A-414 Assessment of the DCA Vantage and Atellica DCA HbA1c Dx Assays Compared to the European Reference Laboratory Method

Background Kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD), are major global health concerns, causing significant morbidity, mortality, and healthcare costs. Serum creatinine is the most widely used biomarker for kidney function and is recommended by clinical guidelines for estimating glomerular filtration rate (eGFR). However, traditional creatinine testing methods require specialized equipment and trained personnel, limiting accessibility, particularly in remote or home settings. Eaglenos has developed a handheld point-of-care testing (POCT) creatinine assay using electrochemical technology for both in-hospital and at-home kidney function monitoring. This system provides a rapid and accessible solution for kidney health assessment, aiding in early detection and management of kidney diseases. This study evaluates its accuracy against reference methods and compares clinical performance, including usability by professionals and non-professionals. Methods Venous whole blood samples were collected by healthcare professionals using lithium heparin-coated tubes. Fingertip capillary blood samples were collected by both healthcare professionals and non-professionals. The study included three comparisons: 1) Analytical performance —Comparison of the Eaglenos system and the reference system (Abbott i-STAT CHEM8+) for venous whole blood samples. 2) Sample consistency—Comparison of venous and fingertip capillary whole blood samples using the Eaglenos system. 3) Usability assessment—Comparison of fingertip capillary blood samples tested by healthcare professionals and non-professionals using the Eaglenos system. Deviation analysis, Bland-Altman analysis, regression analysis, and bias at medical decision levels were used to assess the agreement, correlation, and accuracy. Results A total of 240 cases were analyzed with no dropouts. The main results are: 1) The comparison between the Eaglenos system and the Abbott system using venous whole blood creatinine measurement showed a correlation coefficient (r) of 0.9957 and a coefficient of determination (R2) of 0.9914. 2) The comparison between fingertip capillary whole blood versus venous whole blood creatinine measurements using Eaglenos system yielded an r of 0.9953 and an R2 of 0.9907. 3) The comparison between trained professionals and the non-professionals demonstrated an r of 0.9963 and an R2 of 0.9926. Bland-Altman analysis showed that more than 95% of the data points fell within the limits of agreement (LoA) for both the ratio and percentage difference analyses. All comparisons met the deviation standard, with bias at medical decision levels remaining below 6%, equivalent to ½ the total allowable error (TEa). Conclusion The Eaglenos handheld POCT creatinine assay demonstrated excellent accuracy across venous whole blood, fingertip capillary whole blood, and self-testing scenarios. The system exhibited strong correlation with reference methods, ensuring its reliability for kidney function assessment. With its user-friendly design, this POCT system is well-suited for both in-hospital and at-home monitoring, providing a rapid and accessible kidney health assessment. Its performance at medical decision levels supports its potential for early detection and management of kidney diseases.

Point-of-care testing (POCT) is gaining renewed interest, especially in resource-limiting primary health care, due to rise in prevalence of communicable and non-communicable diseases hence POCT needscontinuous appraisal. Random glucose and glycated haemoglobin (HbA1c) were measured in 104 diabetic patients using standard laboratory multichannel analyzer 917. The utility of venous blood compared to capillary blood in measuring HbA1c was evaluated in a subset of 20 patients using a POCT device, DCA Vantage. Lastly, the POCT was validated against the laboratory multichannel analyser 917, in measurement of HbA1c in a second subset of 46 patients. Random blood glucose levels and HbA1c levels moderately correlated (r2 = 0.56; p < 0.0001). Random glucose tests showed that 41% of the patients had poor glycaemic control while HbA1c showed 74%. Venous and capillary blood in HbA1c showed strong correlation (r2 = 0.89440; p < 0.001. There was also strong correlation (r = 0.9802; p < 0.0001) in HbA1c measured using the DCA Vantage and the standard laboratory analyser, Multichannel Analyser 917. Venous or capillary blood can be used in POCT for HbA1c. POCT is ideal for monitoring glucose control and management of diabetes in resource-limited countries such as South Africa.

A Comprehensive Quality Assurance Platform in Canada for National Point-of-Care Chronic Kidney Disease Screening: The Kidney Check Program

Evaluación de tres sistemas de determinación rápida de hemoglobina A1c para monitorización del control glucémico en pacientes con diabetes mellitus

Point-of-care instruments for the measurement of hemoglobin A1c (HbA1c) may improve the glycemic control of people with diabetes by providing a rapid result if the performance of the instruments used is acceptable. A 0.5% HbA1c difference between successive results is considered a clinically relevant change. With this in mind, the In2it from Bio-Rad and the DCA Vantage from Siemens were evaluated according to Clinical and Laboratory Standards Institute (CLSI) protocols. The CLSI protocols EP-5 and EP-9 were applied to investigate precision, accuracy, and bias. The bias was compared with three certified secondary reference measurement procedures. Differences between capillary and venous blood were investigated by an end-user group consisting of nurse practitioners at a diabetes care center. At HbA1c levels of 5.1 and 11.2%, total coefficients of variation (CV) for the In2it were 4.9 and 3.3%, respectively, and for the DCA Vantage were 1.7 to 1.8% and 3.7 to 5.5% depending on the lot number of the cartridges. Method comparisons showed significant lot number-dependent results for the In2it and the DCA Vantage compared with the three reference methods. No overall difference was observed between capillary and venous blood for both methods. Performance results of the In2it and the DCA Vantage showed variable and lot number-dependent results. To maintain the interlaboratory CV of 5% for HbA1c, the Clinical Laboratory Improvement Amendments rules for waived point-of-care instruments should be revised. An obligation for participating in external quality schemes and taking adequate action should be considered for POC instruments that perform poorly.

Hemoglobin A(1c) (Hb A(1c)) point-of-care (POC) instruments are widely used to provide rapid-turnaround results in diabetic care centers. We investigated the conformance of various Hb A(1c) POC instruments (In2it from Bio-Rad, DCA Vantage from Siemens, Afinion and Nycocard from Axis-Shield, Clover from Infopia, InnovaStar from DiaSys, A1CNow from Bayer, and Quo-Test from Quotient Diagnostics) with generally accepted performance criteria for Hb A(1c). The CLSI protocols EP-10, EP-5, and EP-9 were applied to investigate imprecision, accuracy, and bias. We assessed bias using 3 certified secondary reference measurement procedures and the mean of the 3 reference methods. Assay conformance with the National Glycohemoglobin Standardization Program (NGSP) certification criteria, as calculated from analyses with 2 different reagent lot numbers for each Hb A(1c) method, was also evaluated. Because of disappointing EP-10 results, 2 of the 8 manufacturers decided not to continue the evaluation. The total CVs from EP-5 evaluations for the different instruments with a low and high Hb A(1c) value were: In2it 4.9% and 3.3%, DCA Vantage 1.8% and 3.7%, Clover 4.0% and 3.5%, InnovaStar 3.2% and 3.9%, Nycocard 4.8% and 5.2%, and Afinion 2.4% and 1.8%. Only the Afinion and the DCA Vantage passed the NGSP criteria with 2 different reagent lot numbers. Only the Afinion and the DCA Vantage met the acceptance criteria of having a total CV <3% in the clinically relevant range. The EP-9 results and the calculations of the NGSP certification showed significant differences in analytical performance between different reagent lot numbers for all Hb A(1c) POC instruments.

To assess the usefulness of commutable secondary reference materials with International Federation of Clinical Chemistry (IFCC)-assigned values, for improving the quality of hemoglobin A1c (HbA 1c ) determination. We recalibrated and evaluated 3 point-of-care-test (POCT) devices via 3 different method-specific central laboratory analyzers that were calibrated using commutable specimens with IFCC-assigned values. The staff members who performed POCT were also evaluated before and after training. HbA 1c levels measured with POCT devices showed significantly lesser bias after external mathematical calibration. The interlaboratory CVs for HbA 1c measurements decreased from 12% to 4% after training of POCT-device-operating personnel in the NycoCard group. The CVs in the DCA Vantage and Afinion groups also improved after training. Calibration of laboratory devices by specimens with IFCC-assigned values and by external mathematical calibration could improve the accuracy of POCT HbA 1c measurements. Also, standardized training could improve precision in POCT HbA 1c measurements, especially for semiautomated HbA 1c POCT devices.

Microscopic diagnosis of sodium acetate-acetic acid-formalin-fixed stool samples for helminths and intestinal protozoa: a comparison among European reference laboratories

Accuracy of three hemoglobin A1c point-of-care systems for glucose monitoring in patients with diabetes mellitus

Due to technological advancements, haematology analysers are becoming increasingly more complex. Before introducing new analyzers, laboratories must compare the agreement between the new and the old instruments. This study aimed to quantify the method agreement between Sysmex XT-4000i and Alinity hq analysers in order to establish whether they can be used interchangeably. A total of 415 complete blood counts (CBC) from adult patients of the Emergency Clinical County Hospital of Târgu Mureș, Romania, were analysed within 4 h from the collection on Sysmex XT-4000i (considered the reference method), then on Alinity hq. Statistical analysis consisted of outlier removal, Spearman Correlation, Bland–Altman test, and Passing–Bablok regression. For each CBC parameter, the analytical difference between methods was compared with the Reference Change Value (RCV) at medical decision levels (MDL). Despite using different technologies, the instruments have a good agreement regarding cell differentiation and counting. Cell counting and haemoglobin measurement showed a good agreement at all (Medical Decision Limits) MDLs. The analytical difference between methods surpassed the (Reference Change Value) RCV with 1.2% at the 14% MDL of HCT and with 0.2% at the 100 fL MDL of MCV. This study can not tell whether Sysmex or Alinity is superior, only if the two methods agree. The poorer agreement observed for RBC indices, especially MCHC, suggests an accumulation of differences caused by the different working principles of the two methods. However, it is reasonable to assume that such small differences will not affect clinical decision-making and patient outcome.

Glycemic control is essential to diabetic management, and hemoglobin A1c (Hb A1c) has long been used for this purpose. Though laboratory-based testing is standard, point-of-care (POC) systems provide rapid results in clinic, allowing more timely patient management. A negative bias with POC testing has been observed, and our aim is to further characterize these discrepancies at our institution. A medical record search identified patients who underwent laboratory-based and/or POC Hb A1c testing (DCA Vantage™) at our medical center from July 2015 to April 2016. Patients who underwent both tests within 30 days were grouped by age, sex, and test interval (same day, <1 day, ≤15 days, or ≤30 days). Mean laboratory-based and POC values were compared using the paired t-test. Correlation statistics were determined using the Deming regression. In total, 40503 data points were gathered from the database, comprising 28555 laboratory-based Hb A1c tests and 11948 POC-based Hb A1c tests. A total of 28292 unique patients were identified, of which 493 underwent both tests within 30 days. While DCA and laboratory-based testing was highly correlated, there was a mean negative bias of 0.18% with POC testing. Bias was greater for women [0.17% higher (95% CI, 0.063%-0.284%), P = 0.002] and children aged 0-13 years [0.52% higher (95% CI, 0.141%-0.891%), P = 0.007]. There is a consistent negative bias with POC testing, most pronounced in the female and pediatric populations. Further studies will determine what variables contribute to this discrepancy and how clinical management is modified. POC testing using the DCA Vantage should be interpreted cautiously.

BackgroundSpecies-specific point-of-care tests (POCT) permit a rapid analysis of canine C-reactive protein (CRP), enabling veterinarians to include CRP in clinical decisions. Aim of the study was to evaluate a novel POCT for canine CRP (Point Strip™ Canine CRP Assay) run on a small in-house-analyzer (Point Reader™ V) using lithium heparin plasma and to compare assay performance to an already established canine CRP assay (Gentian Canine CRP Immunoassay) run on two different bench top analyzers serving as reference methods (ABX Pentra 400, AU 5800).Linearity was assessed by stepwise dilution of plasma samples with high CRP concentrations. Limit of quantification (LoQ) was determined by repeated measurements of samples with low CRP concentrations. Coefficient of variation (CV) at low (10–50 mg/l), moderate (50–100 mg/l), and high (100–200 mg/l) CRP concentrations was investigated as well as possible interferences. Method comparison study was performed using 45 samples of healthy and diseased dogs. Quality criteria were fulfilled if the total observed error (TEobs = 2CV% + bias%) was below the minimal total allowable error of 44.4% (TE min). Additionally, a reference range (n = 60 healthy dogs) was established.ResultsLinearity was present at CRP concentrations of 10–132 mg/l (≙ 361 mg/l CRP with reference method) with a LoQ set at 10 mg/l. At moderate to high CRP concentrations, intra- and inter-assay CVs were ≤ 8% and ≤ 11% respectively, while CVs ≤ 22% and ≤ 28% were present at low concentrations. No interferences were observed at concentrations of 4 g/l hemoglobin, 800 mg/l bilirubin and 8 g/l triglycerides. Method comparison study demonstrated an excellent correlation with both reference methods (r = 0.98 for ABX Pentra 400; 0.99 for AU 5800), though revealing a proportional bias of 19.7% (ABX Pentra 400) and 10.7% (AU 5800) respectively. TEobs was 26.7–31.9% and 16.7–21.9% and thus < TEmin. Healthy dogs presented with CRP values ≤11.9 mg/l.ConclusionsThe POCT precisely detects canine CRP at clinically relevant moderate and high CRP concentrations. The assay correlates well with both reference methods. Due to the bias, however, follow-up examinations should be performed with the same assay and analyzer.

The European Commission has designed a network of European Union-National Reference Laboratories (EU-NRLs), coordinated by a Community Reference Laboratory (CRL), for control of hygiene of milk and milk products (Council Directive 92/46/ECC). As a common contaminant of milk and milk products such as cheese, staphylococcal enterotoxins are often involved in human outbreaks and should be monitored regularly. The main tasks of the EU-CRLs were to select and transfer to the EU-NRLs a reference method for detection of enterotoxins, and to set up proficiency testing to evaluate the competency of the European laboratory network. The first interlaboratory exercise was performed on samples of freeze-dried cheese inoculated with 2 levels of staphylococcal enterotoxins (0.1 and 0.25 ng/g) and on an uninoculated control. These levels were chosen considering the EU regulation for staphylococcal enterotoxins in milk and milk products and the limit of detection of the enzyme-linked immunosorbent assay test recommended in the reference method. The trial was conducted according to the recommendations of ISO Guide 43. Results produced by laboratories were compiled and compared through statistical analysis. Except for data from 2 laboratories for the uninoculated control and cheese inoculated at 0.1 ng/g, all laboratories produced satisfactory results, showing the ability of the EU-NRL network to monitor the enterotoxin contaminant.

A case of inter-assay HbA1c discrepancy due to Hemoglobin G-Copenhagen

<h3>Background</h3> Diagnosis of syphilis is problematic and an accurate rapid point of care (POC) test could be useful in busy STD clinics. There are no FDA Cleared POC tests for Syphilis serology in the USA. <h3>Objective</h3> To determine the performance of a new, rapid point of care (POC) test, Syph-Check, which is not yet FDA cleared, for the serological diagnosis of Treponema pallidum in female and male STD patients. <h3>Methods</h3> Men and women &gt;18 yr visiting the Baltimore City Health Department STD clinic were consented to enrol in a trial to determine the accuracy of a new, innovative POC test for syphilis (Veda, manufactured in France) that used a cassette format to test syphilis serology. The Syph-Check One-Step Syphilis test is a point of care, rapid immunoassay screening test for qualitative detection of IgG and IgM antibodies to <i>Treponema pallidum</i> in finger stick blood, plasma, and serum. This product can be used as an initial screening test or as a confirmatory diagnostic test, but is not FDA cleared for use in screening blood or plasma donors. The assay was performed in the STD clinic, required only 20 min to perform, and required no instrumentation. RPR and TPPA tests were performed to determine the sensitivity and specificity of the Syph-Check POC test. <h3>Results</h3> 194 men and 205 women were enrolled. Of the 399 samples tested, 33 were positive and 366 were negative by the Syph-Check. There were 14 positives and 385 negatives by RPR confirmatory testing. Overall sensitivity compared to RPR testing was 85.7% (95% CI 60.3% to 97.5%) and specificity was 94.5% (95% CI 91.9% to 96.5%). There were 32 positives and 367 negatives by TPPA confirmatory testing. Overall sensitivity compared to TPPA was 43.8% (95% CI 27.5% to 61.1%) and specificity was 94.8% (95% CI 92.2% to 96.8%). <h3>Conclusions</h3> The Syph-Check POC test was moderately accurate compared to the RPR test, but not as sensitive compared to TPPA. A more accurate POC test for syphilis could be useful for clinicians to test clinic patients and provide immediate screening results for syphilis to patients during an office or clinic visit.