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."
Posts - Instrumentation
Oct 23, 2020 12:44pm
Nov 10, 2018 6:26am
Thanks to Ali Sadeghi-Khomami PhD, Precision BioLogic, and Joan Polancic, MS MLS, Denver Health, for the heads-up on this announcemment:
Nov 13, 2015 7:18am
George received this question from the ASCLS Consumer Web Forum via Bonnie Jo Taylor, MHS, MT(ASCP)SH.