Coagulation laboratories have a variety of choices for reagents. What are the differences and why are they important? Fresh frozen reagents are collected from the donor and frozen immediately. After thawing, they require no preparation, thaw and go. Lyophilization is the process of freeze drying a reagent to remove the liquid component. The process leaves …Continue Reading
Using Factor VIII Deficient Plasma from a human donor with a congenital deficiency is preferred to using an artificial immunodepleted Factor VIII substrate. There are several aspects that make congenital factor deficient plasma preferable to immunodepleted. The immunodepletion process During the immunodepletion process, not only is the Factor VIII removed, but the vonWillebrand factor is …Continue Reading
Laboratories use normal reference ranges (NRRs) to identify whether a test result is within the normal range or outside this range (and to thus identify an abnormal result). The relative false positive to true positive rate increases substantially for rare disorders and is a particular problem with congenital disorders such as protein C, protein S, …Continue Reading
A physician may order mixing studies when a patient’s prothrombin time (PT), activated partial thromboplastin time, (aPTT) or both PT and aPTT are prolonged outside the upper limit of the laboratory’s established normal range. Determining the cause of the prolongation It is important to determine if the cause of the prolongation is due to a …Continue Reading
