Bleeding Disorders

More on Promacta

From my friend Ali Sadeghi-Khomami, PhD, Precision Biologic Inc: Eltrombopag is a diazo derived compound that acts like pH indicators, i. e., it changes colour at different concentrations of hydronium ions. Thus it is expected that it interferes with chromogenic assays such as the bilirubin assay, especially when assay calibration will not match the colour of the testing sample. […]

Bleeding Disorders

Promacta and Brown Plasma

From John Mitsios, MD at Cornell. Hi George! I had a question regarding the effects of eltrombopag (Promacta®, a TPO stimulating agent), which is typically given to patients with immune thrombocytopenic purpura (ITP), on routine coagulation assays. The reason for this question is that it has been observed in some patients that at high doses the plasma […]

Bleeding Disorders

Ristocetin Cofactor Assay

From Kelly Townsend: Is anyone using the BioData PAP-8e for ristocetin cofactor (RICO) testing? We’ve moved from the old PAP-4 to the newer version, but are struggling with the assay. We’d appreciate being able to correspond with anyone who is sucessfully running RICO on the PAP-8e.

Bleeding Disorders

What is PF3?

Each year George enjoys the opportunity to teach in Dr. Elaine Keohane’s graduate course, CLSC 5124, Advanced Hemostasis at Rutgers University School of Health Related Professions. Our students are experienced medical laboratory scientists from all over the world, and they bring a wealth of practical knowledge. Dr. Keohane is teaching a section on platelet physiology this week, and […]

Bleeding Disorders

In Vivo Hemolysis

Irene Regan writes that despite doing major literature searches there seems to be no consensus regarding what coagulation results should be released when there is a suspicion of in vivo hemolysis such as in disseminated intravascular coagulation (DIC), when the samples are grossly haemolysed. Currently, Irene issues a fibrinogen (Clauss) and in this case she generally […]

Bleeding Disorders

Factor XIII Concentrate

In February 2011, the plasma-derived CLS Behring factor XIII concentrate Corifact™received US Food and Drug Administration (FDA) clearance to provide bleeding prophylaxis for patients with rare congenital factor XIII (fibrin stabilizing factor) deficiency. In January, 2013, the FDA extended Corifact’s indication to include management of perioperative bleeding in factor XIII-deficient patients. The Corifact package insert is attached here: Corifact Prescribing […]

Bleeding Disorders

Factor VIII Inhibitor?

From Deborah Whetzel, Children’s Hospital of the King’s Daughters, Norfolk, VA: We’ve had a couple patients lately that demonstrated inhibition but their factor VIII results are within normal limits or even elevated. The result values differ 30–40% typically between dilutions but as they’re diluted more, the values go up to 300 or 400%. FVIII values that high […]

Bleeding Disorders

Prolonged PT and PTT

A message from Vilas Hiremath: Dear George, hello. Female 30 yrs underwent laparoscopy, started bleeding. Prothrombin time (PT) and partial thromboplastin time (APTT, PT) prolonged, both mixing study 1:1 corrected. Normal fibrinogen and thrombin time (TT). Factor X, VIII. II normal, factor V is 6.0%. Dilute Russell viper venom time (DRVVT) screen and confirm both prolonged, […]

Bleeding Disorders

Prolonged PT, TT, and PTT

From Ning Tang: Hi, George, I come from a clinical laboratory in China. We met a confusing case today and want to get your suggestion: A patient had a prolonged prothrombin time (PT, 20s), partial thromboplastin time (APTT, PTT, 52s) and thrombin time (TT, 127s). Fibrinogen activity is within reference interval (by both Clauss method and […]

Bleeding Disorders

WFH Research RFP

The Word Federation of Hemophilia has just issued a research request for proposals. This is short notice, however, if you have a proposal, WFH will accept a letter of intent by August 31, 2013. Click WFH RFP for submission details.

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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