How to Assay Factor II

Dear George, Thank you for the terrific, practical newsletter. It is a wonderful aid to those of us in clinical lab medicine.
Question from the below newsletter: In the case from “nomorefede”, is the factor II level measured in-house? If so, what method is used? Thanks!
Margie Peters, MD, Pathologist
Methodist Hospital, San Antonio, TX

Hi, Dr. Peters, I’m posting this so “nomorefede” is able to respond. Meanwhile I’m going to assume they are using a prothrombin time-based clot method using a factor II (prothrombin)-depleted reagent plasma. Factor II may alternatively be measured using the partial thromboplastin time (PTT), or a chromogenic assay.