ABSTRACT
Objective@#To establish a set of rules for autoverification of blood analysis, in order to provide a way to validate autoverification rules for different analytical systems, which can ensure the accuracy of test results as well as shorten turnaround time (TAT) of test reports.@*Methods@#A total of 34 629 EDTA-K2 anticoagulated blood samples were collected from multicenter cooperative units including the First Hospital of Jinlin University during January 2017 to November 2017. These samples included: 3 478 cases in Autoverification Establishment Group, including 288 cases for Delta check rules; 5 362 cases in Autoverification Validation Group, including 2 494 cases for Delta check; 25 789 cases in Clinical Application Trial Group. All these samples were analyzed for blood routine tests using Sysmex XN series automatic blood analyzers.Blood smears, staining and microscopic examination were done for each sample; then the clinical information, instrument parameters, test results and microscopic results were summarized; screening and determination of autoverification conditions including parameters and cutoff values were done using statistical analysis. The autoverification rules were input into Sysmex Laboman software and undergone stage Ⅰ validation using simulated data, and stage Ⅱ validation for post-analytical samples successively. True negative, false negative, true positive, false positive, autoverification pass rate and passing accuracy were calculated. Autoverification rules were applied to autoverification blood routine results and missed detection rates were validated, and also data of autoverification pass rate and TAT were obtained.@*Results@#(1)The selected autoverification conditions and cutoff values included 43 rules involving WBC, RBC, PLT, Delta check and abnormal characteristics. (2)Validation of 3 190 cases in Autoverification Establishment Group showed the false negative rate was 1.94%(62/3 190)(P<0.001), autoverification pass rate was 76.74%, passing accuracy was 97.47%; Validation of 2 868 cases in Autoverification Validation Group, the false negative rate was 3.38%(97/2 868)(P=0.002), autoverification pass rate was 42.26%, passing accuracy was 92.00%; Validation of Delta check on 288 cases in Autoverification Establishment Group and 2 494 cases in Autoverification Validation Group showed the false negative rates were respectively 1.39% and 2.61%(P<0.001). (3)Three hospitals adopted these rules of autoverification for 25 789 blood routine samples, and found that the average TAT of blood routine test reports were shortened by 24min, 32min and 7min respectively, the rate of samples reported within 30min were elevated by 33%, 53% and 7%. The autoverification pass rates were 72%-74%.@*Conclusions@#The application of this set of 43 autoverification rules in blood sample analysis can ensure test quality while shortenTAT and improve work efficiency. It is worth pointing out that for the same analytical systems in this research, validation is necessary before application of this set of rules, and periodic validation is required during application to make necessary adjustment; for different analytical systems, as this research provide a way to establish autoverification rules for blood routine tests.Clinical labs may establish their own suitable autoverification rules on the basis of technological parameters. (Chin J Lab Med, 2018, 41: 601-607)
ABSTRACT
ObjectiveTo evaluate the improvement on test performance of UniCel DxH 800 automated hematology analyzer for complete blood count (CBC) by detecting its performance indicators and comparing the differences of the results with LH 750 hematology analyzer and ADVIA 2120 hematology analyzer.MethodsThe precision,carryover and linearity of UniCel DxH 800 in measurement of CBC were evaluated by using fresh blood samples and instrument quality control of products.To evaluate the accuracy of leukocyte differential count and reticulocyte count with the microscopic method as the “gold standard”.To calculate the bias and correlation between the results measured by LH 750,ADVIA 2120 and UniCel DxH 800 hematology analyzers and compare these three instruments on the validity of the alarm in abnormal cells.ResultsIntra-precision:The coefficient of variation (CV) of the results of RBC,Hb and MCV were less than 0.5％,the CV of WBC and PLT results were less than 1.5％.Inter-precision:the CV of the parameters above were less than 2.5％.The carryover rate of WBC,RBC,Hb,MCV and PLT were less than 0.51％.In the concentration range covered by clinical samples,the correlation coefficients between the measured values and theoretical value in testing WBC,RBC,Hb and PLT were greater than 0.999 ( P ＜0.01 ).The measurement results of WBC,RBC,Hb,MCV and PLT hy UniCel DxH 800,ADV1A 2120 and LH 750 hematology analyzers have good correlation (r ＞ 0.973,P ＜ 0.01 ).Correlation of reticulocyte count between the UniCel DxH 800 hematology analyzer and microscolpic method was significant (r =0.920,P ＜0.01 ).Correlation of leukocyte differential count about the grauulocytes, lymphocytes and eosinophils between the UniCel DxH 800 hematology analyzer and microscopic method was good (r =0.914,0.900 and 0.725,P ＜0.01 ),followed by monocytes ( r =0.612,P ＜0.01 ),which were better than the LH 750 with similar detection principle.The UniCel DxH 800 hematology analyzer demonstrated higher sensitivity (96.6％ ) for the alarm of abnormal cells and achieved a lower false-negative rate (2.5％ ).Meanwhile,the sensitivity of the neutrophil nuclei left shift was higher (90.5％ ) and the false-negative rate (5.0％) was lower.ConclusionsThe UniCel DxH 800 hematology analyzer for complete blood count shows advantages of high precision,low carryover rate and wide linear range.The results detected by the UniCel DxH 800 hematology analyzer have good correlation with the LH 750 and ADVIA 2120.
ABSTRACT
Objective To explore the values of potential clinical application ofsingle tube/ten colorsflow cytometry for leukocyte differential count in peripheral blood.Methods Utilizing multiple monoclonal antibody combinations and the vavious logical gating strategies,the single tube/12 antibodies with no-wash method for the leukocyte differential count in peripheral blood were determined by using 10 colors flow cytometry.Leukocyte differentials of 142 peripheral blood samples were determined by both Beckman-Coulter LH750 hematology analyzer and 10 colors flow cytometry.The results were then compared to standard microscopic examination as a reference method.The clinical diagnostic efficiency ofsingle tube/10 colorsflow cytometry was calculated.The correlations between standard microscopic cytology,single tube/10 colorsflow cytometry and the hematology analyzer were determined.In addition,the clinical diagnosis efficiency for blast counts ofsingle tube/10 colorswere compared to the results determined by BD FACS Calibur flow cytometer.Results The leukocyte differentials were correlated well between the single tube/10 colorsflow cytometry and standard microscopic cytology(r>0.700,P<0.01) except for basophils.The correlations with neutrophilic granulocytes,lymphocytes,immature granulocytes and blasts were superior(r=0.972,0.951,0.801,0.912,respectively,P<0.01).When 1% was selected as the cut-off point for immature granulocytes determined by standard microscopic cytology,the sensitivity and the specificity ofsingle tube/10 colorsflow cytometry were 92%(57/62) and 79% (63/80),respectively.When 0.5% was selected as the cut-off point for blasts detected by standard microscopic cytology,the sensitivity and the specificity were 99% (67/68) and 92% (68/74).Using the immunophenotyping results from BD FACS Calibur as a standard,the sensitivity for detecting blasts bysingle tube/10 colOrsflow cytometry was 100% (40/40),the specificity was 91% (10/11),the positive predictive value was 98% (40/41),the negative predictive value was 100% (10/10) and the accuracy was 98% (50/51).Conclusions Thesingle tube/10 colorsflow cytometry has a excellent correlation with the standard microscopic cytology when applied on leukocyte differential count in peripheral blood.It may potentially use as a subsequent method for verification of abnormal results of complete blood cell count in the future.
ABSTRACT
Objective To study the pathological characteristics of leukocyte myeloperoxidase (MPO) deficiency and clinical laboratory diagnostic strategy for this disease. Methods The Bayer ADVIA 120 blood cell analyzer differentiate leukocyte and detect myeloperoxidase index (MPXI) . The leukocyte morphology and differentiating count on blood smear by Wright’s stain were finished. The peroxidase positive cell percentage and score were counted by peroxidase stain. The expressive levels of leukocyte MPO antigen were measured by flow cytometric monoclonal antibodies method.Results The prevalence of mild neutrophil MPO deficiencies was 2.61%, and partial neutrophil MPO deficiencies was 0.39% in 5 761 in-patients. The significant changes in the dot plot from ADVIA 120 blood cell analyzer were seen in 3 patients with MPO deficiencies, and MPXI,MPO activities and MPO antigen levels of the patient’s neutrophils and monocytes decteased remarkably,but there were normal levels in eosinophils.Conclusion Neutrophil MPO deficiencies were not a rare disorder,but the mild deficiency cases were seen usually.The low activity of MPO is an important evidence for MPO deficiencies diagnosis.The Bayer ADVIA 120 blood cell analyzer can be used simply and fleetly for screening MPO deficiencies in routine hematology laboratory.The peroxidase stain of blood smear is an improtant diagnostic method for MPO deficiencies.