linked Immunosorbent Assay
;
Follow-Up Studies
;
Hematologic Neoplasms*
;
Humans
;
Immunity, Innate
;
Interferon-gamma
;
Killer Cells, Natural*
;
Leukemia, Myeloid, Acute
;
Lymphoma
;
Multiple Myeloma

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