Monthly Newsletter

The Clinical and Laboratory Standards Institute (CLSI) has published an updated version of H52-A2—Red Blood Cell Diagnostic Testing Using Flow Cytometry; Approved Guideline—Second Edition.

This standard addresses the diagnostic red blood cell (RBC) assays performed as fluorescence-based assays on a flow cytometry platform; including testing procedures for fetomaternal hemorrhage detection, paroxysmal nocturnal hematuria screening, membrane defect anemia testing for hereditary spherocytosis, and nucleated RBC counting. Points of validation and quality control, and caveats of interpretation are also discussed.

This revised edition includes preferred testing methodology for diagnosis of paroxysmal nocturnal hemoglobinuria and nonimmune membrane-associated hemolytic anemias. H52-A2 examines diagnostic tools to further evaluate anemic conditions by the reliable quantitation of adult F-cells and nucleated RBCs. It discusses points of validation and quality control, and caveats of interpretation.

CLSI also published a new hematology document, H60-A—Laboratory Testing for the Lupus Anticoagulant; Approved Guideline. This standard provides guidance and recommendations regarding the proper collection and handling of the specimen; descriptions and limitations of screening and confirmatory assays, and mixing tests used to identify lupus anticoagulant (LA); determination of cutoff values and calculations associated with the various assays; and interpretation of test results in an LA panel.

This new standard assists in the standardization of LA testing and addresses preexamination issues, examination concerns, and postexamination matters that pertain to interpretation of individual tests or combinations of assays. It was written by experts in the field who reached a consensus on six criteria needed for making the laboratory diagnosis of LA. The document guides the reader on how the criteria can be met by offering practical information sourced from nearly 300 references. H60-A also includes seven appendixes to help visually aid the reader.

"I would recommend H60-A to laboratories who are either considering adding these assays to their testing menu or who are currently performing LA testing. These guidelines are the most comprehensive to date on this topic. H60-A thoroughly addresses LA test validation and pre- and postexamination issues, while giving the reader in-depth information on all tests used for screening and confirming for the presence of the antibody," highlighted Ms. Marlies Ledford-Kraemer, MBA, BS, MT(ASCP)SH, H60-A Document Development Committee Chairholder, and President, CLOT-ED, Inc.

H60-A is intended for laboratory personnel responsible for performing LA testing, physicians (eg, hematologists, pathologists, rheumatologists), external quality assessment programs, researchers, and manufacturers of reagents used in LA testing.

CLSI is a not-for-profit membership organization that brings together the varied perspectives and expertise of the worldwide laboratory community for the advancement of a common cause: to foster excellence in laboratory medicine by developing and implementing clinical laboratory standards and guidelines that help laboratories fulfill their responsibilities with efficiency, effectiveness, and global applicability.

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