Extratendinous migration of calcific tendinitis of the rotator cuff: imaging findings and clinical characteristics with temporal changes.

PURPOSE: The aim of this study was to analyze the imaging findings and clinical characteristics of extratendinous migration of calcific tendinitis of the shoulder with temporal changes. METHODS: Seventy-six patients with extratendinous calcific tendinitis of the shoulder diagnosed by ultrasonography (US) or magnetic resonance imaging (MRI) were enrolled in this retrospective study. Clinical symptoms and imaging findings (on radiography, US, and MRI) of extratendinous calcific tendinitis during an acute painful attack were analyzed. Temporal changes were analyzed in 28 patients before an acute attack and 40 patients after an acute attack. For comparison, 65 patients with intratendinous calcific tendinitis were included. RESULTS: Patients with extratendinous calcific tendinitis had a significantly higher average visual analogue scale (VAS) score (8.8±1.6) than the intratendinous group (6.4±2.2) (P<0.001). The fragmented type (80.5%) was the most common shape on US; sonographic black hole appearance (14.6%) and echogenic fluid (9.8%) were characteristic findings of intrabursal calcifications. In 28 patients with previous radiographs, radiographic type III (78.6%) was dominant and the location of calcific deposits changed (82.1%) during the acute painful attack, which was also perceivable in 12 patients with previous US or MRI. In follow-up radiographs of 40 patients, calcifications shrunk by more than 50% or became invisible in 82.5% of patients, with symptom improvement (VAS score, 8.9±1.5 to 1.9±1.2). Follow-up US and MRI of 16 patients also showed decreased size (56.3%) or disappearance (43.7%) of calcific deposits. CONCLUSION: Extratendinous calcific tendinitis has distinctive imaging features, the temporal changes of which correlate well with clinical symptoms.

Analytical and Clinical Evaluation of Chemiluminescent Carcinoembryonic Antigen (CEA) by HISCL-5000 Immunoanalyzer.

OBJECTIVE: The carcinoembryonic antigen (CEA) is coupled with a diagnosis and prognosis for cancers METHODS: The analytical performance of CEA by chemiluminescent immunoassay (HISCL-5000, Sysmex, Kobe, Japan) was evaluated on the basis of precision, linearity, trueness, and method comparison. Clinical evaluation was performed by area under the receiver operating characteristic curve (AU-ROC) curve analysis for lung, stomach and colorectal cancers. RESULTS: Total coefficient of variation (CV) (5.039% to 5.632%), linearity (0.5 to 982 ng/mL) and the percentage bias by trueness verification were less than desirable specifications for imprecision (6.4%) and bias (14.3%). The regression equation was y=0.354+0.957x(r=0.968) from method comparison. AUROC for lung, stomach, and colorectal cancers compared with normal healthy control ranged from 0.908 to 0.967 (cut-off 4.50 to 4.71 ng/mL), and compared with non-malignant benign disease, ranged from 0.578 to 0.721 (cut-off 8 to 20.70 ng/mL). CONCLUSIONS: CEA by HISCL-5000 immunoassay provided reliable performance. Comorbidities should be considered for interpretation of CEA.

Analytical evaluation and clinical application of insulin and C-peptide by a whole blood, lateral flow, point of care (POC) assay system.

The analytical performance and clinical application of measuring insulin and connecting peptide (C-peptide) by point of care (POC) assay were evaluated. A POC assay system (SelexOn, Osang Healthcare Inc., Anyang-si, Korea) was evaluated for precision, linearity, limit of blank (LOB), and limit of detection (LOD). Method comparison was performed with the Cobas Elecsys insulin and C-peptide assay (Roche Diagnostics GmbH, Mannheim, Germany) using 215 and 201 patient specimens for insulin and C-peptide, respectively. For clinical application, insulin resistance indices were studied. Homeostasis model assessment (HOMA) 1 and 2, Quantitative insulin sensitivity check index (QUIKI), fasting insulin resistance index (FIRI), and other indices were evaluated. The coefficient of variation (CV) of imprecision for low, medium, and high concentrations was 10.8%1, 15.99%, and 12.05%, respectively, for insulin and 9.21%, 13.51%, and 13.77%, respectively, for C-peptide. The linearity was validated to 839.78 pmol/L for insulin and to 17.30 nmol/L for C-peptide. LOB and LOD were 8.05 and 9.72 pmol/L for insulin and 0.05 and 0.08 nmol/L for C-peptide, respectively. For the method comparison, the regression equation was y = 1.259x - 8.818 (r = 0.957) for insulin and y = 1.163x - 0.088 (r = 0.985) for C-peptide. The ROC value and overall accuracy were as follows: HOMA2 (C-peptide), 0.809, 79.7%; TyG, 0.788, 73.6%; CPR, 0.775, 74.8%; HOMA1, 0.725, 70.3%; QUIKI, 0.720, 70.3%; FIRI, 0.715, 70.1%; McAuley, 0.658, 65.1%; HOMA2 (Insulin), 0.645, 64.7%; Raynaud, 0.611, 61.4%, respectively. The POC assay system for insulin and C-peptide provided reliable results through a rapid and simple test that could be applied to clinical settings.

Development of Statistical Software for the Korean Laboratory Accreditation Program Using R Language: LaboStats.

BACKGROUND: In Korea, the Korean Laboratory Accreditation Program (KLAP) has set minimum standards for verification of clinical test performance. This verification process is time-consuming and labor-intensive when performed manually. We developed a free, statistical software program for KLAP, using the R language (R Foundation for Statistical Computing, Vienna, Austria). METHODS: We used CLSI guidelines for the algorithm. We built graphic user interfaces, including data input, with Embarcadero Delphi EX4 (Embarcadero Technologies, Inc., Texas, USA). The R Base Package and MCR Package for Method Comparison Regression were used to implement statistical and graphical procedures. RESULTS: Our program LaboStats has six modules: parallel test, linearity, method comparison, precision, reference interval, and cutoff. Data can be entered into the field either manually or by copying and pasting from an MS Excel worksheet. Users can print out precise reports. CONCLUSIONS: LaboStats can be useful for evaluating clinical test performance characteristics and preparing documents requested by KLAP.

Computed tomographic thoracic morphologic indices in normal subjects and patients with chronic obstructive pulmonary disease: Comparison with spiral CT densitometry and pulmonary function tests.

OBJECTIVES: To determine what computed tomographic (CT) dimensions can predict obstructive lung disease on routine chest CT scans by comparing morphological and densitometric CT findings with pulmonary function test (PFT) in normal subjects and patients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: Consecutive patients (n = 646; 260 females and 386 males; mean age 54.9 years, ranged 20-90 years) who received chest CT scans with densitometry during a 3-month period were retrospectively analyzed in single center. PFT was undertaken in 235 patients (152 males, 83 females) at same times of CT scanning. The patients were grouped by age (<30 years, 31-45 years, 46-60 years, and >61 years). CT parameters including tracheal, azygoesophageal, thoracic vertical, anterior-posterior (AP), transverse diameters, transverse cardiac diameter, diameters of main, right, and left pulmonary arteries, and CT densitometric values including lung volume and density (-900 to -1000 Hounsfield Units, HU), low attenuation value cluster (default threshold: -950 HU) were compared with PFT values. Spearman correlation coefficients was used to evaluate the relationship between the CT indices and PFT. RESULTS: Ninety of 235 patients with PFT were smokers (76 males, 14 females). Obstructive PFT was detected in 65 patients (27.7%: 46 males, 19 females). Male smokers with obstructive PFT displayed significantly larger thoracic anterior-posterior (mean: normal, 172.3 cm versus COPD, 185.9 cm, p = 0.0001) and smaller transverse diameters (mean: normal, 247.0 cm vs. COPD, 235.8 cm, p = 0.01), and increased right pulmonary artery diameter (mean: normal, 20.3 cm v s. COPD, 22.1 cm, p < 0.001), and increased left pulmonary artery diameter (mean: normal, 19.7 cm vs. COPD, 20.6 cm, p < 0.025). The lung parenchyma density (-1000 to -900 HU) and greater concentration of largest cluster on densitometry were significantly different between normal and obstructive PFT pattern in male smoker. Residual volume and total lung capacity are positively correlated with lung volume and lung density (-1000 to -800) of densitometry. CONCLUSIONS: CT findings of the overexpansion of the lungs, such as increases in the vertical diameter of the lung and decreases in the transverse diameter of the heart, can be significant as indirect findings of early chronic obstructive diseases. However, despite the significant CT findings in male smokers, particularly those in their 40s, most lung function parameters were not decidedly abnormal.

Utility of Reference Change Values for Delta Check Limits.

OBJECTIVES: To assess the utility of reference change values (RCVs) as delta check limits. METHODS: A total of 1,650,518 paired results for 23 general chemistry test results from June 1, 2014, to October 31, 2016, were analyzed. The RCVs for each analyte were calculated from the analytical imprecision and within-subject biological variation. The percent differences between two consecutive results in one patient were categorized into one of four groups: outpatients, inpatients, emergency care, and general health care. For each, 2.5th and 97.5th percentile values were computed and compared with their RCVs. The distributions were assessed for normality using the Kolmogorov-Smirnov test. RESULTS: Most of the estimated limits were larger than the corresponding RCVs and, furthermore, with notable differences across the groups. Patients in the emergency care group usually demonstrated larger delta percent values than those in the other groups. None of the distributions of the percent differences passed tests of normality when subjected to Kolmogorov-Smirnov analysis. CONCLUSIONS: Comparison of estimated RCVs and real-world patient data revealed the pitfalls of applying RCVs in clinical laboratories. Laboratory managers should be aware of the limitations of RCVs and exercise caution when using them.

Evaluation of a novel point-of-care test kit, ABSOGEN™ PCT, in semi-quantitative measurement of procalcitonin in whole blood.

BACKGROUND: In response to inflammation, procalcitonin plasma concentrations increase more rapidly than other acute-phase reactants and higher values are associated with severe disease. Procalcitonin measurements assist in determining whether antibiotic therapy should be used. point-of-care testing (POCT) is performed for early decision making about additional testing or therapy. The ABSOGEN™ PCT (Bumyoungbio, Inc., Suwon, Korea) is a rapid novel semi-quantitative immunochromatographic PCT assay that analyses whole blood samples. We compared the patient quantitative test results to ABSOGEN™ PCT test results. METHODS: Whole blood was loaded onto an ABSOGEN™ PCT cartridge and incubated for 10 minutes. The color intensity of the band of the cartridge was measured using an accompanying device and with the naked eye. The results were graded as negative (<0.1 ng/mL), low (0.1 to <1.0 ng/mL), middle (1.0-2.0 ng/mL), and high (>2.0 ng/mL). A total of 158 specimens with procalcitonin levels measured from 0 to 18.96 ng/mL were used for comparison study. RESULTS: The concordance rate between ABSOGEN™ PCT using the reader and quantitative assay, between ABSOGEN™ PCT using naked eyes and quantitative assay, and between ABSOGEN™ PCT using the reader and naked eyes for the same category was 83.5% (P=.040), 78.5% (P<.001), and 82.3% (P=.001), respectively. The concordance rates for the ±1 categories were all 100%. CONCLUSION: ABSOGEN™ PCT is an accurate assay. It is easy to use, simple, fast, portable. The assay has potential value in clinical applications, especially in emergency care.

Analytical Performance Evaluation of Infopia Element™ Auto-coding Blood Glucose Monitoring System for Self-Monitoring of Blood Glucose.

BACKGROUND: Element™ Auto-coding Blood Glucose Monitoring System (BGMS; Infopia Co., Ltd., Anyang-si, Korea) was developed for self-monitoring of blood glucose (SMBG). METHODS: Precision, linearity, and interference were tested. Eighty-four capillary blood samples measured by Element™ BGMS were compared with central laboratory method (CLM) results in venous serum. Accuracy was evaluated using ISO 15197:2013 criteria. RESULTS: Coefficients of variation (CVs; mean) were 2.4% (44.2 mg/dl), 3.7% (100.6 mg/dl), and 2.1% (259.8 mg/dl). Linearity was shown at concentrations 39.25-456.25 mg/l (y = 0.989 + 0.984x, SE = 17.63). Up to 15 mg/dl of galactose, ascorbic acid, and acetaminophen, interference > 10.4% was not observed. Element™ BGMS glucose was higher than CLM levels by 3.2 mg/dl (at 200 mg/dl) to 8.2 mg/dl (at 100 mg/dl). The minimum specification for bias (3.3%) was met at 140 and 200 mg/l glucose. In the Clarke and consensus error grids, 100% of specimens were within zone A and B. For Element™ BGMS values, 92.9% (78/84) to 94.0% (79/84) were within a 15 mg/dl (< 100 mg/dl) or 15% (> 100 mg/dl) of the average CLM value. CONCLUSION: Element™ BGMS was considered an appropriate SMBG for home use; however, the positive bias at low-to-mid glucose levels requires further improvement.

Evaluation of the Performance of Two Point-of-Care Analyzers for Total Cholesterol, Triglyceride, and High-Density Lipoprotein Cholesterol Analysis.

BACKGROUND: In this study, we evaluated the analytic performance of two POCT devices and compared the results with a central laboratory method. METHODS: A total of 100 patients were enrolled in this study. LipidPro (Infopia, USA) and LandMark (Infopia, Korea), were used for measuring total cholesterol (TC), triglyceride (TG), and high density lipoprotein cholesterol (HDL-C). Imprecision and linearity were assessed and the results of two POCT analyzers were compared with a central laboratory method. RESULTS: Imprecision of LipidPro met the National Cholesterol Education Program (NCEP) criteria (mean % CV: TC 2.8%, TG 3.9%, and HDL-C 4.0%). LandMark met the National Cholesterol Education Program (NCEP) imprecision criteria for TC and TG, but not HDL-C (mean % CV: 2.7%, 3.5%, and 4.7%, respectively). Both analyzers showed excellent linearity for TC, TG, and HDL-C in test ranges. Total errors of TC, TG, and HDL-C measured by LipidPro were 6.1%, 8.7%, and 8.1%, respectively, and met the NCEP goals. The total errors of TG and HDL-C measured by LandMark met the NCEP goals; however, the total error of TC analysis did not meet the NCEP goals (total error; TC 11.1%, TG 11.2%, and HDL-C 9.6%). CONCLUSIONS: LipidPro and LandMark are simple and rapid tests that provide a reliable alternative to conventional laboratory methods. The LipidPro device showed a slightly better analytical performance than LandMark based on the NCEP goals.

Novel COL9A3 mutation in a family diagnosed with multiple epiphyseal dysplasia: a case report.

BACKGROUND: Multiple epiphyseal dysplasia is a common skeletal dysplasia characterized by mild short stature, early-onset osteoarthritis mainly involving the hip and knee joints, and abnormally small and/or irregular epiphyses. Multiple epiphyseal dysplasia is clinically and genetically heterogeneous and six genes are associated with the phenotype of multiple epiphyseal dysplasia. CASE PRESENTATION: A 12-year-old Korean boy presented with intermittent knee pain. His height was 144.6 cm (20th percentile) and family history was notable for early-onset osteoarthritis in his father. The proband's x-rays revealed epiphyseal changes characteristic of multiple epiphyseal dysplasia associated with a collagen IX defect, with manifestations primarily restricted to the knees. Mutational analysis identified a novel c.104G>A substitution in exon 2 of COL9A3, resulting in p.Gly35Asp in the proband and his father. In silico analyses predicted the p.Gly35Asp amino acid change to be detelerious, and molecular dynamics simulation demonstrated a major structural change in the heterotrimeric collagen IX. CONCLUSION: So far, three COL9A3 mutations, have been reported. These three mutations are located at the splice donor or acceptor site of COL9A3 and cause skipping of exon 3, resulting in the deletion of 12 aminoacids in the COL3 domain of COL9A3. In contrast, the novel missense mutation identified in this two-generation family with multiple epiphyseal dysplasia is a missense mutation affecting the Gly residue of the Pro-Pro-Gly repeat sequence in the COL3 domain of collage IX, with accompanying major structural change of the collagen peptide.

LEGO plot for simultaneous application of multiple quality requirements during trueness verification of quantitative laboratory tests.

BACKGROUND: We developed a two-dimensional plot for viewing trueness that takes into account potential shift and variable quality requirements to verify trueness using certified reference material (CRM). METHODS: Glucose, total cholesterol (TC), and creatinine levels were determined by two kinds of assay in two levels of a CRM. Available quality requirements were collected, codified, and sorted in an ascending order in the plot's header row. Centering on the mean of measured values from CRM, the "mean ± US CLIA '88 allowable total error" was located in the header of the leftmost and rightmost columns. Twenty points were created in intervening columns as potential shifts. Uncertainties were calculated according to regression between certified values and uncertainties of CRM, and positioned in the corresponding columns. Cells were assigned different colors where column and row intersected based on comparison of the 95% confidence interval of the percentage bias with each quality requirement. RESULTS: A glucose assay failed to meet the highest quality criteria, for which shift of +0.13-0.14 mmol/l was required. A TC assay met the quality requirement and a shift of ±0.03 mmol/l was tolerable. A creatinine assay also met the quality requirement but any shift was not tolerable. CONCLUSION: The plot provides a systematic view of the trueness of quantitative laboratory tests.

The analytical performance evaluation of Freelite™ Human Kappa Free and Human Lambda Free on the SPAPLUS™ immunoturbidimetric analyzer.

BACKGROUND: SPAPLUS™ is a turbidimetric immunoassay analyzer for detection of excess free light chain (FLC) antigens in serum. Here, we evaluated the analytical performance of Freelite™ Human Kappa Free and Lambda Free on a SPAPLUS™ instrument. METHODS: We evaluated the precision, linearity, sample carryover, and drift of the SPAPLUS™ instrument and compared it with Hitachi 7600 and BN™ II instruments. We evaluated the detection of antigen excess for 12 specimens from patients with monoclonal gammopathy. RESULTS: The coefficients of variations of κFLC and λFLC were below 5.0%. Linearity was shown in the range of 9.68-152.25 mg/l for κFLC and 4.96-171.09 mg/l for λFLC, and no drift was observed. The κFLC sample carryover was statistically significant, but much smaller than the optimum allowable bias. Agreement rates with the two comparative methods were 87.1, 87.1, and 97.1% or higher for κFLC, λFLC, and the κ/λ ratio, respectively. Antigen excess signals were observed for all 12 antigen excess specimens. CONCLUSIONS: The Freelite™ on the SPAPLUS™ exhibited appropriate precision, linearity, and relative comparability to the reagents on the other instruments. It was good at detecting specimens that had previously demonstrated the hook effect due to antigen excess.

Analytical performance of a new one-step quantitative prostate-specific antigen assay, the FREND™ PSA Plus.

BACKGROUND: We evaluated the analytical performance of a new one-step rapid quantitative sandwich immunoassay for total prostate-specific antigen (tPSA), the FREND™ PSA Plus (FREND PSA) (NanoEnTek Inc., Seoul, Korea). METHODS: The imprecision, linearity, hook effect, detection limit (LoD), and interference were evaluated and trueness verification and matrix validation were performed. For method comparison, 79 patient specimens were analyzed with FREND PSA and two comparative tPSA assays (Architect® total PSA and cobas® total PSA assay). RESULTS: Total CVs of the imprecision for low (0.208 ng/mL), medium (4.051 ng/mL), and high PSA levels (5.469 ng/mL) were 15.9%, 6.4%, and 9.1%, respectively. Linearity was observed from 1.01 to 19.15 ng/mL and the hook phenomenon was absent up to 171.48 ng/mL. The LoD was 0.094 ng/mL. The regression equations between FREND (y) and Architect or cobas were as follows: y=0.0133+1.054x (r=0.973), y=-0.2144+1.066x (r=0.977), respectively. Differences between FREND PSA and the comparative methods at a medical decision level of 4.0 ng/mL were less than the optimum specification bias (9.3%). The percentage biases from the trueness verification and interference test were less than the desirable specifications for bias (18.7%). The plasma tPSA level measured with lithium heparin or K2EDTA was comparable to that in the serum. CONCLUSIONS: The FREND PSA provided reliable analytical performance and test results in comparison to two widely used tPSA assays. It is a simple and rapid test for tPSA and can be applied in point-of-care testing.

Quantitative detection of target cells using unghosted cells (UGCs) of DxH 800 (Beckman Coulter).

BACKGROUND: In the Retic channel of DxH 800 (Beckman Coulter), the red blood cells (RBCs) resistant to hemoglobin clearing are counted as unghosted cells (UGCs). The aim of this study was to evaluate that the UGC is a surrogate marker for both the detection and counting of target cells. METHODS: In total, 1181 samples including 22 from iron deficiency anemia (IDA) patients, 95 from jaundice, 2 from sickle cell anemia, 3 from thalassemia, 1 cord blood, and 269 from normal controls were analyzed. Slides were prepared from all samples except normal controls and target cells were counted for correlation analysis of target cell counts to UGCs. RESULTS: The normal control samples showed 0.01% (0%-0.01%) UGCs, and the reference range was set at ≤0.02%. The IDA samples showed 0.015% (0.01%-0.03%) UGC count and 0.05% (0%-0.2%) target cell count. The jaundice samples showed 0.98% (0.1%-5.36%) UGC count, and 1.4% (0.1%-7.0%) target cell count. The two sickle cell anemia samples showed 0.41% and 3.74% UGC counts and 0.4% and 11.5% target cell counts. A cord blood sample showed 0.01% UGCs and 0% target cells. The three thalassemia samples showed 0.01%, 1.99%, and 7.82% UGC counts and 0%, 1.4%, and 15.5% target cell counts. The samples showing poikilocytosis other than target cells showed normal UGC count (≤0.02%). The positive predictive value of UGCs was 58.2% (124/213) and the negative predictive value was 96.8% (674/696). The UGC counts were well correlated to the manual target cell counts (r=0.944, p=0.000). CONCLUSIONS: This study demonstrates for the first time in the literature that a hematological parameter obtained automatically every time a reticulocyte counting is performed can be used to both screen for the presence of target cells and reliably quantify them.

Evaluation of enzymatic BM Test HbA1c on the JCA-BM6010/C and comparison with Bio-Rad Variant II Turbo, Tosoh HLC 723 G8, and AutoLab immunoturbidimetry assay.

BACKGROUND: A novel enzymatic HbA1c assay was introduced for use in an automated chemistry analyzer. With this unique method, HbA1c and plasma glucose can be measured from the same EDTA tube. We evaluated the analytical performance of this enzymatic HbA1c assay in a JCA-BM6010/C analyzer and compared the HbA1c values with the results from other widely used methodological instruments. METHODS: The imprecision, linearity, carry-over and concordance rate of the enzymatic HbA1c test (BM Test HbA1c) using the JCA-BM6010/C analyzer were evaluated. Three hundred and seventy-seven specimens with HbA1c concentrations from 16 to 133 mmol/mol were used for a comparison study with two high performance liquid chromatography methods: Variant II Turbo and Tosoh HLC 723 G8 and the AutoLab Hemoglobin A1c immunoturbidimetry reagent using a Hitachi 7600-110. Forty specimens were used for the glucose method comparison. RESULTS: The HbA1c coefficients of variation of the within-run imprecision for low and high levels were 0.6% and 0.4%, respectively. The linearity of the BM Test HbA1c using the JCA-BM6010/C analyzer was excellent in the range between 31 mmol/mol and 143 mmol/mol. The carry-over rate was 0.2%. The relationships between the BM test and the other three methods were 0.916×Tosoh G8+3.644, r=0.986; 0.887×Bio-Rad Variant II+1.896, r=0.972; and 0.941×AutoLab+4.532, r=0.977. The concordance rates using a cut-off of 48 mmol/mol were 91.5% with Tosoh G8, 82.8% with Bio-Rad Variant II, and 91.0% with AutoLab. The simultaneously assayed plasma glucose with HbA1c was 1.002×Routine plasma glucose+0.625, r=1.000 CONCLUSIONS: The enzymatic BM Test HbA1c in the JCA-BM6010/C analyzer showed excellent precision and linearity, and a minimal carry-over rate. The simultaneously assayed plasma glucose analysis showed good performance.

Feasibility of a microarray-based point-of-care CYP2C19 genotyping test for predicting clopidogrel on-treatment platelet reactivity.

Clopidogrel is a prodrug which is converted into active metabolite by cytochrome P450 isoenzyme, CYP2C19. Numerous polymorphisms of CYP2C19 are reported, and a strong link exists between loss-of-function (LOF) or gain-of-function polymorphisms, clopidogrel metabolism, and clinical outcome. Hence, a fully automated point-of-care CYP2C19 genotyping assay is more likely to bring personalized antiplatelet therapy into real practice. We assessed the feasibility of the Verigene 2C19/CBS Nucleic Acid Test, a fully automated microarray-based assay, compared to bidirectional sequencing, and performed VerifyNow P2Y12 assay to evaluate the effect of CYP2C19 polymorphisms on on-treatment platelet reactivity in 57 Korean patients treated with clopidogrel after percutaneous coronary intervention. The Verigene 2C19/CBS assay identified ∗2, ∗3, and ∗17 polymorphisms with 100% concordance to bidirectional sequencing in 180 minutes with little hands-on time. Patients were classified into 4 groups: extensive (∗1/∗1; n = 12, 21.1%), intermediate (∗1/∗2, ∗1/∗3; n = 33, 57.9%), poor (∗2/∗2, ∗2/∗3, and ∗3/∗3; n = 11, 19.3%), and ultrarapid metabolizers (∗1/∗17; n = 1, 1.8%). The prevalence of the CYP2C19 ∗2, ∗3, and ∗17 alleles was 36.0%, 12.3%, and 0.9%. Platelet reactivity showed gene dose response according to the number of CYP2C19 LOF allele. In conclusion, the Verigene 2C19/CBS assay gave accurate CYP2C19 genotype results which were in well match with the differing on-treatment platelet reactivity.

A comparison of INNOVANCE® PFA P2Y and VerifyNow P2Y12 assay for the assessment of clopidogrel resistance in patients undergoing percutaneous coronary intervention.

INTRODUCTION: VerifyNow P2Y12 is commonly used to measure responsiveness to clopidogrel. We sought to compare the results obtained from novel INNOVANCE® PFA P2Y and VerifyNow P2Y12 assay to assess the clopidogrel resistance in patients undergoing percutaneous coronary intervention. METHODS: A total of 255 patients undergoing percutaneous coronary intervention, preliminarily treated with 100 mg/day of aspirin followed by coadministration of clopidogrel (loading dose, 600 mg; maintenance dose, 75 mg/day), were enrolled in this study. Platelet aggregation was measured by INNOVANCE® PFA P2Y and VerifyNow P2Y12. RESULTS: INNOVANCE® PFA P2Y and VerifyNow P2Y12 assay showed moderate correlations with INNOVANCE® PFA P2Y vs. VerifyNow%inhibition: r = 0.412, P < 0.0001; INNOVANCE® PFA P2Yvs.VerifyNow P2Y12 reaction units (PRU): r = -0.402, P < 0.0001. The agreement between INNOVANCE® PFA P2Y and VerifyNow%inhibition was 85% and that of INNOVANCE® PFA P2Y and VerifyNow PRU was 79%. The k statistics between INNOVANCE® PFA P2Y and VerifyNow%inhibition and PRU were 0.52 and 0.44, respectively. CONCLUSIONS: The sensitivity of INNOVANCE® PFA P2Y in detecting clopidogrel resistance is comparable to that of VerifyNow P2Y12 assay. As the PFA-100® system is already widely used, the new test cartilage may be a useful tool for the assessment of clopidogrel effects. Additional clinical correlation studies are required to validate the effectiveness of INNOVANCE® PFA P2Y in predicting long-term clinical outcomes.

Glycated albumin may be a possible alternative to hemoglobin A1c in diabetic patients with anemia.

BACKGROUND: We assessed whether glycated albumin (GA) is a useful glycemic indicator in diabetic patients with anemia who did not undergo dialysis. METHODS: Hemoglobin A(1c) (HbA(1c)) and GA were simultaneously measured in 370 diabetic subjects who had not undergone dialysis. The relationship between GA and HbA(1c) was evaluated in patients with and without anemia. RESULTS: GA-to-HbA(1c) ratio was significantly higher (3.3±0.7 vs. 2.8±0.5, p<0.001) and the regression slope between GA and HbA(1c) was steeper in diabetic patients with than in those without anemia (6.2 vs. 4.2, p<0.001). CONCLUSIONS: HbA(1c) was underestimated in diabetic patients with anemia than in those without anemia, with the degree of underestimation increasing as glycemic control became poorer. GA may more accurately assess glycemic control in diabetic patients with anemia than HbA(1c).