Bleeding Disorders

When Do We Titer Inhibitors?

Dana Carton asks, “We currently test for factor inhibitors using the clot-based Bethesda titer as well as a chromogenic bovine assay for Hemlibra patients no matter what the factor level. We recently learned that colleagues don’t look for that inhibitor unless the factor level is less than 5%. Is this a common practice, and would […]

Video: Have We Cured Hemophilia?

Click here to view my (Geo) video, Have We Cured Hemophilia?, recorded with Professors Malissa Norfolk and David Cabral as part of their series, Differential Discussions. Part One reviews the history of hemophilia management from the time the first antihemophilic factor was produced to 2014 when turned to the extended half-life hemophilia concentrates.

Bleeding Disorders

Updated DIC Parameters from ISTH

The ISTH SSC Subcommittee on Disseminated Intravascular Coagulation has published its latest definition and scoring system for DIC. Click below for the open-access article. Iba T, Levy JH, Maier CL, et al. Updated definition and scoring of disseminated intravascular coagulation in 2025: communication from the ISTH SSC Subcommittee on Disseminated Intravascular Coagulation. J Thromb Haemost. […]

Bleeding Disorders

Agent Orange

This entry was in response to a question from Dennis Brondi: “Hi–I was exposed to Agent Orange and have primary APS (also single parent factor V Leiden). Do you know of any studies establishing causation between AO and APS? My issues have included avascular necrosis of both femoral heads and multiple large DVTs from the […]

Bleeding Disorders

Bovine Chromogenic FVIII Recovery

Click here to read a poster presented at ISLH: Quinton T, Black KM, Sadeghi-Khomami A. Performance of a Novel Bovine Chromogenic Factor VIII Assay in the Recovery of Factor VIII Replacement Therapies. ISLH 2025. The investigators report the efficacy of a chromogenic substrate FVIII assay that employs bovine reagents on several FVIII therapeutics in current use.

Plasma Collection for IVD

Thanks to Mr. Darcy Shannon of Drumlin Plasma, Inc. for the attached SOP, which distinguishes between plasma collected for IVD applications, such as coagulation calibrators, controls, and reagents, and plasma collected to produce therapeutic plasma fractions.

Bleeding Disorders

FVIII-Depleted Reagent Plasma With and Without VWF

The poster, Henneberry S, Rahman M,Wood A, Notini KM, Black KM, Sadeghi-Khomami A. Comparative analysis of commercial factor VIII (FVIII) deficient plasmas with and without von Willebrand factor for FVIII one-stage clotting assay (OSA) was presented on Thursday, 8 May 2025 at the ISLH meeting in Halifax, NS. Click here to see the poster.

Bleeding Disorders

Global Organizations Issue Urgent Call to Action

Click here for the ISTH 6 May 2025 Call to Action: Critical Juncture in Hemophilia Treatment. Thanks to Elaine Benoit, Precision BioLogic Inc. for the heads-up. Please post your comments below. From Bob Gosselin, 7 May 2025: This link is more of a political statement than any notion of gene Rx acceptance treatment in HA […]

Bleeding Disorders

The Choice of Hemophilia Treatments

Here is a brief and informative editorial that lists current hemophilia Rx choices: Makris M, O’Mahony B. Hemophilia treatments and the paradox of choice. Res Pract Thromb Haemost. 2025;9:102726. doi: 10.1016/j.rpth.2025.102726. PMID: 40224276; PMCID: PMC11992418.

Bleeding Disorders

Antithrombin Assay Supports Fitusiran Therapy

Here’s a link to our 1 April 2025 Sanofi announcement about the FDA approval of Fitusiran® therapy. Sanofi provides the Siemens Healthineers’ INNOVANCE Antithrombin® assay, a chromogenic substrate method, as a companion diagnostic tool to support Fitusiran dosing. A Sanofi-supported study compared eight antithrombin activity assay kits on seven coagulometers to indicate the reagent-instrument combinations […]

Bleeding Disorders

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George Fritsma is a medical laboratory scientist, educator, and author. George holds faculty appointments with Rutgers University and Michigan State University, and is a member of the International Society on Thrombosis and Hemostasis, American Association of Clinical Chemists, and American Society for Clinical Laboratory Science.

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