[Analysis of D-dimer laboratory findings and clinical evaluation]

D-dimer is a product of the enzymatic degradation of the fibrinogen-fibrin molecule, and its existence is demonstrable in circulation. The test based limits may be considered as normal values. It was first thought to be a product of coagulation, then a product of lysis. High-concentration D-dimer in blood detected in thromboembolic diseases is considered to be of diagnostic value. In cases where thromboembolism was ruled out despite elevated titres but heparin (LMWH) or CLOPIDOGREL was given as a cautionary measure, we found that D-dimer values remained elevated. This finding means that in vivo coagulation is not a precondition to D-dimer formation. Analysis of such cases uncovers liver or kidney disease in the background, but old age may also be a factor. Often elevated ferritin levels were observed 'in parallel' with elevated D-dimer values. These findings lead us to presume an enzymatic degradation process of 'elderly' protein molecules, which is universally applicable. Orv Hetil. 2017; 158(50): 1971-1976.