d-Dimer Testing in Laboratory Practice

[摘要] BACKGROUND: d-dimer is a reliable and sensitive index of fibrin deposition and stabilization. As such, its presence in plasma should be indicative of thrombus formation. There are many conditions unrelated to thrombosis in which d-dimer concentrations are high, however, making its positive predictive value rather poor.CONTENT: Notwithstanding these limitations, d-dimer can be regarded as a most valuable laboratory tool to diagnose and manage a vast array of thrombosis-related clinical conditions, including ( a ) diagnosis of venous thromboembolism (VTE), ( b ) identification of individuals at increased risk of first thrombotic event (both arterial and venous), ( c ) identification of individuals at increased risk of recurrent VTE, ( d ) establishment of the optimal duration of secondary prophylaxis after a first episode of VTE, ( e ) pregnancy monitoring, and ( f ) diagnosis/monitoring of disseminated intravascular coagulation (DIC). This article is aimed at reviewing the merits and pitfalls of these applications.SUMMARY: From my analysis of the literature, I draw the following conclusions. ( a ) d-dimer, as measured by a sensitive test, can be safely used to exclude VTE in symptomatic outpatients, provided that it is used in combination with the pretest clinical probability. ( b ) High concentrations of d-dimer are associated with an increased risk of recurrent VTE. ( c ) Patients who present with d-dimer above cutoff after stopping the regular course of oral anticoagulation benefit from extended prophylaxis. ( d ) Finally, d-dimer can be used as a fibrin-related degradation marker for the diagnosis/management of patients with DIC.

[学科分类] 过敏症与临床免疫学