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Highlights & Basics
- Organizing pneumonia (OP) is an inflammatory disorder involving both the peripheral bronchioles and alveoli simultaneously. It has distinctive radiographic findings, histologic features, and response to corticosteroids (unlike usual interstitial pneumonia).
- OP may be caused by multiple insults such as medication, infection, rheumatologic disease, autoimmune disease, post transplantation, radiation, and environmental causes. In cryptogenic organizing pneumonia, a cause cannot be elicited after a careful history, examination and pertinent laboratory studies.
- High-resolution chest computed tomography scan shows bilateral patchy triangular ground-glass opacities with air bronchograms usually located peripherally.
- Most often, diagnosis is made using clinico-radiologic criteria and usually in the setting of a multidisciplinary team. However, lung biopsy may be required to establish the definitive diagnosis in patients with unusual findings.
- Cryptogenic OP may require treatment, and prednisone is the most commonly used drug.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Images
Medium-powered pathology slide showing circular and branching bronchioles filled with polypoid plugs of granulation tissue and alveoli filled with organizing pneumonia
Algorithmic approach to organizing pneumonia. ∗ A formal MDD may not be required in all cases, especially if the combination of clinical context and radiographic pattern is sufficiently convincing of the OP diagnosis. In such cases, a discussion between the physician and the radiologist is strongly encouraged. CRP = C-reactive protein; DAH = diffuse alveolar hemorrhage; Dx = diagnosis; ESR = erythrocyte sedimentation rate; GGO = ground-glass opacification; HRCT = high-resolution CT; MDD = multidisciplinary discussion; nl Pro-Cal C = normal procalcitonin; nl WBC = normal WBC; OP = organizing pneumonia
Chest x-ray showing bilateral patchy infiltrates
High-resolution chest CT showing bilateral ground-glass opacities and a posterior triangular-based infiltrate with an air bronchogram
Citations
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