Never ignore extremely elevated D-dimer levels: they are specific for serious illness

Neth J Med. 2016 Dec;74(10):443-448.

Abstract

Background: D-dimer is routinely measured as part of the clinical diagnosis algorithms for venous thromboembolism (VTE). In these algorithms, low D- dimer cut-off values are used to generate a dichotomous test result that is sensitive, but very non-specific for VTE. A consequence of any test dichotomisation is loss of information that is hidden in the continuous spectrum of results. For D-dimer, the information conveyed by extremely elevated results may be particularly relevant. Our aim was to assess the differential diagnosis of extremely elevated D-dimer levels in a hospital setting.

Methods: Retrospective cohort study of patients > 18 years with an extremely elevated (> 5000 μg/l; > 10x cut-off to exclude VTE) D-dimer test result. Electronic medical records were reviewed for diagnoses.

Results: A total of 759 extremely elevated D-dimer results were identified. After exclusion of 120 duplicate cases, 53 patients undergoing cardiopulmonary resuscitation, and 5 cases without diagnostic information, 581 cases were analysed. Their D-dimer ranged between 5030 and 239,000 μg/l, with a mean of 17,598 μg/l (SD 22,972 μg/l). Altogether, 89% of these patients had a diagnosis of VTE, sepsis and/or cancer. The prevalence was highest for pulmonary embolism (183 patients; 32%), followed by cancer (168 patients; 29%), sepsis (142 patients; 24%), trauma/surgery (142 patients; 24%), and deep vein thrombosis (73 patients; 13%).

Conclusion: Although D-dimer testing has a reputation for being very non-specific, an extremely elevated D-dimer is uniquely associated with severe disease, mainly including VTE, sepsis and/or cancer. These results suggest that, even if sharply elevated D-dimers are a seemingly solitary finding, clinical suspicion of severe underlying disease should be maintained.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Diagnosis, Differential
  • Female
  • Fibrin Fibrinogen Degradation Products / metabolism*
  • Humans
  • Male
  • Middle Aged
  • Neoplasms / diagnosis
  • Neoplasms / metabolism*
  • Pulmonary Embolism / diagnosis
  • Pulmonary Embolism / metabolism*
  • Retrospective Studies
  • Sensitivity and Specificity
  • Sepsis / diagnosis
  • Sepsis / metabolism*
  • Venous Thrombosis / diagnosis
  • Venous Thrombosis / metabolism*

Substances

  • Fibrin Fibrinogen Degradation Products
  • fibrin fragment D