Evaluation of the Self-Testing Blood Glucose Monitoring System GlucoDr.S According to ISO 15197:2013 Guidelines

BACKGROUND: The performance of the self-monitoring of blood glucose in patients with diabetes should be properly evaluated to ensure strict glycemic control. This study evaluated the self-testing Blood Glucose Monitoring System GlucoDr.S™ (All Medicus Co., Ltd., Korea). METHODS: This study recruited 120 patients. Use of the glucometer was evaluated according to ISO 15197:2013 guidelines. The YSI 2300 STAT PLUS Glucose Analyzer (YSI Life Sciences, USA) was used as the reference device. RESULTS: The standard deviation and coefficients of variation ranges for measurement repeatability and intermediate measurement precision conducted with 10 meters and 3 reagent lots on the same day were 2.7–3.2 mg/dL (0.99. The influence effect of hematocrit and the 24 interference agents was not significant, except for xylose. A system accuracy test was conducted with 100 subjects taking duplicate measurements from each of the 3 reagent lots. When glucose levels were 95% of the samples were within ±15 mg/dL and within ±15% of the average measured values of the reference measurement, respectively. In Consensus Error grid analysis, all results were distributed in zone A and B. The results of the user performance evaluation using 115 lay persons were also included in the acceptance range. CONCLUSION: The GlucoDr.S™ showed acceptable performance according to the ISO 15197:2013 guidelines and could be a clinically useful self-testing glucometer.

Performance Evaluation of a Point-of-care Test, ‘Samsung LABGEO PA CHF Test’, for the Amino-terminal Pro-brain Natriuretic Peptide

BACKGROUND: The amino-terminal pro-brain natriuretic peptide (NT-proBNP) is a useful biomarker for the diagnosis of acute congestive heart failure. A point-of-care test (POCT) could rapidly detect the presence of NT-proBNP during emergencies. We evaluated the analytical performance of the new Samsung LABGEO PA CHF Test (Samsung Electronics, Korea). METHODS: Based on the guidelines of the Clinical and Laboratory Standards Institute (CLSI), we compared the precision, linearity, and method with those of the E170 (Roche Diagnostics, Switzerland). Matrix comparison between the NT-proBNP values in whole blood and plasma was also performed, and the reference interval was determined using residual samples from healthy adults selected based on the evaluation criteria. RESULTS: The Samsung LABGEO PA CHF Test provided results in approximately 18 min. The coefficient of variation (CV) of within-laboratory precision was below 6.8%. A desirable linearity was observed in the range of 0–10,000 pg/mL, with R²=0.99. The correlation with E170 was also excellent (N=108, r=0.96). NT-proBNP values in the whole blood were correlated with those in the plasma (N=36, r=0.99). The reference interval for the circulating NT-proBNP concentration was determined in 118 plasma samples from healthy subjects (26-75 yr of age). The 97.5th percentile was found to be 58.3 pg/mL. CONCLUSIONS: The Samsung LABGEO PA CHF Test demonstrated a good analytical performance. It could be a powerful tool as a POCT for clinical practice, particularly during emergencies.

Effects of Pyridoxal-5'-Phosphate on Aminotransferase Activity Assay

BACKGROUND: Pyridoxal-5'-phosphate (P5P), a coenzyme of the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) reactions, is required to measure aminotransferase levels (IFCC method). However, a modified IFCC method that uses a reagent devoid of P5P is commonly used in laboratories in Korea. To determine the differences between the two methods, we compared aminotransferase levels measured by using the IFCC method and modified IFCC method. METHODS: Serum levels of AST and ALT, with and without P5P, were measured in 2,318 patients. Based on the allowable limits of performance set by the Royal College of Pathologists of Australasia (RCPA), differences between the two methods were analyzed under various conditions. RESULTS: Higher AST and ALT values were obtained by the IFCC method compared to modified IFCC method, showing significant differences between the two methods (AST, 5.8±14.2 IU/L; ALT, 2.8±6.9 IU/L) (P<0.001). Values exceeding RCPA criteria were more frequently observed in emergency orders (AST, 65.8%; ALT, 14.4%) than in routine orders (AST, 3.2%; ALT, 9.6%), as well as in inpatient wards (AST, 70.4%; ALT, 18.5%) compared to outpatient clinics (AST, 56.6%; ALT, 10.0%). However, the differences between the two methods were not significant among the disease groups, except for the acute myocardial infarction group. CONCLUSIONS: The method using reagents without P5P underestimated aminotransferase activity. The effect of P5P was more significant in patients with acute myocardial infarction, considered as P5P-deficient. In conclusion, the IFCC method with P5P should be applied for measuring AST and ALT serum levels.

Annual Report on the External Quality Assessment Scheme for Blood Bank Tests in Korea (2015)

We report here the results of the external quality assessment scheme (EQA) of blood bank tests in Korea carried out in 2015. The proficiency testing specimens used in the survey were prepared at Ajou University Hospital. The response rates from participating laboratories for the first and second trials were 98.7% (542/549) and 98.2% (544/554), respectively. No answers to tests were considered incorrect, and the average accuracy rates for six different test items on the standard survey were as follows: ABO grouping, 99.4% to 100.0%; RhD typing, 99.4% to 100.0%; crossmatching, 93.6% to 99.0%; direct antiglobulin test (DAT) using a polyspecific reagent, 92.9% to 98.3%; DAT using an IgG monospecific reagent, 94.6% to 100.0%; DAT using a C3d monospecific reagent, 84.2% to 98.6%; unexpected antibody screening test, 94.5% to 100.0%; and antibody identification test, 93.8% to 100.0%. We performed a pilot survey on reactivities to A1 (54 responses) and H (50 responses); Rh C, c, E, and e antigen testing (47 responses); and ABO antibody titration (10-34 responses). We obtained excellent results for this EQA, and these results will be helpful for improving or maintaining the quality of the participating laboratories.

Annual Report on the External Quality Assessment Scheme for Clinical Chemistry in Korea (2015)

The Clinical Chemistry Subcommittee of the Korean Association for External Quality Assessment Service conducted external quality assessments in 2015. This included general chemistry and blood gas measurements as part of a scheme of six trials, comprising three samples each. All control materials were included at the same time. The overall response rates were 94.4% for general chemistry and 92.2% for blood gas. The parameters tested included sodium, potassium, chloride, blood urea nitrogen, glucose, calcium, phosphorus, uric acid, creatinine, bilirubin, total protein, albumin, total cholesterol, triglyceride, aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase, lactate dehydrogenase, gamma glutamyl transferase, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol for general chemistry, and pH, partial pressure of carbon dioxide (pCO₂), and partial pressure of oxygen (pO₂) for blood gas assessments. Two types of reports were generated: a method summary, including mean, standard deviation, and coefficient of variation for each test method; and a result summary of each participating laboratory, including mean, standard deviation, number of peer groups, and standard deviation index and variance index scores of each laboratory. The overall quality performance in 2015 was similar to that of previous years, and showed lower interlaboratory variation than that in 2014. The requisite continual improvement in clinical chemistry testing quality can be achieved through participation in similar proficiency testing programs.

Six Years' Experience of Accuracy-Based Proficiency Testing for HbA1c in Korea

BACKGROUND: The proficiency testing (PT) program for HbA1c, performed by the Korean Association of External Quality Assessment Service (KAEQAS), first started in 2007. From 2007 to 2008, the results were assessed using means as the standard within a peer group (identical method group). However, the assessment method changed to accuracy-based PT in 2009. This study aimed to analyse the results of an external quality assessment of HbA1c from 2009 to 2014. METHODS: Based on the data obtained from the external quality assessment of HbA1c from 2009 to 2014, we analysed the number of participating institutions, response rate, 'unacceptable' result rate, bias from the target value, and CVs according to each instrument code. RESULTS: The number of participating institutions was only 180 in 2009. However, it increased over the next 5 years, and as of 2014, 345 institutions were enrolled. The response rates were 93.8% to 99.1%. Since 2009, the measurement method changed and most of the participating institutions now use the high-performance liquid chromatography (HPLC) method. As of 2014, the HPLC method showed small bias from the target value and inter-laboratory CVs (<3.5%), demonstrating satisfactory performance. Immunoassays and point-of-care testing (POCT) demonstrated relatively unsatisfactory performance, showing larger inter-laboratory CVs compared to those obtained with the HPLC method, with some of them exceeding the acceptance limit of +/-8% of the target value. CONCLUSIONS: As of 2014, relatively large-scale laboratories are participating in the accuracy-based PT for HbA1c. According to the accuracy-based PT for HbA1c, POCT showed the highest 'unacceptable' rate and imprecision. Therefore, small-scale laboratories mostly using POCT for HbA1c measurement should be encouraged to participate in the accuracy-based PT program for HbA1c, and the external quality assessment program undertaken by KAEQAS should be expanded.

Annual Report on the External Quality Assessment Scheme for Blood Blank Tests in Korea (2014)

We report here the results of surveys on external quality assessment (EQA) of blood bank tests in Korea carried out in 2014. The proficiency testing specimens were prepared at Ajou University Hospital and the response rates for the 1st and 2nd trials were 94.3% (537/549) and 96.0% (545/554), respectively. No answers were considered incorrect, and the average accuracy rates of six different test items on the regular survey were as follows: ABO grouping, 98.5% to 100.0%; RhD typing, 98.1% to 99.4%; crossmatching, 91.2% to 99.6%; direct antiglobulin test (DAT) using a polyspecific reagent, 96.7% to 98.4%; DAT using an immunoglobulin-G monospecific reagent, 93.8% to 98.7%; DAT using a C3d monospecific reagent, 89.5% to 98.7%; unexpected antibody screening test, 96.2% to 100.0%; and antibody identification test, 69.8% to 100.0%. Test items for the pilot survey were reactivities to anti-A1 and anti-H, Rh subgrouping, and ABO antibody titration. Except for the result of the antibody identification test for specimens with multiple antibodies, we obtained excellent survey results for the EQA of blood bank tests carried out in 2014. In addition, the number of participating institutes was higher in 2014 than in 2013. The EQA of blood bank tests in 2014 should be helpful for improving the quality of the participating laboratories.

Annual Report on External Quality Assessment of Blood Bank Tests in Korea (2013) / 임상검사와정도관리

We report here the results of surveys for External Quality Assessment (EQA) of blood bank tests carried out in 2013. The proficiency testing specimens were prepared at Ajou University Hospital and sent to 548 and 545 institutes participating in the 1st and 2nd trial, respectively. Test items for the surveys were ABO grouping, RhD typing, crossmatching, direct antiglobulin test (DAT), antibody screening test, and antibody identification test. The response rates for the 1st and 2nd trials were 94.3% and 96.0%, respectively. No answers were considered incorrect answers, and the average accuracy rates of different test items of the survey were as follows: ABO grouping, 98.9% to 100%; RhD typing, 98.4% to 99.2%; crossmatching, 94.4% to 100.0%; DAT using polyspecific reagent, 94.5% to 99.7%; DAT using IgG monospecific reagent, 94.7% to 98.8%; DAT using C3d monospecific reagent, 91.3% to 98.6%; unexpected antibody screening test, 90.9% to 100%; and antibody identification test, 87.3% to 100.0%. Overall, we obtained excellent survey results for the EQA of blood bank tests carried out in 2013, and the number of participating institutes was higher in 2013 than in 2012.

Annual Report on External Quality Assessment in Urinalysis in Korea (2009) / 임상검사와정도관리

Three external quality assesment trials which composed of 16 control materials(12 chemical materials and four sets of microscopic photograph of urinary sediment) for interlaboratory quality control assesment in urinalysis were performed with 796, 823, and 841 participants, in each, in the year of 2009. The response rate were 97.1% (796/820), 95.5% (823/862) and 97.1% (841/866), in the first, the second and the third trials, in each. The test items include pH, glucose, protein, ketone, bilirubin, blood, urobilinogen, nitrite, leukocyte estrase, specific gravity and four microscopic photographs of urinary sediment. The survey results are summarized as follows: 1. The chemical quality control test in urinalysis revealed generally good concordance. 2. The percentage of using urinalysis analyzer was slightly decreased as 82.3% and the distribution of using reagent strip was similar to the previous year. 3. The percentage of response rate of microscopic photographs of urinary sediment was 83.5% (702/841) and the percentage of good performance of these tests ware 83.6% to 99.1%.

Annual Report on External Quality Assessment in Hematology in Korea (2009) / 임상검사와정도관리

Four trials of external quality assessment in diagnostic hematology were performed in 2009 with average 946 participating laboratories in Korea. We performed quality assessment for white blood cell count, hemoglobin, hematocrit, red blood cell count, platelet count, blood cell morphology, prothrombin time and activated partial thromboplastin time. The response rate was more than 98.2%. The coefficients of variation in hemoglobin, hematocrit and RBC count were stable but variable in platelet count and WBC count according to measuring cell counters. Test results of blood cell morphology showed variation among various cell morphologies.

Cutoff Value of 17-Hydroxyprogesterone Screening Test for Congenital Adrenal Hyperplasia According to Birth Weight / 임상검사와정도관리

BACKGROUND: False positive rate of 17-OHP screening test was higher more than other screening tests due to use same cutoff value both term and preterm infants in Korea. The purpose of this study is to set cutoff value of 17-OHP on the basis of birth weight in neonatal screening for congenital adrenal hyperplasia. METHODS: 17-OHP was measured in filter paper blood spots obtained by heel puncture between 3 and 7 days after birth. 17-OHP values were analyzed with respect to birth weight in order to decide the appropriate cutoff values in a neonatal screening for congenital adrenal hyperplasia. RESULTS: The mean concentrations of 17-OHP according to birth weight groups were as follows : 12.6, 7.0, 5.1, 3.7, 3.0, 2.5 ng/mL for birth weight of 1.50 or less, 1.50-1.99, 2.00-2.49, 2.50-2.99, 3.00-3.49, 3.50 kg or more, respectively. The cutoff values for determining the 17-OHP for recall were decided as follows : 55, 35, 18, 11, 8, 8 ng/mL for birth weight of 1.50 or less, 1.50-1.99, 2.00-2.49, 2.50-2.99, 3.00-3.49, 3.50 kg or more, respectively. Application of the new cutoff values according to birth weight dropped the total recall rate from 3.3% to 1.0%. CONCLUSIONS: The cutoff values of 17-OHP on the basis of birth weight should be used in the neonatal screening for congenital adrenal hyperplasia. We believe that the recall rate due to false positive can be reduced using this method in low birth weight infants.

Annual Report on External Quality Assessment in Urinalysis in Korea (2008) / 임상검사와정도관리

Three external quality assesment trials which composed of 16 control materials (12 chemical materials and four sets of microscopic photograph of urinary sediment) for interlaboratory quality control assesment in urinalysis were performed with 699, 718, and 732 participants, in each, in the year of 2008. The response rate were 95.4% (699/733), 96.6% (718/743) and 95.3% (732/767), in the first, the second and the third trials, in each. The test items include pH, glucose, protein, ketone, bilirubin, blood, urobilinogen, nitrite, leukocyte estrase, specific gravity and four microscopic photographs of urinary sediment. The survey results are summarized as follows: 1. The chemical quality control test in urinalysis revealed generally good concordance. 2. The percentage of using urinalysis analyzer was slightly decreased as 83.0% and the distribution of using reagent strip was similar to the previous year. 3. The percentage of response rate of microscopic photographs of urinary sediment was 81.3% (571/732) and the percentage of good performance of these tests ware 32.9% to 80.5%.

Annual Report on External Quality Assessment in Hematology in Korea (2008) / 임상검사와정도관리

Four trials of external quality assessment in diagnostic hematology were performed in 2008 with average 822 participating laboratories in Korea. We performed quality assessment for white blood cell count, hemoglobin, hematocrit, red blood cell count, platelet count, blood cell morphology, prothrombin time and activated partial thromboplastin time. The response rate was more than 96.5%. The coefficients of variation in hemoglobin, hematocrit and RBC was stable but variable in platelet count and WBC count according to measuring cell count. Test results of blood cell morphology showed variation among various cell morphologies.

Microwave stimulated iron staining of plastic embedded bone marrow section / 대한임상병리학회지

No abstract available.

Effects of citrate pyridoxal 5'-phosphate-TRIS(CPT) antivoagulant on spurious low platelet counts caused by EDTA / 대한혈액학회지

No abstract available.

Microwave stimulated staining of bone marrow aspiration smears and plastic embedded section / 대한혈액학회지

No abstract available.