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Published on: April 14, 2011
Influenza A infection simulating pulmonary embolism.
JAMA
|September 12, 1977
Summary
Pulmonary perfusion scans may misdiagnose pulmonary embolism in patients with influenza A. Viral infections can mimic embolism symptoms, leading to incorrect diagnoses if scans are solely relied upon.
Area of Science:
- Pulmonary Medicine
- Infectious Diseases
- Diagnostic Imaging
Background:
- Pulmonary embolism (PE) diagnosis typically relies on clinical history, chest X-ray, and perfusion scans.
- Perfusion scans are crucial for identifying pulmonary perfusion abnormalities suggestive of PE.
Observation:
- Four young women initially presented with symptoms and positive perfusion scans suggesting pulmonary embolism.
- Subsequently, these patients developed respiratory viral infections, specifically influenza A.
- Further diagnostic evaluations, including angiography, contradicted the initial PE diagnoses.
Findings:
- Convalescent-phase complement-fixation titers confirmed influenza A infection in all patients.
- Pulmonary perfusion scan abnormalities were observed in the context of influenza A infection.
- Angiography did not support the presence of pulmonary emboli in these cases.
Implications:
- Reliance solely on pulmonary perfusion scans can lead to misdiagnosis of pulmonary embolism.
- Influenza A can present with symptoms and imaging findings that mimic pulmonary embolism.
- Clinical correlation and consideration of alternative diagnoses like viral infections are essential for accurate PE diagnosis.
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