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Greater New Orleans Conference

Coming up in just two weeks is the Greater New Orleans Coagulation Conference, February 9–10, 2012 at the New Orleans Marriott in Metarie, LA. Precision BioLogic, Inc will be exhibiting at the conference, and we look forward to seeing you there. Also, please visit our recently updated list of 2012 Coagulation Conferences. If you know of a […]

High D-dimer, low Fibrin Monomer in Amyloidosis

From “rhe25“: Hi, George, glad to find your resourceful website! Question for you: when the D-dimer is very very high, but the soluble fibrin monomer complex (SFMC) is negative, does that mean primary fibrinolysis in a systemic amyloidosis patient who has bleeding? I have seen a case like this, but the fibrinogen level is elevated, […]

Ristocetin Cofactor

Laura Lum, Seattle Children’s Hospital, asks, What is the ristocetin cofactor assay for, how is it performed, and can it be done on an STA Compact? Hi, Laura, the ristocetin cofactor assay is a test for von Willebrand factor (VWF) activity. Low VWF is the cause of von Willebrand disease (VWD). The assay began as platelet aggregometry […]

Bleeding Disorders

Faulty In Vitro Clotting in Myeloma

From Heidi Lawson: I was wondering if you had any information on why multiple myeloma (MM) patient specimens do not (at times or at all) spin down well in serum separator tubes (SST) or red top tubes. I called BD and they gave me a small excerpt of information stating that MM patients, due to myeloma […]

Specimen Management

Calculation Error in Lupus Anticoagulant Module #8

From Laura Lum at Seattle Children’s Hospital: I couldn’t follow the mathematical calculation for the 4:1 mix mentioned in the Lupus Anticoagulant presentation. The normal plasma is assumed 100%; the patient was 20%. The calculation was [100 + (20 x 4)] divided by 5. The answer was given as 32 but by my calculation, it should be 36 (180/5 […]

Collecting Blood from Hemodialysis Patient

This practical question was sent to the ASCLS Consumer Web Forum over the weekend: Where would you draw blood from a hemodialysis patient to obtain an ACT? I was always taught to draw from venous port to ascertain the ACT in the system to prevent clotting and blood loss. Thank you for your question. As […]

Specimen Management

Quick Question: Heparin Therapeutic Range

On October 21 I posted my

Anticoagulant Therapy

Clot-based Protein S Dilutions

From Lisa Reid-Fifoot, Technical Service Manager at Precision BioLogic: I am acquainted with an institution that performs several dilutions on the patient’s sample (1/5, 1/10, 1/20, 1/40, 1/80, 1/160) when performing the clottable protein S (PS) assay. They find they are not getting good agreement amongst all the dilutions especially with low results. I have not […]

New Ristocetin Lot and Storage Requirements

We’ve had two questions about Ristocetin since our 11.9.11 Problems with Ristocetin question from Kerri Klemm. Kerri’s question prompted me to contact Kathy Jacobs at Chrono-log Corp, a major distributor of ristocetin in the US and around the world. Here is a follow-up message from Kathy: Hello George, Nice to hear from you and a very happy New Year to you and your family. As […]

Bleeding Disorders

CAP Requires INR Reference Interval

From Dr. John Olson, University of Texas Medical Center in San Antonio: Hello George, Happy New Year! I hope that your holiday was as pleasant for you as mine was for me. I read with interest the brief piece on the reference interval for the INR. When I was at the University of Iowa a number of […]

Anticoagulant Therapy

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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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