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Published on: September 6, 2024
Pulmonary embolism despite negative ELISA D-dimer: a case report.
Marc E Breen1, Marc Dorfman, Shu B Chan
1Emergency Medicine Residency Program, Resurrection Medical Center, Chicago, Illinois 60631, USA.
The Journal of Emergency Medicine
|May 13, 2008
Summary
A pulmonary embolism (PE) can be fatal but is treatable if caught early. Relying solely on D-dimer tests may miss PE in some patients, emphasizing the need for clinical suspicion.
Area of Science:
- Cardiology
- Pulmonology
- Diagnostic Imaging
Background:
- Pulmonary embolism (PE) is a life-threatening condition often presenting with variable symptoms.
- Early diagnosis of PE is crucial for effective treatment.
- The D-dimer assay is commonly used to rule out PE, but its safety is limited to low-risk populations.
Observation:
- A 26-year-old woman presented with recurrent chest pain and dyspnea over two weeks.
- Initial and follow-up enzyme-linked immunosorbent assay (ELISA) D-dimer tests were normal.
- Computed tomography (CT) scan confirmed PE during her second emergency department visit.
Findings:
- The case demonstrates that normal ELISA D-dimer results do not reliably exclude PE in all patients.
- Clinical presentation and suspicion are critical components in diagnosing PE, even with negative D-dimer assays.
Implications:
- Over-reliance on ELISA D-dimer assays for PE exclusion can lead to misdiagnosis and delayed treatment.
- Integrating clinical probability assessment with diagnostic testing is essential for accurate PE diagnosis.
- This case underscores the importance of maintaining a high index of suspicion for PE in patients with concerning symptoms.
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