1.Evaluation of NT-proBNP assay performance on electro-chemiluminescence immunoassay system
Xiuming ZHANG ; Dongmei WEN ; Weijia WANG ; Fei LI ; Lijuan KAN ; Haizhong YAN ; Minghuan SUO ; Nengliang OUYANG
Chinese Journal of Laboratory Medicine 2011;34(12):1152-1157
ObjectiveTo evaluate analytical performance of NT-proBNP on Electro-Chemiluminescence Immunoassay system.MethodsThe precision,accuracy,limit of blank ( LoB ),limit of detection (LoD),functional sensitivity (FS),analytical measure range (AMR),maximal dilution rate,clinical reportable range(CRR) and the analytical anti-interference ability of NT-proBNP were evaluated according to EP documents issued by CLSI and related references.The analytical performance data were compared to quality standards declared by the manusfacturers.According to CLSI C28-A2,80 healthy volunteers,aged from 18 to 74, were chosen and divided into 4 groups on average for biological reference intervals verification.Results The within-run CV and total CV were 1.1% -2.2%and 1.5% -2.9% respectively.The deviations from controls distributed by National Center for Clinical Laboratory and affiliated calibrators were 2.7% -5.9% and 2.7% -7.5%,respectively.The results of LoB,LoD and FS were 2.5,7.8 and 8.8 pg/ml,respectively.AMR was 8 -35 126 pg/ml,and the most suitable dilution rate was 1∶ 2,so the CRR was 9 -70 252 pg/ml.428 μmol/L bilirubin,2 g/L haematoglobin and 2 200 FIU chyle didn't interfere with the NT-proBNP assay.Moreover,almost all the data from different age groups were in the range of biological reference intervals declared by the manusfacturers, except one test data (167 pg/ml).Conclusions The analyticalperformance of NT-proBNP analyzed on Roche Cobas E601electrochemiluminescence immunoassay systemisconsistentwiththestandarlswhichmanufacturershas proclaimed.The establishment of LoD,FS,maximal dilution and CRR for NT-proBNP assay could provide the quality assurance for clinical use and the biological reference intervals declared by manusfacturers could meet the clinical needs.
2.The relationship between glucose-6-phosphate dehydrogenase deficiency and type 2 diabetes
Lijuan KAN ; Jingjing LI ; Xiuming ZHANG ; Dongmei WEN ; Minghuan SUO ; Weijia WANG ; Jianyang WU
International Journal of Laboratory Medicine 2015;(16):2297-2300
Objective To explore the relationship between glucose-6-phosphate dehydrogenase deficiency and type 2 diabetes and to provide reference for clinical diagnosis,monitoring and treatment of Type 2 diabetes.Methods Subjects were selected from our hospital,including 173 cases of healthy volunteers assigned to the control group;1 95 cases with type 2 diabetes conforming to the diagnostic criteria of WHO were assigned to the diabetic group.97 cases were diagnosed with glucose-6-phosphate dehydrogenase deficiency in our hospital,of whom 82 cases were assigned to simple glucose-6-phosphate dehydrogenase deficiency group,and 1 7 cases were assigned to the diabetes with glucose-6-phosphate dehydrogenase deficiency group.The correlation of glucose-6-phos-phate dehydrogenase activity and diabetes was measured by each detected value.Results Compared with the control group,the glu-cose-6-phosphate dehydrogenase activity and RBC count in diabetic group were higher(P <0.05).Positive correlations between glu-cose-6-phosphate dehydrogenase activity and RBC count in the two groups were significant(P <0.05).HbA1c and FBG showed a significant positive correlation in the control group,diabetic group and diabeties with glucose-6-phosphate dehydrogenase deficiency group(P <0.05).But there was no significant correlation in the glucose-6-phosphate dehydrogenase deficiency group.The rate of screening for glucose-6-phosphate dehydrogenase deficiency in diabetes group was 3.6%,and the rate in the control group was 1. 1%.When HbAlc≥6.5%,the rate of screening for glucose-6-phosphate dehydrogenase deficiency in the diabetes group was signifi-cantly higher than that in the control group (χ2 =4.239,P =0.039).Conclusion The level of HbA1c is discordant with that of blood glucose in diabetic patients with glucose-6-phosphate dehydrogenase deficiency group.Diabetes leads to the increasement of the rate of glucose-6-phosphate dehydrogenase deficiency.The glucose-6-phosphate dehydrogenase activity of diabetic patients with non-glucose-6-phosphate dehydrogenase dificiency is higher than that of the normal group.It may be associated with the level of RBC or increase of compensatory.Further more,glucose-6-phosphate dehydrogenase activity may be a good indicator for controlling diabetes,which remains to be further studied.
3.Performance verification of HbA1c determination by using affinity chromatography
Jiasi ZHOU ; Dongmei WEN ; Ying CHEN ; Quanzhong XU ; Minghuan SUO ; Lijuan KAN ; Yaqiong CHEN ; Xiuming ZHANG
International Journal of Laboratory Medicine 2014;(17):2359-2361
Objective To evaluate the precision,accuracy,linear range and anti-interference performance of HbA1c assay by u-sing Primus Trinity Ultra2 automated analyzer.Methods According to Document EP published in 2004 by American Clinical and Laboratory Standards Institution(CLSI)and relative literatures,the precision,accuracy,linear range and anti-interference perform-ance were evaluated.Results The within-run and between-run CVs of HbA1c determination were both less than that announced by manufacture.In the tests of samples with certain concentrations,all the results were within the verification range respectively.In the linear verification,regression equation between the theoretical and measured values demonstrated that r2 >0.95,and a value was within the range of 0.97-1.03.For Primus Trinity Ultra2 the limit of interference effect didn′t exceed the allowable error at the medical decision concentrations.Conclusion The precision,accuracy,linear range and anti-interference was evaluated of the Primus Trinity Ultra2 automating HbA1c all could meet the manufacture′s declaim and the clinical needs.
4.The interference evaluation of hyperlipidemia and hyperbilirubinaemia to HbA1c measurement with IE-HPLC method
Jinli XIAO ; Xiuming ZHANG ; Shengnan XU ; Minghuan SUO ; Quanzhong XU ; Yaqiong CHEN ; Jianyang WU ; Man LI ; Lijuan KAN ; Dongmei WEN
International Journal of Laboratory Medicine 2015;(17):2492-2494
Objective To investigate the interference of hyperlipidemia and hyperbilirubinaemia to HbA1c measurements by ion‐exchange high‐performance liquid chromatography(IE‐HPLC) method .Methods Fresh whole‐blood samples collected with EDTA‐K2 anticoagulant tubes were divided into four groups :control group(HbA1c<6 .2% ) ,diabetes group(HbA1c≥6 .2% ) ,hyperlipi‐demia group(TG 3 -20 mmol/L);hyperbilirubinaemis group (TBIL 21 -549 μmol/L) .HbA1c of these samples were measured with affinity chromatography(AC‐HPLC) and IE‐HPLC respectively .Results When HbA1c≤18 .7% ,r=0 .993 ;95% confidence interval(CI) of HbA1c results by using IE‐HPLC method was -0 .71 -0 .89 ;coefficient of variation was -5 .8% -6 .8% ;P=0 .198 and the difference was not statistically significant .When HbA1c< 16 .3% ,r= 0 .997;95% CI of HbA1c results with IE‐HPLC method is -0 .31-0 .67;coefficient of variation was -5 .8% -4 .3% .P=0 .000 and the difference was statistically signifi‐cant .No interference was detectded with the results ;When HbA1c was 16 .3% -18 .7% ,positive bias was observed with the re‐sults .When TG≤20 .78 mmol/L ,r=0 .995;95% CI of HbA1c results with IE‐HPLC method was -0 .26-0 .50 ;coefficient of var‐iation was -5 .5% -5 .8% .P=0 .000 and the difference was statistically significant .No interference was detectded with the re‐sults;When TBIL≤549 .3 μmol/L ,r=0 .990 ;95% CI of HbA1c results with IE‐HPLC method was -0 .08 -0 .63;coefficient of variation was -14% -4 .1% .P=0 .000 and the difference was statistically significant .When TBIL≤342 .1 μmol/L ,r= 0 .994 ;95% CI of HbA1c results with IE‐HPLC method was -0 .09-0 .50;coefficient of variation was -5 .5% -4 .1% .No interference was detectded with the results .When TBIL was 380 .7-549 .3 μmol/L ,negative bias was observed with the results .Conclusion Our data indicated that HbA1c measurement with IE‐HPLC method could resist the interference of hyperlipidemia;When TBIL≤380 .7 μmol/L and HbA1c<16 .3% ,the results could meet the needs of general clinical detection .Clinical staff should choose more specific HbA1c measurement method according to the patient's condition .
5.The influence of beta-thalassemia minor on glycosylated hemoglobin four measuring systems
Minghuan SUO ; Dongmei WEN ; Xiuming ZHANG ; Jianyang WU ; Yaqiong CHEN ; Quanzhong XU ; Man LI ; Ting HU ; Jinli XIAO ; Decai ZHANG ; Shengnan XU
Chinese Journal of Laboratory Medicine 2015;(10):691-695
Objective To investigate the Influence of beta-thalassemia minor on four different HbA1c detection systems.Methods All 65 blood samples from March 2014 to August 2014 were collected from Zhongshan Hospital of Sun Yat-sen University , and divided to normal control group ( 40 cases ) , no diabetic group(20 cases) and diabetic group (5 cases) combining with beta-thalassemia minor.The fresh mixed whole-blood samples were used for transferring value-assignment in order to improve the comparability of Bio-Rad variant ⅡTurbo, Primus Ultra2 ,Roche Modular PPI to Bio-Rad Variant Ⅱwhich was NGSP Ⅰlaboratory certificated.The whole-blood concentration of HbA 1c were measured by four detection systems . Differences between normal control group and no diabetic group were compared using the Independent Samples T Test.Then Taking the Primus Ultra 2 as comparable system and others as experimental system ,the HbA1c results from no diabetic group and diabetic group were compared by the standardization NGSP Ⅰlaboratory and statistical techniques of consistency test .Results Compared with Variant Ⅱ detection system, after transferring value-assignment, deviations of Variant Ⅱ, Modular PPI and Variant Ⅱ Turbo were -6%to +6%.The HbA1c testing results from normal control group and no diabetic group had no statistical significance (P>0.05).Linear regression analysis demonstrated that the correlation coefficient of Primus Ultra2 with Variant Ⅱ, Modular PPI, VariantⅡTurbo were 0.995, 0.999 and 0.995, respectively (P<0.01).The percentage deviation of the reference system and experimental system was -6.0% to+6.0%.Conclusion There was no obviously significant influence of beta-thalassemia minor on Bio-Rad Variant Ⅱ,Bio-Rad variant ⅡTurbo,Primus Ultra2,Roche Modular PPI detection systems.
6.Establishment and application of the autoverification system in laboratory clinical chemistry and immunology laboratory
Dongmei WEN ; Xiuming ZHANG ; Weijia WANG ; Decai ZHANG ; Yongli FAN ; Ting HU ; Minghuan SUO ; Man LI ; Yaowen ZHENG ; Lishan WANG ; Hanpeng DAI ; Jian LI
Chinese Journal of Laboratory Medicine 2018;41(2):141-148
Objective To improve the efficiency of result reporting and ensure the accuracy of the results by establishing autoverification system in Clinical Chemistry and Immunology Laboratory.Methods The study followed the requirements of the Clinical Laboratory Standards Institute(CLSI)AUTO-10A and ISO 15189:2012.In addition,seven categories of verification rules were encoded using the autoverification function of the CentraLink?Data Management System on the Aptio?Automation platform.These rules included Clinical Diagnostic Standard(CS), Sample Status(SS), Quality Control Severity(QS), Instrument Error Flags Severity(IS), Normal Severity(NS), Delta Check Severity(DS), and Logical Assessment Standard(LS).Various modules of Aptio Automation,laboratory information system(LIS)and hospital information system(HIS)were integrated using the CentraLink system to establish the autoverification system.Results The autoverification system was set up and tested from August 2015 to April 2016.In total, the system ran 4 496 425 tests on 366 180 chemistry specimens.The overall autoverification rate for tests performed increased from 53.4% to 87.0%.Glucose had the highest rate (98.3%)while CKMB had the lowest rate(63.6%).Average TAT for result verification decreased by 97.7%,from 46.3 minutes to 3.7 minutes.The system ran 410,040 tests on 160 119 chemiluminescence specimens.The autoverification rate for tests performed increased from 40.2%to 89%.C-P had the highest rate(98.4%)while A-TPO had the lowest rate(58.7%).Average TAT for result verification decreased by 77.4%,from 14.6 minutes to 3.3 minutes.From May 2016 to January 2017(when autoverification was employed),compared with the same period in 2014(when manual verification was employed),the following changes were observed with no increase in staff capacity:a)Volume of routine chemistry tests increased by 46.4%,and median TAT for tests decreased by 41.9%, from 118 minutes to 83 minutes; b)Volume of chemiluminescence tests increased by 24.5%and median median TAT for tests decreased by 52.4%, from 131 minutes to 86 minutes;c)Median TAT for critical values decreased by 50.5%; d)Rates of tests that did not go through autoverification were 88.2% for NS,6.05% for SS, 2.40% for DS,2.00% for LS, 0.97%for IS,and 0.43% for CS; e)Rates of abnormal specimen status identified by Aptio Automation were 7.13‰for jaundice,5.39‰ for blood lipids,2.20‰ for hemolysis,0.17‰ for barcode error, and 0.15‰ for insufficiency;f)Error rate decreased to 0.00%;and g)staff satisfaction increased from 85%to 100%.Conclusion Autoverification of results by using the CentraLink Data Management System can achieve quality control over the entire process of clinical laboratory testing, ensure accuracy of test results, improve work efficiency, decrease TAT, minimize the error rate, avoid skill variation of staff, reduce the pressure of performing manual verification,and improve medical security.
7.Effect of double heterozygous hemoglobin on the results of different glycosylated hemoglobin detection systems
Minghuan SUO ; Dongmei WEN ; Weijia WANG ; Zizhi DONG ; Xia WANG ; Ting HU
Chinese Journal of Clinical Laboratory Science 2019;37(3):167-172
Objective:
To investigate the effects of glycosylated hemoglobin A1c (HbA1c) from the patients with double heterozygotes Hb Q-H and Hb J-Bangkok combined with β-thalassemia on the results of different HbA1c detection systems.
Methods:
Blood samples from 20 healthy adults and 20 patients with type 2 diabetes mellitus (T2DM) were collected to assess the results of five glycosylated hemoglobin detection systems. Blood samples from one Hb Q-H patient and one Hb J-Bangkok patient with β-thalassemia were also collected, and they were performed hemoglobin capillary electrophoresis with Capillarys2 and globin gene analysis by gap-PCR, PCR-RDB and DNA sequencing. The levels of HbA1c in all samples were detected by BioRad VARIANT Ⅱ (VⅡ), BioRad VARIANT ⅡTurbo2.0 (V Ⅱ-T2.0), Capillarys 2 Flex Piercing (C2FP), Primus Ultra2 (Ultra2) and Roche PPI 800 (PPI 800) glycosy lated hemoglobin detection instruments, respectively. For the samples with double heterozygotes, the levels of HbA1c were detected for 3 times each sample, and the results were preserved and analyzed.
Results:
The genotype of the Hb Q-H sample was --α QT /--SEA;β N /β N , and HbA1 CD74 G>C mutation occurred in globin α1 chain, forming Hb Q-Thailand hemoglobin variant without normal α-globin peptide chain. The genotype of Hb J-Bangkok combined with β-thalassemia was αα/αα;βCD56/βCD41-42, and the point mutation of GGC>GAC occurred at codon 56 of globin β-chain, forming Hb J-Bangkok hemoglobin variant without normal β-globin peptide chain. For the Hb Q-H sample, HbA1c results were reported by 3 of 5 HbA1c detection systems. The chromatograms of VⅡ and VⅡ-T2.0 detection systems were obviously different from normal chromatograms, and HbA1c results were not reported. However, the chromatograms of the C2FP system were similar to normal chromatograms, and the result of HbA1c was 3.7%. The Ultra2 system and PPI system reported the HbA1c results, 5.3% and 5.7%, respectively, without abnormal alarm. For the Hb J-Bangkok with β-thalassemia sample, HbA1c results were also reported by 3 of 5 HbA1c detection systems. The chromatograms of VⅡ and Sebia detection systems were obviously different from normal chromatograms, and HbA1c results were not reported. However, the chromatograms of VⅡ-T2.0 system were different from normal chromatograms, and a P4 peak (84.9%) was found. The HbA1c result was reported as 4.7%. The Ultra2 system and PPI system reported the HbA1c results, 4.7% and 3.8%, respectively, without abnormal alarm.
Conclusion
The samples from the Hb Q-H patient and the Hb J-Bangkok patient with β-thalassemia do not contain normal HbA, and there should be no HbA1c results. The chromatograms of VⅡ and VⅡ-T systems are obviously abnormal, indicating that the results can not be reported. The C2FP system is interfered obviously by Hb Q-H, but reports the HbA1c results, while it does not report the HbA1c results of Hb J-Bangkok combined with β-thalassemia. Both of Hb Q-H and Hb J-Bangkok have obvious interference to PPI and Ultra2 detection systems.