Chest computed tomography findings of adult patients with antimelanoma differentiation-associated protein 5 antibody-positive interstitial lung disease

Objectives Interstitial lung disease (ILD) associated with the antimelanoma differentiation-associated protein 5 (anti-MDA5) antibody is a rapidly progressive disease that requires timely, aggressive treatment. However, prompt diagnosis is difficult due to the longer time required for antibody detection. This study described the computed tomography (CT) findings of anti-MDA5 antibody-positive ILD (anti-MDA5-ILD). Methods CT findings of 20 patients (7 men, 13 women; mean age, 53.6 +/- 13.5 years) with anti-MDA5-ILD were retrospectively reviewed. All patients had clinical diagnoses of dermatomyositis, and 14 patients presented with amyopathic findings. Results Bilateral ground-glass attenuation, air-space consolidation, and reticular shadows were observed in 20 (100%), 15 (75%), and 3 (15%) patients, respectively. The spread of air-space consolidation was 6.0 +/- 5.6% (mean +/- standard deviation). Univariate analysis revealed that high Krebs von den Lungen-6, high spread of consolidation, low partial pressure of oxygen, and low forced vital capacity were significant predictors for poor survival. The final radiological diagnoses were nonspecific interstitial pneumonia and organising pneumonia (OP) in 2 (10%) and 16 (80%) patients, respectively. Further, 30% of OP patients showed fibrosis. Conclusion The characteristic CT findings of patients with anti-MDA5-ILD were ground-glass attenuation, air-space consolidation, and less reticulation. These CT findings were compatible with those of OP.