Platelet Function Testing

Platelet Function Testing and the Bleeding Time

In 2009 Dave McGlasson and I published McGlasson DL, Fritsma GA, Whole blood platelet aggregometry and platelet function testing. Semin Thromb Hemost 2009;35:168–80. This article, the second-most cited in the 2009 Seminars in Thrombosis and Hemostasis, reminded me of our Quick Question about the Ivy bleeding time posted in early November, and subsequently lost when our site crashed […]

Bleeding Disorders

VerifyNow P2Y12 Assay: Change to PRU

I received this truncated communication on July 16 from Michael Suter with no follow-up, but I post it regardless, as Accumetrics’ decision to change their P2Y12 cartridge report seems to be a concern for many: “We monitor Plavix therapy using the VerifyNow P2Y12 assay kit. Accumetrics is in the process of discontinuing the reporting of percent inhibition, leaving the PRU […]

Antiplatelet Therapy

More on Aggregometer Validation

A big thank-you to Kathy Jacobs of Chrono-Log Corporation for her update on validation of aggregometry, added as a comment to

Platelet Function Testing

How to Validate an Aggregometer

From Rrosales: I am interested in purchasing a platelet aggregometer for our hematology lab, but we don’t have an existing instrument to compare it with. Some suggested H58 NCCLS (CLSI, does not really help) but I am used to validating an instrument with an old instrument (comparison/parallel testing). Can you tell me how to start the […]

Platelet Function Testing

Platelet Clumping in Sodium Citrate: Reprise

From Kathy Jacobs at Chronolog, Inc. Hi George, When a patient’s platelets clump in sodium citrate, is there another anticoagulant that can be used to allow LTA platelet aggregation testing? Thanx in advance, Kathy. Hi, Kathy, good to “hear” from you. You posted your question originally as a comment to a

Platelet Function Testing

Ristocetin: False Positives?

From Laurel Veek at Mayo Labs: We have noticed lately when performing platelet aggregations that more often than not we have a curve that is slow to develop but between 2-3 minutes it aggregates or has an abnormal slope if it aggregates before 3 minutes. Ideally I would like the curve to be relatively flat at […]

Platelet Function Testing

Undiagnosed Thrombocytopenia

From an anonymous inquirer: I have been misdiagnosed for years. I have very large and oval-shaped platelets which my average count is 40,000. I also tell whoever is taking my complete blood count (CBC) to make sure it is a manual count because my platelets are too large for the machine. I have great coagulation […]

Bleeding Disorders

Freeze-thaw Platelets and Growth Factors

From “abi:” We freeze-thaw platelets and aliquot them in 50 mL tubes stored at –80°C. After this we process 2–3 rounds of freeze thaw cycles before using these platelets in MSC cultures. 1. My question is, can we process this 2–3 rounds of freeze thaw cycle in advance, say a month prior to use, for […]

Platelet Function Testing

Serotonin Release by Immunoassay?

Dear George, For heparin-induced thrombocytopenia (HIT) serotonin release assay, can serotonin ELISA sensitive to HIT be used? With regards, Vilas Hiremath. Hello, Vilas, always good to hear from you. I had to go to experts, Drs Larry Brace, Edward Hospital in Naperville IL, and Jon Geske, Precision BioLogic Manager of Emerging Technologies & Markets. Here is a reply […]

Anticoagulant Therapy

PRP Gel, Platelet Substitute

Another interesting discussion from our UMDNJ graduate Hemostasis course: About 6 years back, I caught wind of a discussion regarding platelet substitutes, which I found quite intriguing. I did some digging as a result of this discussion and am amazed by the potential of such technologies. It appears that platelet rich plasma (PRP) gel has been around […]

Bleeding Disorders

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George Fritsma is a medical laboratory scientist, educator, and author. George is a member of the International Society on Thrombosis and Hemostasis, the International Society for Laboratory Hematology, and the American Society for Clinical Laboratory Science.

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