Sysmex CS-5100 Research Articles

B-013 Improving the Workflow of Blood and Coagulation Tests in clinical laboratory through the Utilization of Laboratory Automation Track Systems

Abstract Background The Laboratory Automation Track System (TLA) is an automated system designed for executing highly repetitive tasks within a laboratory, commonly applied in biochemical and immunological testing systems. It aims to reduce human errors in specimen handling, enhance the overall process quality, and provide better Turnaround Time (TAT) from specimen collection to result reporting. For the first time in our laboratory, we have integrated the blood and coagulation systems with TLA. Consequently, we seek to evaluate the differences in the testing workflow and reporting efficiency of the blood and coagulation systems after being connected to TLA. Methods Abbott GLP systems Track was the TLA system for connecting with blood and coagulation systems. Two Sysmex XN-9100 fully automatic hematology systems and two Sysmex CS-5100 fully automatic coagulation analyzers were developed for blood and coagulation system, respectively. TUNYEN Laboratory Information System was established for Laboratory information system (LIS). Results Through the analysis of quality indicators and integration with intelligent information systems, improvements have been made, including the reduction of blood collection tube usage, efficient manpower utilization management, tracking of specimen progress and achievement of timely reporting rates.(1)Approximately 2,915 blood collection test tubes are saved every month, with a converted cost of 0.15 USD per tube, and a total saving of 437 USD. And reduce the carbon emissions of 32 kgCO2e, comply with the spirit of ESG sustainable development.(2)The TLA no longer requires staff to collect and deliver specimens as in the past,reducing staff and enhancing work efficiency.One of manpower was saved and new inspection items were developed.(3)Tracking of specimen progress:The laboratory has set up a specimen tracking system to monitor the specimen delivery location and provide timely response to the clinical status.The one-hour TAT for blood and coagulation increased from 82.0% and 76.9% before improvement to 91.8% and 93.3% after improvement respectively. Conclusions The implementation of Laboratory Automation Track Systems (TLA) leads to a reduction in medical errors and specimen sample volume, while also enhancing accuracy and precision, thereby improving the safety of laboratory staff. Although the introduction of TLA may require an initial investment, it brings the benefits of automation, offering ease and efficiency to laboratory processes.

Heparin-Calibrated Anti-Factor Xa Assay for the Measurement of Direct Anticoagulants such as Apixaban, Rivaroxaban, and Edoxaban.

The first purpose of this study was to determine whether a measurement of the level of direct oral anticoagulants (DOACs) was possible with heparin-calibrated chromogenic anti-factor Xa activity (AXA). The second purpose of this study was to evaluate whether the antidote treatment decision level (30 or 50 ng/mL of DOAC) can be determined by unfractionated heparin (UHF)/low molecular weight heparin (LMWH)-calibrated AXA. AXA was measured by using two reagents and dedicated analyzers (Sysmex CS-5100 analyzer and STA R Max3). Four types of calibrators were used: 1) Stago DOAC (rivaroxaban, edoxaban, and apixaban)-specific calibrator, 2) Stago LMWH calibrator, 3) Sysmex UHF calibrator, and 4) Sysmex LMWH calibrator. Regression analysis was used between assays. Receiver operating characteristic (ROC) curves were performed, and the concordance rate was calculated. The correlation coefficients were in the range of 0.75 - 0.91 for rivaroxaban and 0.81 - 0.94 for apixaban. The correlation coefficient between edoxaban-calibrated AXA and Sysmex LMWH/Sysmex UHF calibrator-calibrated AXA was low (r = 0.47). Overall correlation between DOAC-calibrated AXA and Stago LMWH-calibrated AXA was linear, at only low concentration in all three DOACs. The concordance rate (89.3 - 100%) is good for de-termining the antidote management level by UFH/LMWH-calibrated AXA, compared with those of DOAC-calibrated AXA in rivaroxaban and apixaban. The concordance rate ranged from 63% to 67% between Sysmex UFH/ LMWH-calibrated AXA and edoxaban-calibrated AXA. The findings of our study suggest limitations in calculating accurate concentrations, when using UFH/LMWH-calibrated AXA to measure DOAC. This study demonstrates that UFH/LMWH-calibrated AXA may be useful in determining the presence of DOACs at the cutoff level for the antidote treatment in rivarovaban and apixaban. However, in edoxaban, UFH/LMWH-calibrated AXA could not accurately measure the presence of DOACs at the cutoff for antidote treatment.

The clinical significance of TAT, PIC, TM, and t-PAIC in vascular events of BCR/ABL-negative myeloproliferative neoplasms

Predicting the likelihood vascular events in patients with BCR/ABL1-negative myeloproliferative neoplasms (MPN) is essential for the treatment of the disease. However, effective assessment methods are lacking. Thrombin-antithrombin complex (TAT), plasmin-α2- plasmininhibitor complex (PIC), thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex (t-PAIC) are the new direct indicators for coagulation and fibrinolysis. The aim of this study was to investigate the changes of these four new indicators in thrombotic and hemorrhagic events in BCR/ABL1-negative MPN. The study cohort of 74 patients with BCR/ABL negative myeloproliferative disorders included essential thrombocythemia, polycythemia vera, and primary myelofibrosis (PMF). A panel of 4 biomarkers, including TAT, PIC, TM, and t-PAIC were determined using Sysmex HISCL5000 automated analyzers, whereas fibrin/fibrinogen degradation products (FDP), D-dimer and Antithrombin III (ATIII) were analyzed using Sysmex CS5100 coagulation analyzer. A total of 24 (32.4%) patients experienced thrombotic events and hemorrhagic events occurred in 8 patients (10.8%). Compared to patients without hemorrhagic-thrombotic events, patients with thrombotic events had higher fibrinogen (FIB) level, FDP level and lower ATIII activity, while patients with hemorrhagic events had lower white blood cell count and hemoglobin level, higher FDP level (P < 0.05). Patients with a JAK2V617F mutation were more likely to experience thrombotic events (P < 0.05). In addtion, patients with thrombotic events had higher TAT, PIC, TM, and t-PAIC levels than patients without hemorrhagic-thrombotic events (P < 0.05), whereas patients with hemorrhagic events had a lower median value in TAT and TM (no statistical difference, P > 0.05). Patients with higher TAT, TM and t-PAIC were more likely to experience thrombotic events (P < 0.05), and only TAT was positively correlated with thrombotic events (Spearman r =0.287, P = 0.019). TAT, PIC, TM, and t-PAIC combined with ATIII and FDP have a certain value for predicting thrombosis in patients with BCR/ABL1-negative MPN. These 6 parameters are worth further exploration as predictive factors and prognostic markers for early thrombotic events.

Capacidad pronóstica del dimero D en la predicción de mortalidad en pacientes con el diagnóstico de COVID-19

Introduction: SARS-CoV-2 infection can increase the risk of thrombosis. Studies associate D-dimer levels with COVID-19 mortality. Objective: To determine the prognostic capacity of D-dimer in predicting COVID-19 mortality in patients hospitalized in the Intensive Care Unit. Methods: A retrospective cohort study was conducted at the Centro Médico Naval from January to July 2021. A total of 324 adult patients with RT-PCR confirmed COVID-19 were included. D-dimer levels were measured upon admission using coagulation turbidimetry (Sysmex CS-5100). Sociodemographic variables, comorbidities, and clinical data were analyzed. Statistical analysis was performed using SPSS version 26, employing Chi-square tests, Fisher's exact test, Mann-Whitney U test, ROC, and Cox regression. Results: A cut-off point of 1.40 µg/mL for D-dimer values was determined, with a sensitivity of 80.9%, specificity of 86.4%, and an area under the curve (AUC) of 0.916 (95% CI: 0.884 – 0.947; p=0.016) for predicting COVID-19 mortality. Additionally, patients with D-dimer values greater than or equal to 1.40 µg/mL had an increased risk of death (adjusted HR = 6.545; 95% CI: 3.867 – 11.077; p&lt;0.001), independent of age, diabetes mellitus, arterial hypertension, ischemic heart disease, cerebrovascular disease, atrial fibrillation, chronic obstructive pulmonary disease, asthma, cancer, and thrombocytopenia. Conclusion: This study showed that admission D-dimer levels represent a reliable biomarker in evaluating the prognosis of COVID-19 patients.

Acute ischemic stroke and measurement of apixaban and rivaroxaban: an observational cohort implementation study

BackgroundTreatment with intravenous thrombolysis for acute ischemic stroke is contraindicated with intake of apixaban/rivaroxaban in the last 48 hours. Recent European Stroke Organization guidelines suggest that thrombolysis can be considered if anti-factor Xa activity (AFXa) is <0.5 × 103 IU/L with low-molecular-weight (LMWH) or unfractionated heparin (UFH) calibrated assays. Some centers also use apixaban/rivaroxaban-calibrated AFXa assays to identify patients with low drug concentrations. ObjectivesTo prospectively evaluate the first year of implementation of drug-calibrated AFXa assays at our center with 2500 yearly admittances with suspected stroke. MethodsSamples were analyzed on Sysmex CS-5100 instruments with Innovance anti-Xa reagents. Thrombolysis could be considered with drug concentrations <25 μg/L. Patients were registered in an institutionally approved quality register. Outcomes included (1) the number of patients receiving thrombolysis after drug measurement, (2) turn-around time for drug concentration measurements, and (3) sensitivity of LMWH/UFH AFXa to apixaban and rivaroxaban. ResultsApixaban or rivaroxaban was measured in 148 samples, and 4 patients who previously would have been ineligible for thrombolysis were treated with thrombolysis. In total, thrombolysis was administered in 123 patient episodes in the study period. The median turn-around time for the drug measurements was 38 minutes. Apixaban concentrations of 25 μg/L and 50 μg/L corresponded to LMWH/UFH AFXa of 0.13 and 0.27 × 103 IU/L, respectively. There were too few rivaroxaban results for regression analysis. ConclusionImplementation of apixaban and rivaroxaban measurements led to a small increase in the number of patients receiving thrombolysis. Excluding significant concentrations of apixaban or rivaroxaban using LMWH/UFH AFXa may be feasible.

Effects of Hemolysis on Routine Coagulation Tests when Tested on an Optical Coagulation Analyzer.

The Clinical and Laboratory Standards Institute recommends rejecting hemolyzed samples for coagulation tests. Sysmex CS5100 analyzer using an optical method is commonly used in laboratories. The influence of hemolysis on coagulation test has rarely been studied when tested on Sysmex CS5100. Determining this influence is necessary. Freshly collected samples were artificially hemolyzed to simulate the hemolysis processes. Coagulation tests were conducted on a Sysmex CS5100 coagulation analyzer. Detection values before and after hemolysis were compared. The results showed that after hemolysis detection, the prothrombin time (PT) statistically decreased, while the partial thromboplastin time (APTT) statistically increased. There were no significant differences in fibrinogen (Fg), thrombin time (TT), D-dimer (DD) or fibrinogen degradation products (FDPs). Antithrombin activity was elevated in hemolyzed samples. Although differences in PT and APTT were statistically significant, there was no need for rejection of hemolyzed samples due to insufficient clinical effects when tested on Sysmex CS5100 analyzer. Falsely elevated AT result may lead to misdiagnosis in patients with severe diseases, which should be carefully considered.

Establishment of reference intervals of platelet aggregation using inductors in blood plasma in children on the analyzer Sysmex CS-5100

Establishment of reference intervals of platelet aggregation using inductors in blood plasma in children on the analyzer Sysmex CS-5100

Analytical performance verification protocols and performance specifications of platelet-dependent von Willebrand factor activity testing

Objective: To investigate the analytical performance verification protocols and performance specifications of platelet-dependent von Willebrand factor (VWF) activity testing (VWF:GPIbM) for clinical laboratories. Methods: According to Clinical Laboratory Standards Institute (CLSI) documents and National Health Standard of China, the performance verification of VWF:GPIbM was designed and implemented using Sysmex CS-5100 instrument and its corresponding reagents. (1) Precision verification: Two commercial quality control samples (with normal and low activity levels) and three plasma pools (with activity range from 5.0% to 150.0%) were prepared. Each sample was tested five times daily for five consecutive days. The coefficient of variation (CV) of intra-and inter-run precisions were calculated, and the precision evaluation criterion was set according to package inserts. (2) Trueness verification: The calibrator was diluted to five reference materials with activity values of 5.2%, 31.2%, 62.4%, 104.0% and 138.7%, and each reference material was tested five times daily for five consecutive days. The bias between the measured value and the reference value was calculated, and the trueness evaluation criterion was set according to the total allowable error. (3) Linearity verification: Ten pooled plasmas with theoretical value range from 3.6% to 160.4% were prepared for the linearity verification of two calibration curves set by the manufacturer (i.e. low range and normal range calibration curve). Each pooled plasma was tested three times in a single run. The slope and R2 of linear regression of mean of measured value and theoretical value, as well as bias, were calculated, and the linearity evaluation criterion was set according to National Health Standard of China and package inserts. (4) Limit of quantitation verification: The calibrator was diluted to two reference materials with activity values of 3.3% and 2.7%, and each material was tested twelve times. The limit of quantitation evaluation criterion was set according to CLSI document. Results: The CVs of intra-and inter-run were 1.0%-2.5% and 1.1%-2.6%, respectively. The biases of trueness verification were -0.4%, 1.0%, -2.6%, 0.3% and -2.7%, respectively. The linearity verification results of low range (3.6%-31.8%) and normal range (28.4%-160.4%) showed that the slopes of regression equation were 1.021 7 and 0.996 2, respectively, R2 were 0.993 5 and 0.993 9, respectively, and the biases with 0-1.8% and -10.1%-0 of plasmas met the criterion. The biases ranged from -0.4% to 0.3% of test results in the verification of limit of quantitation met the criterion. Conclusion: The verification results of VWF:GPIbM assay for precision, trueness, linearity and limit of quantification meet the performance requirements indicated in the package inserts and the criteria set in this study, which can be taken as a reference of performance verification for the clinical laboratories.

Managing argatroban in heparin-induced thrombocytopenia: Aretrospective analysis of 729 treatment days in 32 patients with confirmed heparin-induced thrombocytopenia.

Managing argatroban in heparin-induced thrombocytopenia: Aretrospective analysis of 729 treatment days in 32 patients with confirmed heparin-induced thrombocytopenia.

Multicenter performance evaluation and reference range determination of a new one-stage factor VIII assay.

IntroductionWe conducted a multicenter evaluation of a new one‐stage factor VIII (FVIII) assay (Roche Diagnostics), intended for the quantitative assessment of FVIII activity. We evaluated the analytical performance of the FVIII assay on the cobas t 711 analyzer.MethodsExperiments performed at three laboratories used 3.2% citrated residual or commercially purchased plasma samples. Five human plasma pools and two controls were used to determine assay within‐run and within‐laboratory precision, and total reproducibility; coefficients of variation (CVs) and/or standard deviations (SDs) were calculated. Lot‐to‐lot variability and method comparison (vs Coagulation FVIII Deficient Plasma/Dade Actin FS Activated PTT reagent/Standard Human Plasma Calibrator on the Sysmex CS‐5100 analyzer; Siemens Healthineers) were evaluated by Passing–Bablok and Deming regression, respectively, and Pearson's r calculated. Assay‐specific reference range was determined using 199 fresh plasma samples from healthy adults, not receiving anticoagulants.ResultsAcross sites, SDs for repeatability were 0.016–0.046 for samples with ≤1.0 international units (IU)/dL FVIII activity; CVs were 0.9%–3.8% for samples with >1.0 IU/dl activity. Among samples with mean FVIII activity 0.344–133 IU/dl, good intermediate precision (SD 0.020 for samples with 0.344 IU/dl activity; CV 1.8%–4.7%) and good total reproducibility (CV 2.0%–13.3%) were observed. The FVIII assay showed excellent lot‐to‐lot variability (Pearson's r = .999) and good correlation with the comparator assay (Pearson's r = .993–.996). The reference range for FVIII activity was 82.2−218.0 IU/dl.ConclusionThe one‐stage FVIII assay demonstrated robust analytical performance on the cobas t 711 analyzer, supporting its use in routine laboratory practice.

Comparability of sample results and commutability of reference materials among different measurement procedures for protein C activity assays

Background and aimsSeveral types of measurement procedures (MPs) for protein C activity assays are currently available. Clinical sample (CS) results among different MPs should be comparable. The commutability of reference materials (RMs) is an essential requirement to achieve comparability of CS results. Materials and methodsConsidering the total error calculated using reliable biological variation (BV) data and external quality assessment (EQA) criteria, we chose the allowable limits of comparability and criterion of commutability. According to Clinical and Laboratory Standardization Institute EP9 and our previous studies, 92 CSs were used to evaluate the comparability among the three MPs (Sysmex CS-5100, IL ACL TOP 700, and STA-R Evolution). The difference in bias method recommended by International Federation of Clinical Chemistry and Laboratory Medicine was used to assess the commutability of six RMs, including World Health Organization (WHO) IS 02/342. ResultsThe compliance rates of CSs were 94.6–100% with the corresponding calibration mode. WHO IS, HemosIL calibration plasma, and candidate RMs, PC20201 and PC20202, were commutable between each pair of the three MPs. ConclusionIt is feasible to set the allowable limits of comparability and the criterion of commutability based on the BV and EQA criteria.

Laboratory methods for monitoring argatroban in heparin-induced thrombocytopenia.

The Summary of Product Characteristics for the direct thrombin inhibitor argatroban states monitoring should be by activated partial thromboplastin time (APTT), with a target range of 1.5-3.0 times the patients' baseline APTT. APTT may be influenced by coagulopathies, lupus anticoagulant and raised FVIII levels. Previous studies have shown sensitivity differences of APTT reagents to argatroban. Some recent publications have favoured the use of anti-IIa methods to determine the plasma drug concentration of argatroban. This study aims to compare the anti-IIa assays: Hemoclot thrombin inhibitor assay (HTI) and Ecarin chromogenic assay (ECA) alongside the APTT. Residual plasma of 25 samples from 8 patients (3 with COVID-19 and HIT: n=18, 5 with HIT: n=7) was tested at two sites: site A: Sysmex CS5100 by HTI and APTT (Actin FS and SynthASil), and also on Stago STA Compact Max: ECA and APTT (CK Prest); and site B: Stago STA R Max 2 by ECA and APTT (Cephascreen). Mean APTT ratio was 1.96 (Actin FS), 1.84 (SynthASil), 1.59 (CK Prest) and 2.48 (Cephascreen). Mean argatroban concentration by HTI was 0.60µg/mL and by ECA was 0.65µg/mL (site A) and 0.70µg/mL (site B). There was a poor correlation to HTI in APTT ratios (range r2 =.0235-0.4181) with stronger correlations between ECA methods to HTI (r2 =.8998 site A, r2 =.8734 site B). This study confirms previous publications on the unsuitability of APTT and expands this by being multisited and included APTT reagents that use mechanical clot detection. Both anti-IIa methods are more suitable.

Investigation of Relationship Between Coagulation Parameters and Embryonic Loss in Embryo Transferred Cows and Heifers

The aim of the study, the relationship between coagulation parameters and embryonic loss in embryo transferred (ET) cows and heifers wereevaluated. The animal material of this study consisted of 19 cows and 19 heif-ers on farms located in East Mediterranean Agriculture Research Institute in Adana. Blood samples were collected before the ET application from the recipient cows and heifers. Coagulation parameters measured included prothrombin time (PT), activated thromboplastin time (APTT), fibrinogen, thrombin time (TT), anti-thrombin-III (AT3) and D-dimer using by Sysmex® CA-7000 and activated protein C resistance, protein C and protein S using by Sysmex CS-5100. The pregnancy rate was found 5/19 (26.3%) and 5/19 (26.3%) in cows and in heifers, respectively (P&amp;gt;0.05). The em-bryonic mortality ratio in cows was 60% (3/5) and in heifers it was 40% (2/5). The differences of D-dimer levels be-tween pregnant and non-pregnant animals were significant (P&amp;lt;0.05).The APTT levels between the groups with preg-nancy and embryonic loss were significantly different (P&amp;lt;0.05). As a result, it was determined that there is a relation-ship between plasma D-Dimer levels and embryonic loss in cows that were transferred embryo.To the best of authors’ knowledge, this is the first study reporting the relationship between coagulation parameters and embryonic loss in ET cows and heifers.

Determination of reference ranges for automated platelet aggregometry on Sysmex CS‑5100 analyzer

Measurement of platelet function by light transmission aggregometry (LTA) using a special device – an aggregometer requires significant time and is time-consuming. In this study, an automated LTA procedure was evaluated to establish the reference ranges. On the Sysmex CS-5100 analyzer, aggregation measurements were performed using several agonists at a certain concentration: ADP (2 µmol/L); arachidonic acid (1 mmol/L); collagen (2 µg/ml); ristocetin (1.2 mg/ml); epinephrine (5 µmol/L). For each agonist, the maximum and final aggregation, the Lag phase and the Area under the aggregation curve were measured. Reference ranges for a standard panel of activators were determined on 40 samples of healthy subjects in the concentrations recommended by the International Society on Thrombosis and Haemostasis. A standard panel of agonists can be used on Sysmex CS series analyzers: ADP, arachidonic acid; collagen; ristocetin, epinephrine, so these devices can replace specialized aggregometers or perform platelet aggregation where this investigation is not currently performed.

Performance verification of a new fibrinogen assay.

Plasma fibrinogen (FIB), also known as factor I, plays a key role in the coagulation process. FIB testing in a clinical laboratory is crucial for coagulation screening and thrombolytic therapy. Here, we assessed the performance of a new, Chinese-made coagulation analyzer in the detection of FIB by comparing its precision and clinical feasibility with that of an imported system. Blood samples were collected and plasmas were separated. The precision, linearity, reference interval, carryover rate, clinically reportable range, and clinical applicability of the domestic coagulation analyzer for FIB assay were assessed and validated based on the documents or industry standards issued by the United States Clinical and Laboratory Standards Institute (CLSI). The within-batch precision CVs (coefficient of variation) for the low- and high-level specimens were 2.92% and 0.24%, respectively, while the total precision CVs were 3.05% and 1.81%, respectively; all of them met the experimental requirements. The linear range was validated to cover 1.0-6.5 g/L, and a good linear relationship was obtained within the measurement range (R2=0.9998). The reference interval was verified for adults and the carryover rate was also evaluated to be 0.68%. The clinically reportable range was 0.33-13.0 g/L. With a sample size of 180 cases, the methodological comparison showed a correlation coefficient (r) of 0.9886 between Mindray ExC810 and Sysmex CS5100. Furthermore, when the level of FIB was higher than 4.0 g/L or lower than 1.0 g/L, the 2 systems had an agreement rate of 100%. Mindray ExC810 has a good performance for FIB assay in terms of precision, linearity, reference interval, carryover rate, and clinically reportable range. Methodological study showed that Mindray ExC810 has good agreement with Sysmex CS5100 and meets the requirements of laboratory testing. Therefore, Mindray ExC810 is suitable for FIB assay in clinical laboratory.

Comparative evaluation of Rosner’s index (ICA) Vs Chang’s (% correction) as a screening test (mixing study)

Introduction: It is difficult to interpretate mixing study results (both screening & confirmatory) in presence of LAC. The main objective of this study is to define cut off values for ICA & % Correction which will reduce the no. of false positive & negative cases & will help in proper categorization of factor deficiency & inhibitors. This study also briefs about preanalytical errors & their correction Material and Methods: Rosner Index= × Cut offs ? 10 = Correction & ? 15 = Inhibitor Latest Sysmex CS-5100 auto-analyser was used to determine the Cut-offs. DRVVT mixing test ratio (Rosners index/ ICA) 1.15, % correction = 10, DRVVT Normalised ratio (NR) = 1.05. p value < 0>15 is 91.1% sensitive for inhibitor diagnosis & it could not categorise, 8% of total cases into factor deficiency /inhibitor. Discussion: Rosners index (ICA) as a confirmatory test for LA is more sensitive than % correction & DRVVT NR. Chang’s % correction with a cut off value of >70% is 85% sensitive in diagnosing factor deficiency & a cut off value of Conclusion: It can be safely concluded that Rosner index is better than % correction, both as a screening test & confirmatory test, to differentiate factor deficiency from inhibitor. This study results are in agreement with CLSI guidelines & favours the sequential order screen-confirm- & then if required mixing study as in case of screen and confirm analysis is not clear-cut and/or when other causes of prolonged clotting times are known or suspected The draw back with the mixing studies is that weak LAC can be missed. Though in this study Nijmegen is better than Bethesda in terms of sensitivity & specificity as the later gives false positive results, other studies has to be taken into consideration which shows that both the Bethesda & Nijgmegen technique have low specificity at higher inhibitor titre. If actual quantitation of high titre activity is required, then it is more reliable to estimate empirically plasma dilution that gives 50% inhib

Mutations in inherited fibrinogen disorders correlated with clinical features in the Chinese population

Two probands with unknown reasons for low fibrinogen activity were considered to investigate the association between mutations in inherited fibrinogen disorders (IFDs) and clinical features in the Chinese population. A routine coagulation test was conducted on a Sysmex CS5100 coagulation analyzer, and Sanger sequencing was employed to analyze mutations. A PubMed database search through May 2020 was performed to identify relevant studies regarding the congenital fibrinogen disorder epidemic in China. A common heterozygous missense mutation (c.1233G > A p.Arg35His), a novel heterozygous mutation (c.2014T > C p.Trp672Arg), and a novel homozygous mutation (c.16A > G p.Ile6Val) in the FGA gene were identified in two probands with dysfibrinogenemia. The global coagulation screening assay can distinguish four types of IFD, especially a ratio of Fib:Ag/Fib:C equal to 1.5, which can distinguish patients with hypofibrinogenemia from those with hypodysfibrinogenemia. A total of 81 mutations from 76 probands in 45 IFD families have been reported in the Chinese population. Arg35 in FGA and Arg301 in FGG were responsible for IFD in more than half of patients in the Chinese population. It is possible to distinguish four types of IFD by using a global coagulation screening assay. Mutations in FGA, FGB and FGG occur in different functional regions, and Arg changes account for more than 70% of patients with IFD in the Chinese population, especially Arg-Cys, which may be associated with severe clinical symptoms.

Clinical laboratory investigation of a patient with an extremely high D-dimer level: A case report

BACKGROUNDD-dimer, a soluble degradation product of cross-linked fibrin, is commonly used as an important marker for the diagnosis of disseminated intravascular coagulation and differential diagnosis of thrombosis. Herein, we present a geriatric case with an unusually elevated D-dimer level.CASE SUMMARYAn 82-year-old woman, admitted to the ward with a diagnosis of chronic heart failure, was noted to have a remarkably elevated D-dimer level, beyond the qualified range (> 100 mg/L), utilizing the Innovating D-dimer for Sysmex CS-5100 System™. However, no evidence, including clinical symptoms, radiographic evidence of thromboembolic disease, and parallel fibrinogen degradation product values, suggested that this patient was at high risk of thrombopenia. To confirm the discrepancy, a series of approaches including sample dilution, re-analysis via alternative methods, and sample treatment with blockage of specific heterophilic antibodies were performed. A remarkable disappearance of the elevated D-dimer values was observed in the samples after they were subjected to these approaches (4.49, 9.42, 9.06, and 12.58 mg/L, respectively). This confirmed the presence of heterophilic antibodies in this case. In addition, a reduction in cardiac output due to the presence of cardiac failure could also be responsible for the existence of a hypercoagulable state in this case.CONCLUSIONIn conclusion, the presence of heterophilic antibodies should be considered when an elevated D-dimer value is not in conformity with the clinical evidence, and a viral infection should be considered when interference by a heterophilic antibody exists.

Comparative Analysis of “ Screening vs Modified ” APTT based activated protein C resistance (APCR) assay in the diagnosis of Factor V leiden mutation

APCR is a hemostatic disorder characterized by increased risk of deep vein thrombosis and pulmonary embolism. Factor V Leiden mutation accounts for 95% of APCR cases &amp; the remainder are due to acquired causes like patients on vitamin k antagonist therapy, direct oral acting anticoagulants, Lupus anticoagulant &amp; oral contraceptive pills. T he main objective of this study is to compare the sensitivity of APTT based APCR test vs Modified APTT with pre -dilution in F actor V-deficient plasma for diagnosis of Factor V leiden mutation &amp; to formulate a systematic diagnostic algorithm for interpretation of APCR tests. The Coagulometer used for APCR test is Sysmex CS-5100. APTT reagent used is Pathrombin SL supplied by seimens. All data were expressed as Mean ± SD. Statistical analysis was done using unpaired students t test &amp; a P value &amp;#60;0.05 is considered as statistical significance. : A total of 150 cases of APCR (100 cases of factor V Leiden mutation confirmed by PCR &amp; 50 non carrier /acquired cases) were studied retrospectively. Sensitivity of screening APTT base d APCR for detection of factor V Leiden mutation is 78% &amp; for non carrier state it is 82%. Sensitivity of modified APTT with pre- dilution in FV-deficient plasmafor detection of factor V Leiden mutation is 93% &amp; for noncarrier state (acquired) is 34%. Screening APTT test is increased in Activated protein C resistance due to factor V Leiden mutation as well as acquired causes like patients on direct acting oral anticoagulants, warfarin, lupus anticoagulants and oral contraceptive pills which are independent risk factors of venous thrombosis. Modified APTT with predilution in FV-deficient plasma (1:4) is more sensitive than Screening APTT based APCR test in diagnosis of Factor VLeiden mutation &amp; this test can distinguish homozygous &amp; heterozygous states from normal individuals.

Identification of and solution for false D-dimer results.

BackgroundClinically, D‐dimer (DD) levels are mainly used to exclude diseases such as deep venous thrombosis (DVT). In clinical testing, DD assays can be subjected to interference that may cause false results, which directly affect the clinical diagnosis. Our hypothesis was that the 95% confidence intervals (CIs) of the fibrin degradation product (FDP)/DD and fibrinogen (Fib)/DD ratios were used to identify these false results and corrected via multiple dilutions.MethodsIn total, 16 776 samples were divided into three groups according to the DD levels detected by Sysmex CS5100 and CA7000: Group A, DD ≥ 2.0 μg/mL fibrinogen equivalent unit (FEU); group B, 0.5 < DD < 2.0 μg/mL FEU; and group C, DD ≤ 0.5 μg/mL FEU. The 95% CIs of the FDP/DD and Fib/DD ratios were calculated. Six abnormal DD results were found according to the 95% CIs. For verification, we performed multiple dilutions, compared the results with those of other instruments, and tested the addition of heterophilic blocking reagent (HBR).ResultsThe median and 95% CI of the FDP/DD ratio were 3.76 and 2.25‐8.15 in group A, 5.63 and 2.86‐10.58 in group B, 10.23 and 0.91‐47.71 in groups C, respectively. For the Fib/DD ratio, the 95% CIs was 0.02‐2.21 in group A, 0.68‐8.15 in group B, and 3.82‐55.27 in groups C. Six abnormal results were identified after multiple dilutions, by comparison with other detection systems, and after HBR addition.ConclusionsThe FDP/DD ratio is more reliable for identifying false results. If the FDP/DD ratio falls outside the 95% CI, it should be verified by different methods.