Patients with markedly elevated D-dimer who do not have pulmonary embolism

Area of Science:

• Medical Diagnostics
• Clinical Pathology
• Cardiovascular Medicine

Background:

• Elevated D-dimer levels are commonly associated with pulmonary embolism (PE).
• However, markedly raised D-dimer in patients with a negative CT pulmonary angiogram (CTPA) requires further investigation.
• Identifying alternative diagnoses is crucial for appropriate patient management.

Purpose of the Study:

• To investigate the causes of significantly elevated D-dimer levels in patients where PE has been ruled out by CTPA.
• To specifically examine the prevalence of new cancer and aortic dissection in this patient group.

Main Methods:

• Retrospective analysis of 1000 consecutive patients suspected of PE between 2012 and 2016.
• Focus on patients in the top D-dimer quintile (7.5-260x upper limit normal) with negative CTPA findings.
• Review of case records to determine the underlying causes of elevated D-dimer.

Main Results:

• Eighty-five patients met the inclusion criteria.
• Infection was the most common cause (41.2%), followed by cardiovascular disease (14.1%, including two cases of undiagnosed aortic dissection), surgery/trauma (14.1%), and new/active cancer (10.6%).
• A significant proportion (43.5%) died within 2 years, with poorer survival in cancer patients.

Conclusions:

• Extremely high D-dimer levels in patients without PE can signify serious, potentially missed diagnoses such as cancer and aortic dissection.
• These findings highlight the importance of considering alternative diagnoses beyond venous thromboembolism.
• Further research is needed to establish optimal diagnostic pathways for patients with markedly elevated D-dimer levels and no evidence of PE.