TOSOH HLC-723 G8全自动糖化血红蛋白分析仪性能评价

目的对以离子交换高效液相色谱法（HPLC）为原理的TOSOHHLC-723G8全自动糖化血红蛋白分析仪（简称HLC-723G8）检测全血糖化血红蛋白（HbA1c）的性能进行评价。方法对HLC-723G8测定HbA1c的精密度、相关性、线性、携带污染进行评价,并检测54例健康体检者的HbA1c进行参考区间验证。结果HLC-723G8测定HbA1c低、高水平批内变异系数（cv）分别为0．00％、0．47％,批间CV分别为0．76％、0．31％;HLC-723G8与HLC-723G7全自动糖化血红蛋白分析仪测定HbA1c的结果呈明显相关（F2=0．999,P〈0．001）,预期偏倚为0．06,相对偏倚值为0．83％,偏差符合率为100％;在5％～12％范围内线性良好（r2=0．9996,P〈0．001）;高值标本对低值标本的结果无明显携带污染（携带污染率为1．12％）;54名健康人群的HbA1c测定结果为4．7％-6．3％,在厂家提供的参考区间内。结论HLC-723G8测定HbA1c的性能良好,可在临床使用。     

Unanticipated error in HbA1c measurement on the HLC-723 G7 analyzer

ObjectivesInvestigation of falsely elevated HbA_1c measurements on the HLC-723 G7 analyser.Design and methodsComparison of HbA_1c in blood samples that were diluted either in hemolysis reagent or water.ResultsHbA_1c results became falsely elevated when samples were diluted in hemolysis reagent, but not in water. QC-procedures failed to detect this error as calibrator and QC samples were manually diluted in water, according to manufacturer's instructions, whereas patient samples were automatically diluted using hemolysing reagent. After replacement of the instruments' sample-loop and rotor seal comparable HbA_1c results were obtained, irrespective of dilution with hemolysing reagent or water.ConclusionThis case illustrates the importance of treating calibrator and QC materials similar to routine patient samples in order to prevent unnoticed drift in patient HbA_1c results.     

Evaluation of the hemoglobin A1c-analyzer TOSOH HLC-723 G7

The TOSOH HLC-723 G7 is a compact analyzer designed for the measurement of HbA1c under routine laboratory conditions. The analyzer has an automatic blood tube supply and positive sample identification. Samples are transported automatically via racks in a continuous-load mode, cap piercing is optional. Tests devoted to the assessment of reproducibility and accuracy of analytical results indicated that over a test period of 17 days, the intra-assay variation (CV) was 1.79%, and the inter-assay variation 2.60%, respectively. A comparison with the predecessor model G5 showed a very good correlation (r = 0.997, y = 1.0041x - 0.00172; n = 149). The presence of high triglyceride, bilirubin or urea concentrations in patient samples did not influence the analytical precision. The labile HbA1c fraction (L-A1c) is clearly separated during chromatography and thus does not compromise HbA1c analysis. With a protocol of 1.2 minutes, the TOSOH G7 is a very fast analyzer, designed for laboratories with a high throughput of samples.     

Analytical evaluation of the Tosoh HLC-723 G7 automated HPLC analyzer for hemoglobin A2 and F determination

OBJECTIVES: The analytical performance of a new automated HPLC system (Tosoh HLV-723 G7) for Hb A(2) and Hb F quantification in blood was studied. DESIGN AND METHODS: Hb A(2) and Hb F measurements were studied for imprecision, linearity, carry-over, interferences and sample concentration effect. Method comparison study was performed with the Bio-Rad Variant II HPLC system. Hb F results were also compared with those obtained by the alkaline denaturation test. The detection of some common Hb variants was also studied. RESULTS: Hb A(2) within-run and between-run CVs were found between 0.8-2.2% and 2.9-7.2%, respectively, while CVs for Hb F were up to 10.0% in normal and between 1.9-5.3% at more clinically relevant Hb F concentrations (>1.5%). Comparison study with Bio-Rad Variant II for Hb A(2) determination showed good correlation but highlighted calibration differences. The following results were obtained in two different laboratories: y = 1.163x - 0.52, r = 0.9918, n = 144 (Lab A); y = 1.060x - 0.40, r = 0.9920, n = 93 (Lab B). With regard to the determination of Hb F, the measurements performed by the tested method was found to correlate well with the alkaline denaturation test (y = 1.0138x - 0.36, r = 0.9842, n = 20) and with the Variant II HPLC system (y = 0.812x + 0.52, r = 0.9835, n = 110). An excellent linearity (r = 0.999) was found for both Hb A(2) and Hb F in the range 0.8-19%. Hb S, Hb C and Hb D can be presumptively identified by the assigned retention time windows. CONCLUSION: The new analyzer Tosoh HLV-723 G7 was found to be a reliable method for Hb A(2) and Hb F quantification and for the presumptive identification of some common Hb variants.     

Effect of HbS in the determination of HbA2 with the Biorad Variant II analyzer

OBJECTIVES: The effect of the presence of HbS in the determination of HbA2 using the Biorad Variant II analyzer. DESIGN AND METHODS: The effect of HbS presence in the samples was quantified using the HELENA SAS-MX alkaline gel electrophoresis kit as the reference method. RESULTS: The %HbA2 values from the Variant II analyzer and the HELENA SAS-MX alkaline gel electrophoresis kit show a good linear correlation in the absence of HbS. A strong positive bias in the %HbA2 values from the Variant II is apparent in the presence of HbS in the samples, when compared to the alkaline electrophoresis gel. CONCLUSION: The Variant II analyzer gives reliable results for %HbA2 determination when no HbS is detectable in the samples. When HbS is present, the gel electrophoresis method gives more accurate results.     

The silent hemoglobin alpha chain variant Hb Riccarton [alpha51(CE9)Gly-->Ser] may affect HbA1c determination on the HLC-723 G7 analyzer

BACKGROUND: Structural hemoglobin variants can affect the accuracy of hemoglobin A1c (HbA1c) testing and represent the most common pitfall in the determination of HbA1c. We here describe the characterization of an alpha chain variant in diabetic patients as the cause of an abnormal presentation of the HbA1c fraction on the HLC-723 G7 analyzer. METHODS: HbA1c analysis was performed using various HPLC-based HbA1c analyzers and by immunoassay. alpha-Globin mutation analysis was performed by GAP-PCR and DNA sequencing. RESULTS: The peak partially overlapping HbA1c in the chromatogram represents the glycated fraction of the silent alpha chain variant Hb Riccarton [alpha51(CE9)Gly-->Ser]. This aberrant peak is uniquely identified by the HLC-723 instrument, as it is not observed on other HPLC-based HbA1c analyzers. Occasionally, the HLC-723 may fail to properly integrate both glycated Hb fractions, resulting in a falsely low HbA1c result. The variant was confirmed in samples from other diabetic patients with identical chromatographic patterns. CONCLUSIONS: The silent alpha chain variant Hb Riccarton [alpha51(CE9)Gly-->Ser] leads to an abnormal chromatographic presentation on the HLC-723 analyzer with a risk of erroneous HbA1c determination. Manual validation of chromatograms to detect abnormalities caused by Hb variants is important to prevent incorrectly produced HbA1c results from being reported.     

HLC-723 G7糖化血红蛋白分析仪性能的评价及其在糖尿病筛查的应用

目的评价HLC-723 G7糖化血红蛋白分析仪的临床应用性能,并建立深圳地区健康人群糖化血红蛋白（HbA1c）的参考区间及用于糖尿病筛查的＂cut-off＂值。方法对HLC-723 G7测定HbA1c的精密度、准确度、线性、携带污染进行评价;并检测482例健康体检者和150例糖尿病患者HbA1c。结果HLC-723 G7测定HbA1c高、低两水平批内精密度的CV分别为0.69%、0.94%,总精密度的CV分别为1.25%、1.79%;HLC-723 G7与VARIANTⅡ测定HbA1c结果呈明显相关（r=0.996,Sy.x=0.28,P〈0.001）,在6.0%、7.0%、9.0%的相对偏倚分别为-0.40%-、0.14%、0.20%;HLC-723 G7测定HbA1c在3.1%-15.9%范围内线性良好（r=0.999,P〈0.001）,高值标本对低值标本的测定结果无明显携带污染;深圳地区健康人群HbA1c总体参考区间为4.5%-6.1%;HbA1c用于糖尿病筛查受试者工作（ROC）曲线下面积为0.934,＂cut-off＂值5.9%处灵敏度为82.0%,特异性为91.3%。结论HLC-723 G7糖化血红蛋白分析仪测定HbA1c性能良好,可用于糖尿病的早期筛查。     

Analytical evaluation of the Tosoh HLC-723 G8 automated HPLC analyzer for hemoglobin analysis in beta-thalassemia mode

ObjectivesThe analytical performances of a new kit conceived for Hb variants separation and measurement procedures on an HPLC instrument (Tosoh HLC-723 G8) were studied.ResultsBetween-run and within-run precision tests were satisfactory for both HbA2 and HbF measurements. HbA2 and HbF values measured using the TOSOH HLC-723 G8 were correlated to those obtained using the Bio-Rad Variant II HPLC system (r = 0.974 and 0.997 respectively) and to those given by the Sebia Capillary's system (r = 0.980 and 0.996 respectively). Linearity was observed for HbA2 from 2.24% to 6.56% and for HbF from 0.5 to 6%.ConclusionThe new analyzer Tosoh HLC-723 G8 was found to have a wide analytical range for both HbA2 and HbF. The G8 Mode beta-thal is suitable for a first-level laboratory screening for Hb analysis but also for a second-level test for the characterization of Hb variants after a first-line screening.     

Evaluation of the analytic performances of the new HPLC system HLC-723 G7 for the measurement of hemoglobin A1c

OBJECTIVES: The analytical performance of a new automated HPLC system, for the determination of HbA1C in blood (Tosoh HLC-723 G7), was studied. DESIGN AND METHODS: The study design included the evaluation of imprecision, linearity, interference and carryover. Comparison study was performed by comparing HbA1C results with those obtained from an established method (Bio-Rad Variant II). RESULTS: Total imprecision was less than 1.34% and the results were linear up to 17.2% HbA1C. The method showed a wide analytical range, and no carryover between specimens. Comparison study yielded, r=0.989, Sy.x=0.255, regression equation (y=0.9895x-0.35); Bland-Altman plot showed a mean bias=- 0.43% HbA1C with confidence limits ranging from -0.48% to -0.38% HbA1C. The presence of abnormal hemoglobin was clearly revealed, and no interference from labile HbA1C was apparent. CONCLUSION: The HLC-723 G7 instrument seems to be a reliable system for routine assay of HbA1C.     

Silent hemoglobin variants and determination of HbA(1c) with the high-resolution program of the HPLC HA-8160 hemoglobin analyzer

OBJECTIVES: Evaluation of HbA1c determination with an automated ion-exchange high-performance liquid chromatography (HPLC) method in patients with clinically silent hemoglobin (Hb) variants. DESIGN AND METHODS: HbA1c values were determined with the Arkray HA-8160 ion-exchange HPLC using the high-resolution, 4.2-min beta-thalassemia screening mode in patients with silent hemoglobin (Hb) variants, namely, Hb Graz, Hb Sherwood Forest, Hb O Padova, and HbD. RESULTS: All of these hemoglobin variants caused additional peaks in the chromatograms, without HbA1c results in patients with Hb Graz and Hb Sherwood Forest, and demonstrated extra peaks with HbA1c results that were clinically too low for patients with Hb O Padova and in the patient with HbD. CONCLUSIONS: The development of this automated HPLC method modification with high-resolution beta-thalassemia screening mode aids identification of interference due to some clinically silent Hb variants in HbA(1c) determination.     

Analytical evaluation of the Bio-Rad variant II automated HbA(1C) analyzer

OBJECTIVES: To evaluate the analytical performance of the Bio-Rad Variant II HbA(1C) analyzer (a completely automated system for the quantification of glycohemoglobin [HbA(1C)] in blood). DESIGN AND METHODS: The analytical parameters of precision, linearity and analytical range were assessed and HbA(1C) results from the Variant II were compared to HbA(1C) results from the Bio-Rad Variant (a method certified by the National Glycohemoglobin Standardization Program). The effect of a variety of hemoglobin variants on HbA(1C) obtained on the system was investigated. RESULTS: Total imprecision was less than 5% and the results compared well with those from an established method. The method has a wide analytical range with no carryover between specimens. CONCLUSION: The HbA(1C) method on the Variant II gives acceptable analytical performance.     

糖化血红蛋白不同测定方法的可比性研究

目的对离子交换高效液相色谱法(IE-HPLC)、硼酸盐亲和层析高效液相色谱法(AC-HPLC)和高效毛细管电泳法(HPCE)测定糖化血红蛋白(HbA1c)进行比对分析和偏倚评估,实现不同方法检测结果的可比性。方法以IE-HPLC法为参比方法(该法已通过美国NGSPⅠ级实验室认证),HPCE法和AC-HPLC法为实验方法,依据美国临床和实验室标准化协会(CLSI)EP9-A3文件进行方法学比对和偏倚评估,比对前进行参比方法正确度验证和实验方法精密度验证;对不可比的实验方法用经NGSP样本赋值传递的新鲜全血实施校准,校准后进行可比性的验证。结果参比方法对10个定值NGSP样本进行检测,检测结果全部在靶值的±6%内。两个实验方法的批内CV均1.5%,批间CV均2.0%。HPCE法在医学决定水平处与参比方法的偏倚分别为-0.06%和-0.07%,小于1/2 CAP TEa,与参比方法具有可比性;AC-HPLC法分别为-0.31%和-0.31%,均大于1/2 CAP TEa,与参比方法不可比;用经NGSP样本赋值传递的两个浓度新鲜全血校准AC-HPLC法,校准后的偏倚分别为0.08%和0.09%,均小于1/2 CAP TEa,与参比方法具有可比性。结论不同方法对HbA1c的测定结果可能存在差异,CLSI EP9-A3是评估这些差异的有效工具,用经NGSP样本赋值传递的新鲜全血对不可比的方法实施校准,可实现检验结果的可比性。     

Performance characteristics of beta-2-microglobulin measurements on a Beckman Immage analyzer with the DakoCytomation reagent kit

Objective

Evaluation of serum beta-2-microglobulin (β2M) in an automated analyzer.

Design and methods

The DakoCytomation β2M kit is an antibody based reagent intended for quantitative determination of β2M in serum and plasma by rate nephelometry.

Results

The limit of blank is 0.16 mg/L. The method is linear up to 17.9 mg/L. The imprecision ranged from 2.1% to 7.9% at the concentrations of 1.77 and 7.19 mg/L, respectively. Method comparison yielded slope = 1.009, r = 0.998. No interference was observed from hemolytic or icteric specimens. Reference interval of a healthy population was 1.13 mg/L to 3.04 mg/L.

Conclusion

The DakoCytomation reagent is acceptable to measure serum β2M.     

血红蛋白A2和F的室间质量评价结果分析

目的 评价中国部分珠蛋白生成障碍性贫血筛查实验室检测血红蛋白A2和F的水平和现状。方法 向50家珠蛋白生成障碍性贫血实验室发放两个批号的质控品,收集实验室回报的HbA2和HbF检测值,对回报的结果按照方法分组进行统计分析,并评价其检测水平。结果 49家实验室回报了检测结果,回报率为98%。HbA2的及格率为42.9%～92.3%,HbF的及格率为27.3%～84.6%。通过稳健Z比分数统计,血红蛋白HbA2项目201311批号样本有3家实验室检测结果为不满意,201312批号样本有4家实验室检测结果为不满意,血红蛋白HbF项目201311批号样本有5家实验室检测结果为不满意,201312批号样本有3家实验室检测结果为不满意。结论 我国珠蛋白生成障碍性贫血筛查实验室检测HbA2和HbF质量有待进一步提高。     

Evaluation of an affinity chromatographic procedure for the determination of glycosylated hemoglobin (HbA1)

An affinity chromatographic method for the determination of glycosylated hemoglobin (HbA1) was evaluated. The procedure was shown to be precise, the within- and between-assay coefficients of variation being less than 5%. It was also shown to correlate well with electrophoresis (r = 0.968) and ion-exchange chromatography (r = 0.916). An inverse relationship was shown to exist between increasing temperature and HbA1 levels measured by affinity chromatography. A statistically significant difference was found for samples run at 20 degrees C and 25 degrees C respectively, suggesting that the method should be run in a temperature-controlled environment. The affinity procedure was also shown not to be affected by the type of anticoagulant, the concentration of hemoglobin in the hemolysate, and acetylation.     

标本保存条件对Tosoh G7糖化血红蛋白分析仪测定结果稳定性的影响

目的探讨不同温度、不同贮存时间保存标本对Tosoh G7糖化血红蛋白分析仪测定糖化血红蛋白A1c(HbA1c)结果稳定性的影响。方法收集5例HbA1c水平不同的全血标本,用Tosoh G7糖化血红蛋白分析仪于当日3 h内测定结果,然后将各标本充分混匀后分装成4小管,分组贮存在室温(20~22℃)、冷藏(4~6℃)、冷冻(-18~-20℃)和低温冷冻(-74~-76℃)条件下,分别在贮存的第1、2、5、6、7、14、20、21、60和180天进行测定。以低温冷冻保存标本所测结果为标准,每个标本的HbA1c结果在低温冷冻组x珋±0.2%范围内为可接受结果。当每组5个标本的结果都在可接受范围内,说明标本在特定时间、特定温度下稳定。结果标本用Tosoh G7糖化血红蛋白分析仪测定的稳定性分别为:室温和-18~-20℃可稳定5 d,4~6℃可稳定20 d;-74~-76℃至少可稳定180 d。结论不同温度、不同贮存时间对Tosoh G7糖化血红蛋白分析仪测定HbA1c结果稳定性有影响。     

The determination of capillary blood glucose using the automatic clinical analyzer (aca) Dupont (author's transl)

The determination of capillary blood glucose after deproteinization using the aca is described. The method, which uses the hexokinase/glucose-6-phosphate dehydrogenase reaction, is compared with the glucose dehydrogenase method. The comparison shows that glucose values measured in capillary blood are essentially the same in both methods. The requirements for quality control are fulfilled. The method is not influenced by hemolysis, bilirubinemia, and hypertriglyceridemia.