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Objective@#Patients presenting with fingertip skin defect injuries without exposed bone can avail of two treatment options at the emergency department (ED). This study compared outcomes between dressing and composite graft (CG) using skin stump for patients visiting the ED with fingertip skin defect injuries without exposed bone. @*Methods@#This was a single-center, retrospective, observational study. We reviewed 244 patients with fingertip skin defect injuries without exposed bone who visited the ED from September 2018 to February 2021. We compared the outcomes of the patients who were treated by CG using skin stump and those who received a dressing in the ED. @*Results@#In all, 142 patients were treated by CG using skin stump, and 102 patients were given a dressing only. In the CG group, good outcomes were obtained in 140 patients, whereas additional skin graft treatment was required for two patients with bad outcomes. In the dressing group, 81 patients had good outcomes and 21 patients had bad outcomes which required additional skin graft treatment. @*Conclusion@#Results of our study revealed that compared to traditional dressing, ED treatment for fingertip skin defects without exposed bone showed good outcomes when administered CG using skin stump. Hence, we recommend that instead of simple dressing, CG using skin stump is the preferred mode of treatment for patients presenting in the ED with fingertip skin defect injuries without exposed bone.
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The current guidelines for therapeutic drug monitoring (TDM) of vancomycin suggest a target 24-hour area under the curve (AUC 0-24 ) of 400 to 600 mg*h/L for serious methicillinresistant Staphylococcus aureus infections. In this study, the predictabilities of acute kidney injury (AKI) of various TDM target parameters, target levels, and sampling methods were evaluated in patients who underwent TDM from January 2020 to December 2020. The AUC 0-24 and trough values were calculated by both one- and two-point sampling methods, and were evaluated for the predictability of AKI. Among the AUC 0-24 cutoff comparisons, the threshold value of 500 mg*h/L in the two sampling methods was statistically significant (P = 0.042) when evaluated for the predictability of AKI. Analysis by an receiver operating characteristic curve estimated an AUC 0-24 cutoff value of 563.45 mg*h/L as a predictor of AKI, and was proposed as the upper limit of TDM target.
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), is a type of human coronavirus that causes severe pneumonia, similar to SARS-CoV-1 and Middle East respiratory syndrome coronavirus. In Korea, the SARS-CoV-2 testing has started quickly from February 2020 to respond to the COVID-19 pandemic. In this article, I would like to introduce the characteristics of coronavirus and PCR test methods that play a large role in COVID-19 quarantine measures. Real-time reverse transcription (RT)-PCR is one of the molecular diagnostic method, and it detect SARS-CoV-2 RNA by amplifying SARS-CoV-2 specific RdRp(RNA-dependent RNA polymerase) gene and E (envelope) gene at the same time. Real-time RT-PCR is currently the most reliable test that confirming COVID-19 and is in use worldwide. Real-time RT-PCR test is recommended for COVID-19 confirmatory diagnosis in Korea, but this test requires dedicated equipment, reagents, experienced technicians and laboratory medicine specialists, and it takes about a few hours to a day to report. Rapid molecular testing results in one to two hours with a simple procedure. Antigen test is less sensitive than real-time RT-PCR and can only be used as a secondary role of diagnosis. As the global COVID-19 pandemic progresses, diagnostic testing guidelines and recommendations may vary and will be updated as scientific evidence and experience of the COVID-19 accumulates.
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Background@#Although electrocardiography and cardiac troponin play important roles in the diagnosis of acute coronary syndrome (ACS), there remain unmet clinical needs. Heart-type fatty acid-binding protein (H-FABP) has been identified as an early diagnostic marker of acute myocardial infarction (AMI). In this study, we examined the diagnostic and prognostic value of H-FABP in patients suspected with ACS. @*Methods@#We conducted an observational single-center cohort study, including 89 adults aged 30 years or older, who presented to the emergency room (ER) within 24 hours after the onset of chest pain and/or dyspnea. We performed laboratory analysis and point-of-care testing (POCT) for cardiac markers, including H-FABP, troponin I, and creatine kinasemyocardial band. We also evaluated the correlation between cardiac markers and left ventricular (LV) dysfunction and extent of coronary artery disease (CAD). @*Results@#In patients presented to ER within 4 hours after symptom onset (n = 49), the diagnostic accuracy of H-FABP for AMI, as quantified by the area under the receiver operating characteristic curve, was higher (0.738; 95% confidence interval [CI], 0.591–0.885) than other cardiac markers. In POCT, the diagnostic accuracy of H-FABP (56%; 95% CI, 45–67) was significantly higher than other cardiac markers. H-FABP was correlated with not extent of CAD but post-AMI LV dysfunction. @*Conclusion@#H-FABP is a useful cardiac marker for the early diagnosis of AMI and prediction of myocardia injury. Difference in the circulatory release timeline of cardiac markers could explain its utility in early-stage of myocardial injury.
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), is a type of human coronavirus that causes severe pneumonia, similar to SARS-CoV-1 and Middle East respiratory syndrome coronavirus. In Korea, the SARS-CoV-2 testing has started quickly from February 2020 to respond to the COVID-19 pandemic. In this article, I would like to introduce the characteristics of coronavirus and PCR test methods that play a large role in COVID-19 quarantine measures. Real-time reverse transcription (RT)-PCR is one of the molecular diagnostic method, and it detect SARS-CoV-2 RNA by amplifying SARS-CoV-2 specific RdRp(RNA-dependent RNA polymerase) gene and E (envelope) gene at the same time. Real-time RT-PCR is currently the most reliable test that confirming COVID-19 and is in use worldwide. Real-time RT-PCR test is recommended for COVID-19 confirmatory diagnosis in Korea, but this test requires dedicated equipment, reagents, experienced technicians and laboratory medicine specialists, and it takes about a few hours to a day to report. Rapid molecular testing results in one to two hours with a simple procedure. Antigen test is less sensitive than real-time RT-PCR and can only be used as a secondary role of diagnosis. As the global COVID-19 pandemic progresses, diagnostic testing guidelines and recommendations may vary and will be updated as scientific evidence and experience of the COVID-19 accumulates.
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Background@#Although electrocardiography and cardiac troponin play important roles in the diagnosis of acute coronary syndrome (ACS), there remain unmet clinical needs. Heart-type fatty acid-binding protein (H-FABP) has been identified as an early diagnostic marker of acute myocardial infarction (AMI). In this study, we examined the diagnostic and prognostic value of H-FABP in patients suspected with ACS. @*Methods@#We conducted an observational single-center cohort study, including 89 adults aged 30 years or older, who presented to the emergency room (ER) within 24 hours after the onset of chest pain and/or dyspnea. We performed laboratory analysis and point-of-care testing (POCT) for cardiac markers, including H-FABP, troponin I, and creatine kinasemyocardial band. We also evaluated the correlation between cardiac markers and left ventricular (LV) dysfunction and extent of coronary artery disease (CAD). @*Results@#In patients presented to ER within 4 hours after symptom onset (n = 49), the diagnostic accuracy of H-FABP for AMI, as quantified by the area under the receiver operating characteristic curve, was higher (0.738; 95% confidence interval [CI], 0.591–0.885) than other cardiac markers. In POCT, the diagnostic accuracy of H-FABP (56%; 95% CI, 45–67) was significantly higher than other cardiac markers. H-FABP was correlated with not extent of CAD but post-AMI LV dysfunction. @*Conclusion@#H-FABP is a useful cardiac marker for the early diagnosis of AMI and prediction of myocardia injury. Difference in the circulatory release timeline of cardiac markers could explain its utility in early-stage of myocardial injury.
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External quality assessment (EQA) is important for evaluating clinical laboratories and enhancing their testing quality. EQA schemes are variable; thus, it is crucial that the EQA organizers share their experiences to continuously improve the EQA scheme. The Korean Association of External Quality Assessment Service (KEQAS) has been the leading, authorized EQA institute for the standardization and quality management of laboratory testing in Korean medical institutions since 1976. The EQA scheme underwent a major change in 2016, and the number of EQA programs increased significantly since then. The key changes implemented in EQA scheme include a fully computerized assessment to accelerate feedback and unification of the testing and reporting methods. We provide an overview of the EQA schemes and performance evaluation criteria of the KEQAS and suggest directions for achieving the global harmonization of EQA.
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Background@#Total cholesterol concentration measurement is important in the diagnosis of dyslipidemia and evaluation of cardiovascular disease risk factors. Measurement reliability for obtaining an accurate total cholesterol concentration requires procedure standardization. We evaluated the standardization status for total cholesterol concentration measurement through Korean external quality assessment (EQA) data analysis. @*Methods@#This study involved 1,670 laboratories that participated in the EQA of total cholesterol concentration measurements in 2019 for 32 products from different manufacturers. The target concentrations of three quality control (QC) materials (samples A, B, and C) were measured using the reference method and compared with EQA data. The performance criteria for total cholesterol concentration measurement were based on the National Cholesterol Education Program guidelines, with ± 3% inaccuracy. @*Results@#The target values and inaccuracies of the QC material based on the reference method measurements were 254.65 ± 7.64, 108.30 ± 3.25, and 256.29 ± 7.69 mg/dL (6.59 ± 0.20, 2.80 ± 0.08, and 6.63 ± 0.20 mmol/L) for samples A, B, and C, respectively.The performance criteria were not met in 42.7% laboratories for sample A, 68.4% of laboratories for sample B, and 38.0% laboratories for sample C. @*Conclusions@#Despite significant efforts to accurately measure total cholesterol concentrations, further actions are needed for measurement standardization. Manufacturers reporting values that differ from target values should check calibrator traceability; additional efforts to accurately measure total cholesterol concentrations are required for laboratories that use products from these manufacturers.
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Background@#Accurate serum creatinine (Cr) concentration measurement is essential for evaluating kidney function. In 2011, the Korean Association of External Quality Assessment Service (KEQAS) launched an accuracy-based Cr proficiency testing (ABCr PT) survey. We analyzed long-term data of the KEQAS ABCr PT survey collected between 2011 and 2019 to assess recent trends in Cr assays in Korea. @*Methods@#The ABCr PT survey including three commutable fresh-frozen serum samples was performed twice a year. The target Cr concentration was assigned using isotope-dilution mass spectrometry. We analyzed data obtained from the participating laboratories, calculated the yearly bias, and evaluated bias trends for the major reagents and instruments. Outliers were excluded from all analysis. @*Results@#The mean percentage bias based on the total data of all participating laboratories was 10.8% in the 2011-A survey and 0.2% in 2019-B survey. Bias for the major reagents and instruments differed depending on the manufacturer. Enzymatic assays generally showed desirable bias ranging from –3.9% to 3.2% at all Cr concentrations and lower interlaboratory variability than non-enzymatic assays (enzymatic vs. non-enzymatic, 3.3%– 7.2% vs. 6.3%–9.1%). @*Conclusions@#Although the mean percentage bias of Cr assays tends to decrease over time, it is necessary to continuously strive to improve Cr assay accuracy, especially at low concentrations.
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The use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) in clinical laboratories is increasing and is likely to expand into even more clinical venues in the future. Mass spectrometry is the standard method for analyte identification in the clinical chemistry field; however, differences in mass spectrometry protocols and handling affect the accuracy and reliability of these tests and prevent direct comparisons of results between laboratories. For example, the results of laboratories using LC-MS/MS methods are less likely to be reproducible than those of laboratories using conventional, automated methods. This is due to inadequate handling of the equipment and/or poor quality control after the implementation of the method, which may result in unnecessary medical expenditures or even adverse outcomes for the patients. Unfortunately, guidelines to monitor the accuracy of LC-MS/MS-based clinical tests are still lacking. In general, the quality control methods used in conventional clinical tests could also be applied to LC-MS/MS. However, additional quality control methods specific to LC-MS/MS techniques must be continuously employed to maintain the same quality level achieved during method development and verification. This report is intended to help clinical laboratories that operate LC-MS/MS improve the accuracy and reliability of their testing by providing guidance for quality assurance and improvement, based on a collection of existing guidelines and expert opinions from the literature.
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Background@#For effective management of blood components, periodic updates of the maximum surgical blood order schedule (MSBOS) using recent data are crucial. This study aimed to establish an updated MSBOS and red blood cell (RBC) mean transfusion units per patient according to the adjacent diagnosis related groups (ADRG) classification system. @*Methods@#This retrospective study was based on an audit of the medical records of inpatients at a tertiary hospital between January and December 2017. We investigated transfusion-related data to establish the MSBOS and determine the RBC mean transfusion units per patient according to the ADRG and compared these updated values with previous data. @*Results@#During the investigated period, a total of 5,607 RBC units were transfused in 17,382 patients. The revised MSBOS was similar to the previous MSBOS in most surgeries. Among the 130 ADRG codes analyzed, 34 codes showed an increase, while 96 codes showed a decrease in RBC mean transfusion units per patient, compared to data from 2007. Overall, the RBC mean transfusion units per patient in 2017 was 0.89 units less compared to that in 2007 after adjusting for age (95% CI: 0.853–0.912). @*Conclusions@#The revised MSBOS was similar to that of the previous versions. However, there were differences in the number of RBC transfusion units used in some surgeries and disease treatments compared to those in the past. Considering the changes within the medical environment, this study highlights the importance of periodic evaluation of MSBOS and RBC transfusion usage.
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Cross-reactive carbohydrate determinants (CCDs) are simple carbohydrates linked to amino acid chains; they are found in pollens, vegetable foods, insect, and Hymenoptera venoms and are broadly cross-reactive with CCD-specific IgE antibodies. A man in his fifties was evaluated using a multiple allergen simultaneous test–immunoblot assay. On the PROTIA Allergy-Q 64 inhalant panel (ProteomeTech, Korea), reactions to 37 of 59 antigens were observed except mammalian antigens, and cross-reactivity owing to anti-CCD antibodies was suspected. After ProGlycAn CCD-blocker (ProGlycAn, Austria) treatment, the patient exhibited no response to CCD allergens, and the number of allergens showing positive reactions was reduced to 15. We further tested a total of 7 samples from patients who were suspected to have CCD-related cross-reactivity. For these 8 patients, the average number of positive reactions to allergens was reduced from 33 (range 24-36) to 8 (range 0-19) after CCD-blocker treatment. We concluded that CCD-blocker treatment in sample with anti-CCD antibodies can reduce the false positive reponse and provide more specific information about allergens.
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Subject(s)
Humans , Immunoassay , Indicators and Reagents , Mass Spectrometry , Methods , Pathology, Molecular , Spectrum AnalysisABSTRACT
BACKGROUND: Differences in the performance of suggested warfarin dosing algorithms among different ethnicities and genotypes have been reported; this necessitates the development of an algorithm with enhanced performance for specific population groups. Previous warfarin dosing algorithms underestimated warfarin doses in VKORC1 1173C carriers. We aimed to develop and validate a new warfarin dosing algorithm for Korean patients with VKORC1 1173C.METHODS: A total of 109 patients carrying VKORC1 1173CT (N=105) or 1173CC (N=4) were included in this study. Multiple regression analysis was performed to deduce a new dosing algorithm. Following literature searches for genotype-guided warfarin dosing algorithms, 21 algorithms were selected and evaluated using the correlation coefficient (ρ) of actual dose and estimated dose, mean error, and root mean square error.RESULTS: The developed algorithm is as follows: maintenance dose (mg/week)=exp [3.223−0.009×(age)+0.577×(body surface area [BSA])+0.178×(sex)−0.481×(CYP2C9 genotype)+0.227×(VKORC1 genotype)]. Integrated variables explained 44% of the variance in the maintenance dose. The predicted and actual doses showed moderate correlation (ρ=0.641) with the best performance with a mean error of −1.30 mg/week. The proportion of underestimated groups was 17%, which was lower than with the other algorithms.CONCLUSIONS: This is the first study to develop and validate a warfarin dosing algorithm based on data from VKORC1 1173C carriers; it showed superior predictive performance compared with previously published algorithms.
Subject(s)
Humans , Genotype , Korea , Population Groups , WarfarinABSTRACT
Genetic hemoglobin disorders are caused by mutations and/or deletions in the α-globin or β-globin genes. Thalassemia is caused by quantitative defects and hemoglobinopathies by structural defect of hemoglobin. The incidence of thalassemia and hemoglobinopathy is increased in Korea with rapid influx of people from endemic areas. Thus, the awareness of the disease is needed. α-thalassemias are caused by deletions in α-globin gene, while β-thalassemias are associated with decreased synthesis of β-globin due to β-globin gene mutations. Hemoglobinopathies involve structural defects in hemoglobin due to altered amino acid sequence in the α- or β-globin chains. When the patient is suspected with thalassemia/hemoglobinopathy from abnormal complete blood count findings and/or family history, the next step is detecting hemoglobin abnormality using electrophoresis methods including high performance liquid chromatography and mass spectrometry. The development of novel molecular genetic technologies, such as massively parallel sequencing, facilitates a more precise molecular diagnosis of thalassemia/hemoglobinopathy. Moreover, prenatal diagnosis using genetic testing enables the prevention of thalassemia birth and pregnancy complications. We aimed to review the spectrum and classification of thalassemia/hemoglobinopathy diseases and the diagnostic strategies including screening tests, molecular genetic tests, and prenatal diagnosis.
Subject(s)
Humans , Amino Acid Sequence , Anemia , Blood Cell Count , Chromatography, Liquid , Classification , Clinical Laboratory Techniques , Diagnosis , Electrophoresis , Erythrocytes , Genetic Testing , Hematology , Hemoglobinopathies , High-Throughput Nucleotide Sequencing , Incidence , Korea , Mass Screening , Mass Spectrometry , Molecular Biology , Parturition , Pregnancy Complications , Prenatal Diagnosis , ThalassemiaABSTRACT
The Clinical Mass Spectrometry Research Committee (CMSRC), in affiliation with the Korean Society of Clinical Chemistry (KSCC), conducted a questionnaire survey on opinions about the general status of clinical mass spectrometric analysis in Korea. As a result, we understand that this field has passed through the introductory stage and is settled as a field of clinical laboratory testing in Korea, with the number of new laboratories performing mass spectrometric analysis being low. In spite of the many difficulties in introducing and operating clinical mass spectrometric analysis, there is a strong interest in this field, and even though further expansion is expected, there are still many issues to be resolved. In the future, it will be necessary to make concrete and thorough efforts to further develop the laboratory tests using clinical mass spectrometric analysis in Korea, centering on the CMSRC affiliated with the KSCC.
Subject(s)
Chemistry, Clinical , Korea , Mass SpectrometryABSTRACT
BACKGROUND: Blood culture is an important method for identifying infectious microorganisms and confirming that a selected antimicrobial treatment is appropriate. In this study, we investigated the annual changes in the frequencies of blood isolates and antibiotic susceptibility test (AST) results. METHODS: We created a large database comprising data on all patient-unique blood cultures obtained from January 2007 through December 2016. Blood specimens were cultured using the BD BACTEC FX system, and species identification and AST were performed using the VITEK 2 system. RESULTS: During the 10-year study period, a total of 203,651 blood culture results were collected. Of these, gram-positive cocci, gram-negative rods, and fungi were isolated in 2.15%, 0.55%, and 0.12% of the blood cultures, respectively. Escherichia coli was the most commonly isolated species (22.8%), followed by Staphylococcus epidermidis (16.8%), Klebsiella pneumoniae (8.1%), and Staphylococcus aureus (8.0%). Fungal species were isolated in 3.0% of all positive blood cultures. Candida albicans was the most commonly isolated species (1.1%), followed by Candida parapsilosis (0.6%). Methicillin resistance was seen in 55.2% of S. aureus isolates. The frequencies of vancomycin-resistant Enterococcus (VRE) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) were 13.1% and 10.9%, respectively. The isolation rates of MRSA, VRE, and CRPA showed different patterns each year. CONCLUSIONS: Among the isolates, E. coli was the most common, followed by S. epidermidis and K. pneumoniae. This study represents a long-term analysis of bloodstream infections, and the results can be used to identify trends in the microorganisms isolated and their drug resistance.
Subject(s)
Bacteremia , Candida , Candida albicans , Drug Resistance , Enterococcus , Escherichia coli , Fungi , Gram-Positive Cocci , Klebsiella pneumoniae , Korea , Methicillin Resistance , Methicillin-Resistant Staphylococcus aureus , Methods , Pneumonia , Pseudomonas aeruginosa , Staphylococcus aureus , Staphylococcus epidermidisABSTRACT
BACKGROUND: Standardization of creatinine assay is consistently performed and much effort has been put into improving the accuracy of the results. We aimed to analyze the results of accuracy-based proficiency testing of creatinine assays performed by the Korea Association of External Quality Assessment Service from 2011 to 2017 to assess the current state of creatinine assays in Korea. METHODS: From 2011 to 2017, the accuracy-based proficiency testing of creatinine was performed twice a year. We analyzed the results obtained from the participating laboratories and calculated the year-wise bias. The acceptable limit of bias was as follows: ±11.4% for creatinine concentration >1.0 mg/dL, and 0.114 mg/dL for creatinine concentration ≤1.0 mg/dL. The trend of bias with the major instruments and reagent manufacturers were analyzed. RESULTS: The number of participating laboratories was 54 in 2011, which gradually increased to 146–178 after 2015. For each of the three samples used in the survey, the percentage of laboratories whose biases in the results were within the acceptable limits was 33.3% for the first time in 2011, which gradually increased to 74.7%–85.0% after 2014. The mean biases in all the results of the participating laboratories were 11.1% in 2011 (1st trial) and 2.4% in 2017 (2nd trial). The biases in the results with the major instruments and reagents differed according to the manufacturers. CONCLUSIONS: The mean bias in the results obtained from the participating laboratories in the accuracy-based proficiency testing of creatinine surveys showed a decreasing trend.
Subject(s)
Bias , Creatinine , Indicators and Reagents , KoreaABSTRACT
As part of the clinical chemistry programs of the Korean Association of External Quality Assessment Service, we organized trials to conduct external quality assessment of hemoglobin A1c (HbA1c) in 2016 and 2017. We delivered three commutable whole blood specimens for each trial. The overall response rates were 96.4% in 2016 and 98.4% and 99.6% in the first and second trials in 2017, respectively. Two types of reports were generated: a common report including the mean, standard deviation, coefficient of variation, median, minimum value, and maximum value according to manufacturer and instrument, as well as a summary report of the results from each participating laboratory, including a histogram for each specimen, Levey-Jennings chart for serial percent deviations, and table showing the target value, upper and lower limits, percent deviation, and grade. From 2016, the acceptance criterion was changed from ±8.0% to ±6.7%. The overall acceptable rates for the survey were 91.5%, 91.4%, 94.9%, and 89.0% for the first trial in 2016 through the second trial in 2017, respectively. The requisite continual improvement in the quality of HbA1c testing can be achieved through participation in similar accuracy-based proficiency testing programs.