Mike Meyer asks, "we run three dilutions for all of our factor testing. Occasionally, we see results in which upon higher dilutions, the factor value decreases after adjusting for the dilution. For instance, I had a case today in which the FIX values were 0.64, 0.55, and 0.43 U/mL for the 1:10, 1:20, and 1:40 dilutions [values corrected for the dilution effect], the opposite effect seen with inhibitors. Calibration curve seems fine." He adds, "the patient’s FVIII level was very high [about 3.60 U/mL]. We possibly thought that the higher dilutions would bring the FVIII level back closer to a more normal range. The high concentration of FVIII in the first dilution may be accelerating the PTT clotting time yielding a falsely higher FIX value. Please comment."
Oct 23, 2020 12:44pm
Oct 20, 2020 5:24pm
Thanks to hemostasis expert and colleague Dave McGlasson for a recent phone discussion on the effects of marijuana on warfarin therapy [disclaimer: no
Oct 15, 2020 1:09pm
Announcing a 9-30-20 open access publication [forgive the self-reference]: McGlasson DL, Fritsma, GA. In vitro detection and removal of direct oral anticoagulants from patient plasma specimens. Annals of Blood 2020:doi: 10.21037/aob-20-16.