{"title":"使用发色性自动测定法定量分析 C1 抑制剂活性:分析和临床表现。","authors":"Yves Renaudineau, Laurent Sailler, Bénédicte Puissant-Lubrano","doi":"10.1515/cclm-2024-0024","DOIUrl":null,"url":null,"abstract":"<p><strong>Objectives: </strong>The quantification of functional C1 inhibitor activity (fC1-INH) is an important tool to diagnose bradykinin-mediated angioedema (AE), whether hereditary or acquired. For that an accurate assay is necessary, therefore we evaluated the analytical performances of a fC1-INH chromogenic assay (Berichrom<sup>®</sup>, Siemens) performed utilizing an Optilite turbidimeter (Binding Site).</p><p><strong>Methods: </strong>fC1-INH was quantified by means of the chromogenic assay Berichrom<sup>®</sup>. Internal quality controls were used to determine the precision of the assay. Stability under various storage and matrix conditions, uncertainty, linearity, interference (of hemolysis, lipemia, and icterus), agreement with the manual Technochrom<sup>®</sup> assay, and diagnostic performances were further evaluated on samples from patients and healthy donors.</p><p><strong>Results: </strong>The fC1-INH Berichrom<sup>®</sup> assay presented good performances regarding intra- and inter-assay precision (CV: 1.3-4.5 % and 3.0-6.0 %, respectively), expanded uncertainty (5.5 % at normal level and 12.5 % at the clinical threshold) and linearity (rho<sup>2</sup>>0.99: range 7-130 % activity). Addition of interfering substances (hemoglobin <16 g/L, intralipid<sup>®</sup> <12 g/L, and bilirubin <1 g/L) did not affect fC1-INH quantification. fC1-INH activity from healthy donors remained stable in citrate whole blood until 4 days at room temperature, and 7 days when plasma was collected. Agreement between the automated Berichrom<sup>®</sup> assay and the manual Technochrom<sup>®</sup> assay (n=47) was excellent as obtained with both quantitative (Deming regression and Bland-Altman difference plot) and qualitative (Kappa index=1) analyses. Finally, the diagnostic performance of the quantification of fC1-INH for AE evaluated on 81 patients revealed a sensitivity of 100 %, a specificity of 97.2 %, a positive predictive value of 83.3 % and a negative predictive value of 100 %.</p><p><strong>Conclusions: </strong>The automated fC1-INH Berichrom<sup>®</sup> assay showed good performance, both at the analytical and diagnostic/clinical levels that allowed its usage in a clinical laboratory for C1-INH-dependent bradykinin-mediated AE research in combination with quantitative C1-INH and C4 determinations.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":null,"pages":null},"PeriodicalIF":3.8000,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Quantification of C1 inhibitor activity using a chromogenic automated assay: analytical and clinical performances.\",\"authors\":\"Yves Renaudineau, Laurent Sailler, Bénédicte Puissant-Lubrano\",\"doi\":\"10.1515/cclm-2024-0024\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Objectives: </strong>The quantification of functional C1 inhibitor activity (fC1-INH) is an important tool to diagnose bradykinin-mediated angioedema (AE), whether hereditary or acquired. For that an accurate assay is necessary, therefore we evaluated the analytical performances of a fC1-INH chromogenic assay (Berichrom<sup>®</sup>, Siemens) performed utilizing an Optilite turbidimeter (Binding Site).</p><p><strong>Methods: </strong>fC1-INH was quantified by means of the chromogenic assay Berichrom<sup>®</sup>. Internal quality controls were used to determine the precision of the assay. Stability under various storage and matrix conditions, uncertainty, linearity, interference (of hemolysis, lipemia, and icterus), agreement with the manual Technochrom<sup>®</sup> assay, and diagnostic performances were further evaluated on samples from patients and healthy donors.</p><p><strong>Results: </strong>The fC1-INH Berichrom<sup>®</sup> assay presented good performances regarding intra- and inter-assay precision (CV: 1.3-4.5 % and 3.0-6.0 %, respectively), expanded uncertainty (5.5 % at normal level and 12.5 % at the clinical threshold) and linearity (rho<sup>2</sup>>0.99: range 7-130 % activity). Addition of interfering substances (hemoglobin <16 g/L, intralipid<sup>®</sup> <12 g/L, and bilirubin <1 g/L) did not affect fC1-INH quantification. fC1-INH activity from healthy donors remained stable in citrate whole blood until 4 days at room temperature, and 7 days when plasma was collected. Agreement between the automated Berichrom<sup>®</sup> assay and the manual Technochrom<sup>®</sup> assay (n=47) was excellent as obtained with both quantitative (Deming regression and Bland-Altman difference plot) and qualitative (Kappa index=1) analyses. Finally, the diagnostic performance of the quantification of fC1-INH for AE evaluated on 81 patients revealed a sensitivity of 100 %, a specificity of 97.2 %, a positive predictive value of 83.3 % and a negative predictive value of 100 %.</p><p><strong>Conclusions: </strong>The automated fC1-INH Berichrom<sup>®</sup> assay showed good performance, both at the analytical and diagnostic/clinical levels that allowed its usage in a clinical laboratory for C1-INH-dependent bradykinin-mediated AE research in combination with quantitative C1-INH and C4 determinations.</p>\",\"PeriodicalId\":10390,\"journal\":{\"name\":\"Clinical chemistry and laboratory medicine\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.8000,\"publicationDate\":\"2024-06-12\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Clinical chemistry and laboratory medicine\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1515/cclm-2024-0024\",\"RegionNum\":2,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MEDICAL LABORATORY TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinical chemistry and laboratory medicine","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1515/cclm-2024-0024","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MEDICAL LABORATORY TECHNOLOGY","Score":null,"Total":0}
Quantification of C1 inhibitor activity using a chromogenic automated assay: analytical and clinical performances.
Objectives: The quantification of functional C1 inhibitor activity (fC1-INH) is an important tool to diagnose bradykinin-mediated angioedema (AE), whether hereditary or acquired. For that an accurate assay is necessary, therefore we evaluated the analytical performances of a fC1-INH chromogenic assay (Berichrom®, Siemens) performed utilizing an Optilite turbidimeter (Binding Site).
Methods: fC1-INH was quantified by means of the chromogenic assay Berichrom®. Internal quality controls were used to determine the precision of the assay. Stability under various storage and matrix conditions, uncertainty, linearity, interference (of hemolysis, lipemia, and icterus), agreement with the manual Technochrom® assay, and diagnostic performances were further evaluated on samples from patients and healthy donors.
Results: The fC1-INH Berichrom® assay presented good performances regarding intra- and inter-assay precision (CV: 1.3-4.5 % and 3.0-6.0 %, respectively), expanded uncertainty (5.5 % at normal level and 12.5 % at the clinical threshold) and linearity (rho2>0.99: range 7-130 % activity). Addition of interfering substances (hemoglobin <16 g/L, intralipid® <12 g/L, and bilirubin <1 g/L) did not affect fC1-INH quantification. fC1-INH activity from healthy donors remained stable in citrate whole blood until 4 days at room temperature, and 7 days when plasma was collected. Agreement between the automated Berichrom® assay and the manual Technochrom® assay (n=47) was excellent as obtained with both quantitative (Deming regression and Bland-Altman difference plot) and qualitative (Kappa index=1) analyses. Finally, the diagnostic performance of the quantification of fC1-INH for AE evaluated on 81 patients revealed a sensitivity of 100 %, a specificity of 97.2 %, a positive predictive value of 83.3 % and a negative predictive value of 100 %.
Conclusions: The automated fC1-INH Berichrom® assay showed good performance, both at the analytical and diagnostic/clinical levels that allowed its usage in a clinical laboratory for C1-INH-dependent bradykinin-mediated AE research in combination with quantitative C1-INH and C4 determinations.
期刊介绍:
Clinical Chemistry and Laboratory Medicine (CCLM) publishes articles on novel teaching and training methods applicable to laboratory medicine. CCLM welcomes contributions on the progress in fundamental and applied research and cutting-edge clinical laboratory medicine. It is one of the leading journals in the field, with an impact factor over 3. CCLM is issued monthly, and it is published in print and electronically.
CCLM is the official journal of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) and publishes regularly EFLM recommendations and news. CCLM is the official journal of the National Societies from Austria (ÖGLMKC); Belgium (RBSLM); Germany (DGKL); Hungary (MLDT); Ireland (ACBI); Italy (SIBioC); Portugal (SPML); and Slovenia (SZKK); and it is affiliated to AACB (Australia) and SFBC (France).
Topics:
- clinical biochemistry
- clinical genomics and molecular biology
- clinical haematology and coagulation
- clinical immunology and autoimmunity
- clinical microbiology
- drug monitoring and analysis
- evaluation of diagnostic biomarkers
- disease-oriented topics (cardiovascular disease, cancer diagnostics, diabetes)
- new reagents, instrumentation and technologies
- new methodologies
- reference materials and methods
- reference values and decision limits
- quality and safety in laboratory medicine
- translational laboratory medicine
- clinical metrology
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