From Joanna Carroll, MT (ASCP), North Carolina State University College of Veterinary Medicine. We are running automated D-dimers and recently got a result of 0.00 ng/mL. Have you seen a value reported this low? Would it be better to report out the number as less than our lower limit of the reference range? Thanks for your help.
Hello, Joanna, no, I’ve never seen a D-dimer value of 0.0 ng/mL; were you testing a human or an animal? I have no experience with animal D-dimer values! I agree with you, I would report as less than the lower limit, particularly as a result this low would have no clinical significance unless you have identified some kind of interference. Please contact me if you have any follow-up.
Added 12.7.12: Joanna, I talked with Dave McGlasson, who has worked with a number of animal specimens, and he says the monoclonal antibodies in the quantitative D-dimer kits are specific for humans and do not detect animal D-dimers. Consequently, I assume that since your volume is high enough to run automated D-dimers, you must be testing humans. Nevertheless, I’ve not seen a 0.0 mg/mL D-dimer and would still suggest you just report as less than your lower limit. Geo.