Interstitial Lung Disease with Anti-melanoma Differentiation-associated Protein 5 Antibody: Rapidly Progressive Perilobular Opacity

OBJECTIVE: Rapidly progressive interstitial lung disease (RP-ILD) with anti-melanoma differentiation-associated protein 5 (MDA5) antibody potentially presents with a fatal clinical course and requires early intensive treatment. Recently, perilobular opacity was reported to pathologically correspond to the acute phase of diffuse alveolar damage in RP-ILD with anti-MDA5 antibody. We aimed to investigate whether or not perilobular opacity was a common radiological finding in RP-ILD patients with anti-MDA5 antibody. METHODS: We conducted a retrospective review of the medical records of eight consecutive patients with RP-ILD with anti-MDA5 antibody. The clinical features and radiological findings of follow-up computed tomography (CT) during the course of their disease were evaluated. RESULTS: Among eight RP-ILD patients with anti-MDA-5 antibody, six showed perilobular opacity in the lower lobes, and the remaining two had only consolidation on high-resolution CT. Of note, the perilobular opacity in all six patients thickened and progressed to consolidation with a loss of lung volume in a short period. Despite intensive treatment, 6 patients (75%) died within 100 days after the first visit. Notably, the two patients with consolidation presented with a very rapid clinical course and died in 13 days each. In the two survivors, the perilobular opacity and consolidation recovered with improvement in the loss of lung volume. CONCLUSION: Rapidly progressive perilobular opacity that thickens and progresses to consolidation is characteristic of RP-ILD with anti-MDA5 antibody. Chest physicians should immediately check the status of anti-MDA-5 antibody in order to initiate early aggressive therapy in RP-ILD patients with rapidly progressive perilobular opacity.