Objective: To assess the high-resolution computed tomography appearances of drug-associated organizing pneumonia (OP).
Materials and methods: Nine patients with clinical and biopsy proven drug-associated OP were included in the study. High-resolution computed tomography exams were retrospectively reviewed by 2 observers for the presence, extent, and distribution of parenchymal abnormalities.
Results: The commonest findings consisted of air space consolidation (n = 8) and ground-glass opacification (n = 7). The air space consolidation was bilateral and asymmetric in 7 patients, symmetric in 1 patient and in all cases involved mainly the peribronchial or subpleural regions or both. The ground-glass opacities were predominantly bilateral and asymmetric in 6 patients and unilateral in 1 patient. They had a patchy distribution in 4 patients, were diffuse in 2 patients, and subpleural in 1 patient.
Conclusion: Drug-associated OP most commonly presents with bilateral, asymmetrical air space consolidation in a predominantly peribronchial and subpleural distribution.