LGCmain
Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 460
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size
ORIGINAL ARTICLE
Year : 2021  |  Volume : 64  |  Issue : 1  |  Page : 123-127

Comparative analysis of chromogenic vs clot.based one stage APTT assay for determination of factor VIII level


Department of Anatomy, Faculty of Medicine, Lincoln University College, Malaysia

Correspondence Address:
Mirza Asif Baig
Lincoln University College, Selangor
Malaysia
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/IJPM.IJPM_900_19

Rights and Permissions

Background: In the laboratory, factor VIII can be measured by three different methodologies, such as one-stage clotting assay, two-stage clotting assay, and chromogenic assay. These assays differ in ease of use, variety of reagents available, sensitivity to mild hemophilia A, and interference from lupus anticoagulants (LACs). Certain factor VIII gene mutations can cause discrepancy in results between one-stage activated partial thromboplastin time (APTT) and chromogenic assays. Materials and Methods: The coagulometer for factor VIII assay is Sysmex CS-5100. All data were expressed as mean ± standard deviation (SD). Results: A total of 135 cases were studied. Of these, 100 cases were of mild hemophilia A diagnosed by molecular genetics and, 15 cases were positive for LAC, which were confirmed by dilute Russell Viper venom test. Clot-based one-stage APTT assay showed 65% sensitivity and 80% specificity in diagnosing mild hemophilia A cases and out of 15 LAC cases, it showed false positivity in five cases. Chromogenic assay showed 85% sensitivity and 90% specificity in diagnosing mild hemophilia cases and was 100% specific in excluding LAC cases. Conclusions: One-stage APTT assay is the most commonly used test for determining factor VIII levels but chromogenic assay are considered as the gold standard and recommended as the reference method by European Pharmacopoeia and ISTH subcommittee. Mild hemophilia A patients with missense mutations show discrepancy between the one-stage clot-based APTT assay and chromogenic assays for determination of factor VIII level and this can lead to misdiagnosis or misclassification of mild hemophilia A. Therefore, it is recommended that both the assays should be used in the evaluation of mild hemophilia cases.


[FULL TEXT] [PDF]*
Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)
 

 Article Access Statistics
    Viewed186    
    Printed12    
    Emailed0    
    PDF Downloaded6    
    Comments [Add]    

Recommend this journal