Architect C8000 Research Articles

Neonatal hemoglobin affects the accuracy of whole blood bilirubin measurement on GEM Premier 4000 blood gas analyzers

ObjectivesWhole blood bilirubin measured on blood gas analyzers is accepted by physicians in neonatal hyperbilirubinemia management since it requires a small sample volume. The accuracy of bilirubin measurement on blood gas analyzers is instrument dependent and remains controversial. Design and MethodsBilirubin in adult and umbilical cord whole blood samples, spiked with an unconjugated bilirubin standard, and non-spiked adult plasma samples was measured on a blood gas analyzer (GEM 4000) and a Core Laboratory Chemistry analyzer (Architect c16000) respectively. We also investigated the linear regression for neonatal and adult hemoglobin measured on the blood gas analyzer and the Core Laboratory hematology analyzer (Alinity h-Series). ResultsPlasma bilirubin measured on the blood gas analyzer and the chemistry analyzer was statistically identical. Adult whole blood bilirubin showed slightly increased proportional bias. When umbilical cord whole blood samples were used, the Deming regression showed GEM bilirubin =1.233(Architect) (95% CI 1.199 ~ 1.266)-44.43 ​μmol/L (95% CI -53.6 ​~ ​−35.2). The regression was significantly different from that in plasma (p ​< ​0.001) or adult whole blood (p ​< ​0.001) samples. 36.1% neonatal samples with bilirubin levels >50 ​μmol/L showed that the bias% was above laboratory standards. In addition, the regression of neonatal hemoglobin measurement between the GEM and the Alinity was significantly different from adult hemoglobin (p ​< ​0.01). ConclusionsNeonatal whole blood bilirubin measurement on blood gas analyzers may be affected by neonatal hemoglobin. The method should be validated using neonatal whole blood samples or samples with a similar matrix before the analyzers are implemented into neonatal hyperbilirubinemia management.

Plasma hemoglobin: A method comparison of six assays for hemoglobin and hemolysis index measurement

Plasma hemoglobin (Hb) is measured for assessment of in vivo and in vitro hemolysis. The objective of the present investigation was to conduct a method comparison of five quantitative and one semi-quantitative Hb and H-index (hemolysis index) assays to evaluate their performance measuring plasma Hb in clinical specimens. One hundred and fourteen clinical specimens previously tested for plasma Hb using a laboratory-developed spectrophotometric assay were also tested for Hb using a HemoCue Plasma/Low Hb assay (azide methemoglobin), a laboratory-modified Pointe Scientific Hb assay (cyanmethemoglobin), tested for H-index measurements using a Roche cobas c501, an Abbott Architect c8000, and a semi-quantitative (binned) H-index measurement on a Beckman AU5800. The reference result was defined as the median Hb score (median of all Hb or H-index results). The laboratory-developed spectrophotometric Hb assay and Roche H-index methods mostly closely matched the median Hb score across all data, as well as for lower range median Hb score results ≤2.0g/L. Two-way frequency table analysis using an Hb (or H-index) cutoff of 0.5g/L (or 0.5 H-index units) was then performed to compare methods to the median Hb score cutoff. The Beckman method had the highest accuracy at this cutoff, the Roche and Abbott methods had the highest positive predictive value (PPV), and the Beckman, HemoCue, and Pointe methods had the highest negative predictive value (NPV). Plasma Hb and H-index results vary by method. Laboratories should evaluate the performance characteristics of their respective assays when considering adoption of spectrophotometric or chemical methods for plasma Hb assessment.

The effect of haemolysis on the direct and indirect ion selective electrode measurement of sodium.

We compared the effect of haemolysis in sodium measurement using indirect and direct ion-selective electrodes to test the hypothesis that haemolytic effect on sodium would be greater with indirect ion-selective electrode due to electrolyte exclusion effect from released intracellular proteins. Plasma lithium heparin samples (n = 36) from four volunteers were prepared to give a range of haemolytic indices (H-indices). Samples were analysed for sodium by indirect ion-selective electrode, H-index and total protein on an Abbott Architect c16000 and sodium by direct ion-selective electrode on a Siemens RAPIDPoint 500. Percentage changes in sodium in paired direct and indirect ion-selective electrode values were compared. Abbott H-index, which represents haemoglobin concentration in g/L, correlated with percentage negative change in sodium by direct ion-selective electrode (ρ 0.995, P < 0.001) and indirect ion-selective electrode (ρ 0.991, P < 0.001). Percentage negative change was less when sodium was measured by direct ion-selective electrode compared to indirect ion-selective electrode (Wilcoxon signed-rank Z = 3.46, P = 0.01). The difference in percentage change in sodium between direct ion-selective electrode and indirect ion-selective electrode correlated with total protein (ρ 0.751, P < 0.001). The negative bias in sodium results exceeded the reference change value of 2.2% at an H-index of 8.31 for indirect ion-selective electrode and 9.26 for direct ion-selective electrode. Haemolysis causes negative influence with sodium measured by both indirect and direct ion-selective electrode due to a dilutional hyponatremia. The additional interference in indirect ion-selective electrode is due to the electrolyte exclusion effect but this is unlikely to be clinically significant as it is small in magnitude.

ACUTE GASTROENTERITIS IN CHILDREN

The aim of the study was to investigate the most frequent etiology of AGE in children admitted аt our hospital, and the correlation with severity of clinical manifestation. The study was designed as a prospective study, and we examined 219 pediatric patients with AGE admitted at the University Children’s Hospital–Skopje. The diagnosis of AGE was based by the definition for AGE as a decrease in the consistency of stools (loose or liquid), and/or an increase in the frequency of evacuations (typically &gt;3 in 24 hours), with or without fever or vomiting. The stool specimens were examined using the new multiplex polymerase chain reaction–based rapid diagnostic test–Film Array Gastrointestinal panel test. White blood cell levels (10^3/ul) and hemoglobin levels (g/dL), were determined by using the flow citometry method on Sysmex xs 800i/1000i. Iron levels (µmol/L) were determined by using the biochemistry analyzer Architect c4000 Abbott. Statistical analysis confirmed significantly different values of stool isolation: viruses and bacteria in the groups&nbsp; p&lt;0.001. The stool parasites were insignificant p&gt;0.05. Statistical analysis confirmed significantly different values ​​of WBC levels in the groups&nbsp; p&lt;0.001. Statistical analysis confirmed significantly different values of iron levels in the groups&nbsp; p&lt;0.001. Statistical analysis confirmed significantly different values of h​emoglobin levels in the groups p&lt;0.001. Film Array Gastrointestinal panel test is a useful tool in the rapid diagnosis of gastrointestinal pathogens in pediatric patients with acute gastroenteritis.&nbsp; Keywords: Acute gastroenteritis (AGE), pediatric patients immunocomtentence, pediatric patients, immunocompromised, Film Array Gastrointestinal panel test. https://doi.org/10.55302/JMS2143040b

ENZYME DIAGNOSTICS IN SPORTS PRACTICE (LITERATURE REVIEW AND PERSONAL EXPERIENCE)

Aim. The paper aims to analyze and summarize the data about enzyme diagnostics in athletes of different sports. Materials and methods. Creatine kinase (CK) activity was measured in 20 highly skilled male biathletes aged from 18 to 23 years. Fasted blood samples were taken in the morning before exercise and the next day after a 90-minute ski run by a uniform method. Biochemical analysis was performed by using the Architect c4000 and i1000SR (Abbott, USA) automated analyzers with reagents and control materials from the equipment manufacturer. Results. An increase in CK activity in biathletes is observed at the end of the preparatory period, and normalization occurs by the middle of the competitive period. When studying CK activity in 10 male handball players aged from 18 to 21 years the day after training, it was found that the increase in enzyme activity depended on the playing position. Goalkeepers exceeded the norm many times compared to field players. The highest serum CK activity after exercise was observed after prolonged exercise such as extra-long marathon and uphill running, which involved eccentric muscle contractions. In triathletes after competitions (full distance), CK activity increased to 1200 U/L, after 48 hours of recovery it dropped to 400 U/L. Conclusion. Thus, enzyme diagnostics today is a relevant and objective method for assessing the state of health and the muscular system, including organs such as the heart, liver, and brain. Therefore, control over the level of basic enzymes should be carried out regularly in the preparatory period both as part of an in-depth medical examination and if an athlete is suspected of being overtrained or injured.

Performance evaluation of all analytes on the epoc® Blood Analysis System for use in hospital surgical and intensive care units

ObjectiveTo evaluate the performance of the epoc hand-held analyzer against the RAPIDPoint 500 blood gas analyzer and laboratory analyzers where applicable. MethodsVenous or arterial whole blood samples collected in balanced heparinized syringes were obtained from 69 patients (35 females, 34 males) predominantly (77%) from the surgical unit and intensive care unit (ICU). Method comparison was performed for all analytes on the epoc System against the RAPIDPoint 500 Blood gas analyzer or laboratory analyzers where applicable. Results: Mean bias was <5% for blood gases, electrolytes, lactate and glucose. Hematocrit showed a bias of -6.76% (95% CI ​= ​-8.91, - 4.61) compared to the HemataSTAT-II method, whereas calculated total hemoglobin showed a bias of 1.51% (95% CI ​= ​-1.04, 4.06) against the Sysmex XN-10 hematology analyzer. Creatinine showed the largest bias relative to laboratory analyzers, Abbott Architect c8000 Jaffe method (13.54%, 95% CI ​= ​5.43, 21.65) and Roche Cobas c702 enzymatic method (30.01%, 95% CI ​= ​12.64, 47.38). Conclusions: The epoc system is fit for use in the surgical and ICU setting for the measurement of all analytes except for creatinine.

Lipemic Interference in Basic Metabolic Panels: Increasing the Lipemia Index Threshold in Order to Decrease the Frequency of Ultracentrifugation

Abstract Introduction Lipemia in clinical chemistry samples is a problematic form of interference. Clearing these samples for routine testing can be time consuming and increases the turn-around time for these specimens. In our laboratory, samples with a lipemia index &amp;gt;50 (L-index) are manually inspected and visibly lipemic specimens are cleared by ultracentrifugation. Objective The objective of this study was to determine at what L-index ultracentrifugation of lipemic BMP specimens is necessary prior to sample testing to ensure accurate results. Methods Specimens consisted of routinely ordered basic metabolic panels (BMP) that met current criteria for ultracentrifugation, which included an L-index &amp;gt;50 as measured on the Abbott Architect c8000 and visual lipemia. Specimens meeting these criteria were ultracentrifuged and retested. The difference of the pre-ultracentrifuged and post-ultracentrifuged result was evaluated and put into a percent to find the ‘percent difference’ and evaluated against the total allowable error (TEa) for each analyte. If the difference observed following ultracentrifugation was less than or equal to 50% of the TEa, clearance of lipemia by ultracentrifugation was considered unnecessary. Values from all BMP component tests were analyzed in order to find an L-index threshold at which samples need to be ultracentrifuged which could be applied to the entire panel. The report of lipemic indices for BMPs for the month of January 2020 were extracted from the laboratory information system to evaluate the potential impact of altering the L-index threshold for ultracentrifugation. Results Based on the acceptance criteria of ≤50% of TEa, L-index thresholds for Na, K, Cl, calcium, glucose, creatinine, CO2 and BUN were &amp;lt;203, &amp;lt;410, &amp;lt;287, &amp;lt;387, &amp;lt;410, &amp;lt;285, &amp;lt; 153 and &amp;lt;285, respectively. All the calculated differences or percent differences for each analyte did not exceed 50% of the TEa for a given analyte when the L-index was 150 or less. Adjusting the L-index to 150 and applying it to the 195 lipemic BMP samples in January 2020, would have potentially decreased the number of samples requiring ultracentrifugation to 24 lipemic BMPs (88% reduction). Conclusion These data suggest that an L-index greater than 150 can be used for all analytes within a BMP as the threshold for requiring ultracentrifugation. The BMP is one of the most frequently ordered tests in our laboratory and consistently accounts for a substantial portion of the lipemic samples that require ultracentrifugation. Increasing the L-index at which samples will be ultracentrifuged from 50 to 150 would potentially result in an 88% reduction in one month of BMP samples requiring ultracentrifugation.

Inaccuracy of Sodium Measurement in Patients with Severe Hypernatremia.

We observed discordant sodium results from a patient with severe hypernatremia such that whole-blood analysis produced results up to 9.6 mmol/L higher than plasma sodium obtained on the same collection. We investigated this bias by comparing other patients' sodium results and performing comparisons of 3 blood gas and 2 chemistry analyzers. First, the laboratory information system was queried for whole-blood sodium results >160 mmol/L, which were used for comparison against plasma results from the same collection. Second, whole blood was collected from a healthy donor, a portion of which was spiked with sodium chloride to generate 8 samples with target concentrations of 140 to 185 mmol/L. Whole-blood sodium was measured in duplicate on the ABL90, RAPIDPoint 500, and GEM 4000. Plasma sodium was then measured in duplicate on the Architect c8000 and Cobas c702. Finally, plasma was injected on the blood gas analyzers to measure sodium in singleton. Overall, 53 paired results from patients showed a significant positive bias on the ABL90 relative to Vitros when sodium was >160 mmol/L. The magnitude of difference was insignificant within the reference range but increased proportionately with concentration. The magnitude and pattern of positive bias in ABL90 sodium results were consistent with the observation in patient results. In severe hypernatremia, sodium results produced by blood gas and plasma analyzers can differ significantly.

High dose ascorbic acid treatment in COVID-19 patients raised some problems in clinical chemistry testing

Abstract Objective COVID-19 pandemia still continues to threaten the whole world. High dose ascorbic acid (AA) infusion is a choice of treatment and its efficiency is still being investigated. AA interferes with many clinical chemistry tests. However, data about the interference of high concentrations of AA is not sufficient. In this study, we aimed to investigate the interference of AA at high concentrations on commonly used chemistry assays. Materials and Methods Serum samples at AA concentrations of 200, 150, 100, 75, 50, 25, 10, 5, 2 and 0 mg/dL were prepared by using the stock solution of 15000 mg/dL AA. Each sample was analyzed by using the most common 30 chemistry tests (Abbott Architect C8000, Illinois, USA) and a POCT glucometer (STANDARD GlucoNavii, Gyeonggi-do, Republic of Korea). Results Creatinine, sodium and glucose (POCT) tests were found to be positively interfered by increasing AA concentrations; while direct bilirubin, lipase, UIBC, triglyceride, total cholesterol, HDL/LDL cholesterol tests were negatively interfered. Absolute interference (%) increased as the AA concentration increased. Conclusion This is the largest and first study to investigate the interference of high dose AA, which is used in severe COVID-19 patients nowadays. Manufacturers and clinicians should be aware of the possibility of aberrant results due to high dose AA infusion. Clinicians should not forget to consult a laboratory specialist, since he is the only person to monitor the reactions in all assays, and know the technical subjects like interferences, assay method specifications. This issue is very important for correct decision-making and interpretation of the data-mining studies accurately and efficiently.

Analytical Evaluation of ABL90 Flex Plus Blood Gas Analyzer for Urea and Creatinine

Background Acute kidney injury is a common complication among hospitalized patients. The availability of creatinine and urea measurements as point-of-care testing provides an alternative strategy to monitor renal function and develop prevention strategies, especially in the emergency services, where reducing waiting times and rapid clinical decisions may be required. Objective The aim of this study was to evaluate if creatinine and urea measurements are interchangeable between ABL90 Flex Plus and three common central laboratory methods. Methods With a multicenter design, creatinine and urea were first analyzed by ABL90 Flex Plus and then by laboratory method: Dimension Vista 1500, Cobas c702, and Architect c16000 according to Clinical and Laboratory Standards Institute EP09-A3 protocol. All measurements were performed in duplicate. Results were evaluated using Passing-Bablok regression and Bland-Altman comparison. Interchangeability of patient results was verified at different clinical decision levels. Results Passing-Bablok regression between the 3 central laboratory methods and ABL90 Flex Plus showed correlation coefficients over 0.998 for creatinine and 0.994 for urea, and despite the presence of proportional and/or constant bias observed in the study, estimated difference was lower than the allowable difference (±15.6% for urea and ±8.9% for creatinine) at clinical decision levels in all cases. Conclusion Creatinine and urea measurements are interchangeable using ABL90 Flex Plus blood gas analyzer compared with 3 central laboratory methods, ensuring no impact on patient care using indistinctly any analyzer.

Influence of reagent lots and multiple measuring systems on estimating the coefficient of variation from quality control data; implications for uncertainty estimation and interpretation of QC results.

Background Clinical laboratories use internal quality control (QC) data to calculate standard deviation (SD) and coefficient of variation (CV) to estimate uncertainty of results and to interpret QC results. We examined the influence of different instruments, and QC and reagent lots on the CV calculated from QC data. Methods Results for BioRad Multiqual frozen liquid QC samples over a 2-year interval were partitioned by QC and reagent lots. The mean and CV were calculated for each partition for each of three Abbott Architect c8000 instruments for measuring serum alanine amino transferase (ALT), creatinine (enzymatic), glucose and sodium. Results CVs differed among partitions and instruments for two QC levels by 5.8- and 3.3-fold for ALT, by 4.7- and 2.1-fold for creatinine, by 2.0- and 2.6-fold for glucose, and by 2.1- and 2.0-fold for sodium. Pooled CVs for two QC levels varied among instruments by 1.78- and 1.11-fold for ALT, by 1.63- and 1.11-fold for creatinine, by 1.08- and 1.06-fold for glucose, and by 1.24- and 1.31-fold for sodium. Conclusions The CVs from QC data varied substantially among QC and reagent lots and for different identical specification instruments. The CV used to estimate uncertainty for a measurement result or as the basis for interpreting individual QC results must be derived over a sufficient time interval to obtain a pooled CV that represents "typical" performance of a measuring system. An estimate of uncertainty provided to users of laboratory results will itself have uncertainty that can influence medical decisions.

Correlations between Direct and Calculated Low-Density Lipoprotein Cholesterol Measurements in Children and Adolescents.

BackgroundLow‐density lipoprotein cholesterol (LDL‐C), as a modifiable risk factor for atherosclerotic cardiovascular disease, should be assessed and monitored. This study compared directly measured and Friedewald‐estimated LDL‐C values in children and adolescents.MethodsBlood samples were collected from 464 children and adolescents. Calculated LDL‐C (CLDL‐C) levels were estimated using the Friedewald formula for any triglyceride value below 4.6 mmol/L. Direct LDL‐C (DLDL‐C) levels were measured on an ARCHITECT c8000 Abbott Clinical Chemistry Analyzer. The differences in LDL‐C were then calculated.ResultsThe correlation coefficients (R) between DLDL‐C and CLDL‐C were 0.978 (P = .148) and R = 0.970 (P = .052) for children and adolescents, respectively. Children with LDL‐C values above 4.92 mmol/L had a correlation value of 0.971 (P = .419). The correlation and agreement between DLDL‐C and CLDL‐C in adolescents were moderate for LDL‐C below 2.85 mmol/L (R = 0.806; 84.1%) and improved above 2.85 mmol/L (R = 0.978; 91.5%). In children, good correlations between DLDL‐C and CLDL‐C were observed for normal (<0.85 mmol/L), borderline (0.85‐1.12 mmol/L), and abnormal (≥1.13 mmol/L) triglyceride levels (R = 0.9782, 0.990, and 0.951, respectively). The rates of agreement were better for normal (80.5%) and borderline (82.9%) but not abnormal (68.2%) triglyceride levels.ConclusionWe observed good agreement between DLDL‐C and CLDL‐C in both children and adolescents. The Friedewald formula provided an adequate estimate of LDL‐C for most fasting specimens. LDL‐C difference percentage can also be used as a quality indicator to check laboratory analyzer performance in healthy subjects.

An investigation of the relationship between base deficit and crp in asphytic infants

Aim: To investigate the relationship between base deficit (BD) and C-reactive protein (CRP) findings evaluated during diagnosis of infants followed up for a diagnosis of perinatal asphyxia (PA).Material and Methods: This prospective observational study included 66 cases as 33 cases treated and followed up for a diagnosis of PA in the Neonatal Intensive Care Unit of Harran University Medical Faculty Hospital, and a control group of 33 healthy infants. Using a syringe washed with heparin, a fetal blood sample of 2ml was taken from the umbilical artery of the neonates thought to have PA, and blood gases were examined in an anaerobic environment. CRP values were obtained from spectrophotometric biochemical analysis of the 2ml blood sample using an Architect C16000 device (Abbott Diagnostics, Abbott Park, IL, USA). Results: Evaluation was made of 33 infants with a diagnosis of PA hospitalised in NICU and a control group of 33 healthy infants. All the cases were statistically similar in respect of gestational week at birth (GW), birthweight (BW), and gender. In the blood gas examinations of the cord blood, pH value was determined as mean 6.9 (range, 6.50-7.06), mean BD as 17mmol/L (range, 12-28 mmol/L), and CRP values as 0.2-57 mg/dl. The CRP values of the PA cases on days 2 and 3 were determined to be significantly higher than those of the control group (p0.001). As the BD value at the time of diagnosis increased, so there was determined to be a significant increase in CRP value, and this was confirmed by the Spearman correlation test (r1:0.423, p1:0.014) (r2:0.342, p2:0.05) (r3:0.451, p3:0.009). No statistically significant relationship was determined between the pH value in blood gas and the CRP level (p:0.18). Conclusion: The results of this study demonstrated that the CRP level was statistically significantly higher in cases that developed asphyxia than in the control group. A positive correlation was determined between BD at diagnosis and CRP level. A high CRP level during treatment and follow-up can be considered for use as a supportive finding showing the severity of hypoxia.

A Pilot Study on the Evaluation of Clinical Chemistry Laboratory Test Performance using Six Sigma Metrics

Introduction Six sigma has been used over the years, initially in manufacturing industries to improve quality by reducing the number of wastes and defects. In the laboratory, it can also provide measurement of quality using the sigma scale. Objectives The main objective of the study is to evaluate the performance of tests in two chemistry analyzers using the six sigma scale. Methodology A total of twenty (28) tests were evaluated on two Abbott Architect c8000 chemistry analyzers from September 2014 to July 2019 using results of quality control mean, coefficient of variation, bias and total allowable error to compute for the six sigma value. Both level one and level two third party quality controls were included in the evaluation. Results OResults of the study showed the tests that were >6 sigma for both levels 1 and 2 throughout the 5 years. Di-Bil, CK, HLD, TG and UA were consistently >6 sigma for one machine while CK, Di-Bil, HDL, Mg, TG and UA were consistently >6 sigma for the other. Level 1 and Level 2 sigma scores were noted to be incongruent in some analytes as follows: ALB, ALT, K, TP for one instrument and ALB, ALP and AST for the other instrument. Electrolytes Ca, Cl, and Na were generally low ( Conclusion Using six sigma metrics allowed the laboratory to evaluate the performance of the chemistry tests objectively. Tests that are >6.0 sigma signifies world class performance and entail application of fewer Westgard rules with fewer number of runs while those that are

Anion gap reference intervals show instrument dependence and weak correlation with albumin levels

BackgroundAnion gap (AG) aids the differential diagnosis of acid-base disorders. Its value has decreased, because of new analytical methods. Our goal was to compare AG reference intervals for different instruments and Southeast Asian populations. MethodsWe studied AG at three hospitals. One used the cobas 8000; two others, the Architect c16000. We included consecutive adults ≥18 years whose samples were sent for electrolytes and creatinine. We assessed AG for all patients and patients with normal electrolytes. ResultsAG means differed significantly (P < 0.001) between the three hospitals for all patients and the normal electrolyte subgroup. AG reference intervals from all patients were 9–19, 5–15, and 5–15 mmol/L, and for the normal electrolyte subgroup, 10–17, 6–14, and 5–12 mmol/L, respectively. Compared to the normal albumin group, hypoalbuminemia patients showed lower AG in two hospitals (P < 0.001, P = 0.03), whereas patients with hyperalbuminemia demonstrated higher AG in all three hospitals (P < 0.001). ConclusionsDifferent instruments produce different AGs. There is a weak correlation between albumin levels and AG. Laboratorians should verify reference intervals used when detecting laboratory errors and assisting clinicians in the differential diagnosis of acid base disorders and other medical conditions.

Hemolysis has no influence on routine coagulation tests in subjects without anticoagulant therapy - a referral Romanian emergency hospital laboratory experience

Abstract The aim of this study was to determine the rate of hemolyzed specimens sent to our laboratory for coagulation testing, assess the interference of hemolysis on coagulation for patients without anticoagulant therapy and to determine the reference intervals for PT, INR and aPTT for our laboratory in order to test our own limitations. Methods: To determine the hemolysis rate, 1,689 specimens were evaluated on a visual scale and with the hemolysis icterus lipemia (HYL) test on Architect c4000 instrument. 125 blood samples collected from subjects without anticoagulant therapy were hemolyzed in vitro and the PT, INR and aPTT results were compared before and after hemolysis.To determine reference intervals (RI) for PT, INR and aPTT in our population, 125 apparently healthy human subjects (according to CLSI C28-A2) were enrolled and tests were performed on Sysmex CS 2000i, using Siemens reagents. Results: Out of 1,689 samples, 9.46% were assessed as hemolyzed by the visual scale, while HYL test showed a 6.63% hemolysis rate. We found a shortening of 0.1s for PT, a diminution with 0.01 units for INR and a prolongation with 0.9s for aPTT from in vitro hemolyzed compared to non-lyzed samples. As to the reference intervals, we obtained in our laboratory versus reagents producer: for PT 9.8-13.9 s vs 9.8-12.1 s, and for aPTT 19.1-31.5s vs 23-31.9 s respectively; 28.38% more PT results and 13.44% more aPTT results were within range when we used local laboratory RI, compared to the manufacturer’s RI. Conclusions: The rate of hemolyzed coagulation samples in our laboratory is higher than the rate found in the literature. Nevertheless, for patients without anticoagulant therapy hemolyzed samples should be processed. Using our own reference interval leads to a significant reduced number of abnormal results.

Good Agreement Between Hba1c Analyzed Using Capillary Electrophoresis, HPLC, Immunological and Enzymatic Methods

Purpose: Hemoglobin A1c (HbA1c) is an essential marker for assessment of glycemic control in diabetes patients. The aim of this study was to evaluate the agreement between different HbA1c methods. Methodology: We used blood samples to compare HbA1c results analyzed with Capillarys 3 Tera, Roche Tina-Quant HbA1c Gen 3, BioRad Variant II Turbo (3 sites), Mono S® and Abbott Architect enzymatic method. The comparisons were made as paired instrument comparisons with Capillarys 3 Tera. Results: The linear correlations between the HbA1c methods were as follows: Cobas 6000 = 0.982 x Capillarys 3 Tera + 0.975, R² = 0.994; Architect c8000 = 0.982 x Capillarys 3 Tera + 1.064, R² = 0.994; Mono S® = 0.916 x Capillarys 3 Tera + 3.397, R² = 0.965; BioRad Variant II Turbo = 0.923 x Capillarys 3 Tera + 4.062, R² = 0.990; Tosoh G8 = 0.963 x Capillarys 3 Tera + 3.895, R² = 0.996. Conclusions: The different instrument platforms showed the best agreement in the 50-70 mmol/mol interval. Above and below this range the methods separated into 2 groups, one consisting of Capillarys 3 Tera, Roche Tina-Quant and Abbott enzymatic method and the other group consisting of BioRad Variant II Turbo, Tosoh G8 and Mono S®.

The Utility of Beta 2 Microglobulin (B2M) as an Initial Diagnostic Tool for Oral Squamous Cell Carcinoma (OSCC): Evidence from a Malaysian Scenario

Background: The delay in diagnosis of oral squamous cell carcinoma (OSCC) is a factor in rendering the poor prognosis, and recent research has explored the use of serum tumour markers such Beta 2 Microglobulin (B2M), to aid early diagnosis. However, despite a high incidence of OSCC in Southeast Asia, no studies on the clinical use of B2M in the region were found.&#x0D; Objectives: To determine if serum B2M level can serve as an initial diagnostic tool to indicate if a biopsy is warranted, and if so, to propose a local B2M serum reference value to identify OSSC patients.&#x0D; Methodology: Twenty-one patients were seen at Hospital Universiti Sains Malaysia (HUSM) for a one-year period, between June 2016 and June 2017, and equal number of healthy controls participated in the study. Apart from patient history, venous blood of approximately 5ml volume was collected from each subject at the pre-treatment stage and analysed by an Abbot ARCHITECT c8000 analyser using the immunoturbidimetry method. The results were analysed using ROC analysis and the Mann Whitney test.&#x0D; Results: Serum B2M levels showed a statistically significant increase (p&lt;0.001) in patients compared to controls. The test was shown to have 90.5% sensitivity and 90.5% specificity. It was found to be a sensitive and specific serum tumour marker at a cut off value of 1.57mg/l to differentiate cases from controls.&#x0D; Conclusion: B2M is a sensitive and specific tumour marker to differentiate OSCC cases from controls. It is cost effective and minimally invasive, making it a potentially useful adjunct diagnostic tool in a high-risk patient pool.&#x0D; Bangladesh Journal of Medical Science Vol.18(4) 2019 p.729-735

Evaluation of the i-STAT Alinity Point-of-Care Analyzer

Objectives The objective of this study was to evaluate the analytical performance of CG4+ and CHEM8+ cartridges on the i-STAT Alinity analyzer prior to use in patient testing. We also evaluated the ease of use, design, and safety features to determine its suitability for use by the clinicians in our hospital. Methods The Abbott i-STAT System Performance Verification Protocol was observed for the imprecision study and was performed over the course of 2 days using 2 levels of control material (Abbott i-STAT TriControl Level 1 and Level 3). The CLSI-EP6-A guideline was used to verify the assay reportable range performance using 5 levels of linearity material (Abbott i-Stat TriControl Calibration Verification Set). The method comparison study was performed using up to 60 leftover anonymized heparinized whole-blood samples and serum samples against existing laboratory instruments (Siemens Rapidpoint 500, Abbott Architect C16000, and Sysmex XN9000). Results Precision was good (coefficient of variation <2%) for electrolytes, glucose, lactate, and pH, and satisfactory (coefficient of variation <5.2%) for blood gases, urea, creatinine, and hematocrit. Linearity concentrations spanning the analytical measuring ranges were demonstrated for all analytes. Method comparison studies revealed that agreement between the i-STAT Alinity analyzer and the central laboratory analyzers was good and clinically acceptable. Conclusions The i-STAT Alinity analyzer has good analytical performance, and we established the analyzer meets our safety and regulatory requirements and therefore suitable for use in our hospital as a point-of-care testing device.

Evaluation of the analytical applicability of the 0H/1H high-sensitivity cardiac troponin algorithm in a multimodular setting

Anion gap (AG) aids the differential diagnosis of acid-base disorders. Its value has decreased, because of new analytical methods. Our goal was to compare AG reference intervals for different instruments and Southeast Asian populations.We studied AG at three hospitals. One used the cobas 8000; two others, the Architect c16000. We included consecutive adults ≥18 years whose samples were sent for electrolytes and creatinine. We assessed AG for all patients and patients with normal electrolytes.AG means differed significantly (P < 0.001) between the three hospitals for all patients and the normal electrolyte subgroup. AG reference intervals from all patients were 9–19, 5–15, and 5–15 mmol/L, and for the normal electrolyte subgroup, 10–17, 6–14, and 5–12 mmol/L, respectively. Compared to the normal albumin group, hypoalbuminemia patients showed lower AG in two hospitals (P < 0.001, P = 0.03), whereas patients with hyperalbuminemia demonstrated higher AG in all three hospitals (P < 0.001).Different instruments produce different AGs. There is a weak correlation between albumin levels and AG. Laboratorians should verify reference intervals used when detecting laboratory errors and assisting clinicians in the differential diagnosis of acid base disorders and other medical conditions.