Sep 18 2014
From Tony Tang, Clinical Laboratory of Tongji Hospital, Wuhan, China:
Hello George, recently we’ve met two or three cases from paediatrics with unexplained massively elevated D-dimer. In these cases, PT and PTT were normal, levels of fibrinogen were decreased (about 1.0-1.5g/L), different D-dimer reagents (STAGO AND IL) got consistent results, levels of rheumatoid factors were normal, clot and hemolysis of specimens could be excluded, however the second specimen from the same patient often got a normal D-dimer result on the next day. Did they got a transient hyperfibrinolysis? or we could attribute these to abnormal sampling for children? Thanks for your suggestion.
Hello, Tony, and thank you for your question. I can think of no clinical circumstance in which the D-dimer could fluctuate from massively elevated to normal within the same day, and based on the other lab results you report, may consider a sampling error or interference by some form of therapy. It would be interesting, however, to learn of the patients’ age and clinical condition for these cases. Do any of our participants have any experience of such wide D-dimer fluctuations?
Thank you all, I agree that these elevated D-dimer results m
Thank you all, I agree that these elevated D-dimer results most likely were due to microclot and subsequently ex vivo fibrinolysis, although a small clot is hard to be observed by naked eye.
There was a case report published in 1996 about falsely elev
There was a case report published in 1996 about falsely elevated D-dimer in infant with elevated thrombin time and reduced fibrinogen. Manual inspection of specimen did not reveal a macro clot but continuous rising of the D-dimer level in a stored specimen suggested an artificial result and only after closer examination of cell sediment a microclot <1 mm was detected: Carroll PA, Ray MJ. Erroneous D-dimer result on a paediatric citrated specimen. Blood Coagul Fibrinolysis 1996;7:502.