D-dimer Testing in Upper Extremity DVT
Yes, D-dimer levels are typically elevated in patients with upper extremity deep vein thrombosis (DVT), and a negative D-dimer test can effectively rule out upper extremity DVT in patients with low pretest probability. 1
Diagnostic Value of D-dimer for Upper Extremity DVT
Sensitivity and Specificity
- D-dimer has a sensitivity of approximately 92% (95% CI: 73-99%) for upper extremity DVT 2
- Specificity is around 60% (95% CI: 52-67%) 2
- Negative predictive value is excellent at 98% (95% CI: 93-100%) 2
Clinical Application
D-dimer testing is most valuable in patients with:
- Low pretest probability/unlikely clinical probability (≤10%) 1
- Outpatient settings where prevalence of disease is lower 3
Recommended Diagnostic Approach
For Patients with Low Pretest Probability (≤10%):
- Start with D-dimer testing 1, 4
- If D-dimer is negative → No upper extremity DVT (can safely rule out) 1
- If D-dimer is positive → Proceed to duplex ultrasound 1
- If D-dimer is not available → Proceed directly to duplex ultrasound 1
For Patients with High Pretest Probability (≥40%):
- Either start with D-dimer followed by duplex ultrasound/serial duplex ultrasound, OR
- Perform duplex ultrasound/serial duplex ultrasound alone 1
- Important: Never use a positive D-dimer alone to diagnose upper extremity DVT 1, 4
Important Clinical Considerations
Limitations of D-dimer Testing
- D-dimer has limited utility in hospitalized patients 1
- Certain populations (post-surgical, pregnant) frequently have positive D-dimer results with standard thresholds 1
- Tissue injury can cause persistent D-dimer elevation that may not normalize for extended periods 5
Extremely Elevated D-dimer Levels
- While D-dimer is generally considered non-specific, extremely elevated levels (>5000 μg/L) are strongly associated with serious conditions 6:
- Venous thromboembolism
- Sepsis
- Cancer
Practical Implementation
- Use a highly sensitive D-dimer assay when following this strategy 1
- Ensure test results will be obtained in a timely manner 1
- Consider that the cost of D-dimer screening should be offset by avoiding unnecessary ultrasound examinations 1
- Suboptimal D-dimer results may require repeat testing 1
The American Society of Hematology (ASH) guidelines specifically recommend against using a positive D-dimer alone to diagnose upper extremity DVT regardless of pretest probability, as it requires confirmation with imaging studies 1, 4.