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Coagulation Factor Characteristics

Two coagulation factor questions from Madan Verma, MLT: I was cruising through your website and I have two questions: Do coagulation factors circulate in blood as activated proteins or they are in a non-active form? Is there a certain proportion of activated and non-active? Factor VII (activated or native form?) has the shortest half life […]

Sekusui Chemical Plans to Acquire ADI

Steve Duff of Precision BioLogic alerted me to this March 18, 2009 news releasefrom American Diagnostica, Inc and Sekusui Chemical Company, Ltd describing Sekusui plans to acquire 100% of ADI. This is a big change for a company with a long US in vitro diagnostics history.

VWF Cleavage Regulation by Shear Force and ADAMTS13

Steve Duff of Precision BioLogic forwarded a reference to a mechanical and enzymatic mechanism that controls the length of von Willebrand factor (VWF) multimers. According to Zhang X, Halvorsen K, Zhang CZ, Wong WP, Springer TA: Mechanoenzymatic cleavage of the ultralarge vascular protein von Willebrand factor. Science 2009;324:1330-4, shear force exerted on the VWF molecule “unrolls” the molecule […]

Leukocyte Adhesion Deficiency and Platelets

An interesting question from Stephanie Morgan, MT (ASCP) Chief Technologist at the Children’s Cancer Clinic, University of Mississippi Medical Center, Jackson, Mississippi. Her question was originally sent to Bernadette (Bunny) Rodak at Indiana University Medical Center. Bunny forwarded it to me to post here. Bunny, I have been asked to aggregate a two-year old with […]

Monitoring Clopidogrel

Karen Lusky, staff writer for CAP Today, provides an excellent summary of the potential need for monitoring clopidogrel (Plavix) antiplatelet therapy in “Getting personal about antiplatelet therapy” in the May 2009 issue. She discusses polymorphisms of the CYP2C19 metabolic pathway and their effect upon clopidogrel dosage and efficacy. She also discusses phenotypic assays for antiplatelet […]

Congreso Cientifico, Honduras, July 1-3

Margaret Fritsma, MA, MT (ASCP) SBB and I will participate in the Congreso Cientifico, at the Intercontinental Hotel Tegucigalpa, Honduras at the invitation of Milena Vanegas, MS MT (ASCP) on Wednesday, July 1 through Friday, July 3, 2009. We thank Ms. Vanegas for the invitation and look forward to presenting at the meeting. Here is […]

ISTH XXII Congress Boston July 11-16, 2009

The International Society on Thrombosis and Haemostasis XXII Congress is planned for July 11-16 at the convention center in Boston, MA. This biennial meeting is the biggest international hemostasis event. Geo

Failing to Mix Coagulation Specimens

A participant in Medlab-L has witnessed phlebotomists who do not mix the blue top tubes for coagulation testing as they are drawn. They draw and label the tubes, laying them down as they are collected without mixing. Though not for coagulation testing, I have had the same experience when having blood collected for a CBC […]

Discontinue Plavix Before Assay?

Last week we posted a follow-up question about specimen collection for Plavix efficacy testing. The question was, “How long should patients go without Plavix before aggregometry testing?” The answers were: a. 48 hours: 2 (18%) b. 7 days: 5 (45%) c. 10 days: 3 (27%) d. 14 days: 1 (9%) Only eleven of us responded, which […]

Autoanti-FVIII and the Bethesda Titer

From Kim Kinney. (Clarian gets the most interesting cases.) Hi George. We have a patient with an acquired factor VIII (FVIII) inhibitor. He started out having <1% VIII, but he is now up to 33%. He has had a Bethesda titer all along, but it is starting to go down. One thing I noticed is […]

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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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