Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 447
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size
Year : 2020  |  Volume : 63  |  Issue : 2  |  Page : 255-257

Utility of grey zone testing strategy in transfusion transmissible infection testing in blood bank is of limited value!

Department of Transfusion Medicine, Medanta-The Medicity, Secor-38, Gurugram, Haryana, India

Correspondence Address:
Aseem K Tiwari
Department of Transfusion Medicine, Medanta-The Medicity, Sector-38, Gurugram - 122 001, Haryana
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/IJPM.IJPM_404_19

Rights and Permissions

Several blood banks use grey zone (GZ) phenomenon (defined as samples with optical density within 10% below the cut off in enzyme immuno-assay [EIA]/chemiluminescence immunoassay [CLIA]) to further augment blood safety. There is paucity of data regarding usefulness of GZ sample and its application in Transfusion Transmissible Infection (TTI) screening procedures in blood transfusion services. We looked at our GZ sample results and their confirmatory test results to verify if it adds to blood safety in our set-up? We performed a prospective analytical study on blood donors' samples over two years. All the donors' samples were screened for TTI using CLIA. Samples with signal/cut-off ratio between ≥0.90 and <1.00 were classified under GZ. They were re-tested in duplicate and submitted to confirmatory testing: Neutralization Test for HBsAg, Immunoblot for HCV, and Western blot for HIV. Among the 50,064 blood donors donating the blood during study period, 573 (1.14%) donors were reactive for HBsAg, HCV, and HIV. Forty-seven (0.1%) TTI samples were GZ, but none was “confirmed positive.” The utility of GZ testing seems to be limited. However, this may be continued for sake of “erring on the side of caution” and since this only results in negligible wastage (0.1%) of blood units.

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
    PDF Downloaded97    
    Comments [Add]    

Recommend this journal