Comparison of severe COVID-19 pneumonia and anti-MDA-5 antibody-positive DM-RP-ILD
| Severe COVID-19 pneumonia | Anti-MDA5 antibody-positive DM-RP-ILD | |
| Clinical behaviour | Acute. | Rapidly progressive. |
| Trigger | SARS-CoV-2. | Possible virus infection. |
| Ethnic and/or geographical differences | All ethnicities are susceptible and vulnerable. | More severe in Asian populations. |
| Typical rash | No. | Gottron’s rash, skin ulceration, palmar papule. |
| Muscle involvement | Myalgia and myositis. | Amyopathy or hypomyopathy. |
| Predictive factors | Older age, male sex, comorbidities, high levels of proinflammatory cytokine. | High titre of anti-MAD5 antibody, hyperferritinaemia, high levels of proinflammatory cytokine. |
| Cytokine/chemokine profile | IL-1, IL-2, IL-6, IL-10, IL-18, IP-10, MCP-1, GM-CSF, IFN-γ, TNF-α. | IL-1β, IL-4, IL-6, IL-8, IL-10, IL-18, IP-10, IFN-α, IFN-γ, TNF-α. |
| HRCT pattern | GGO, consolidation, AIP. | NSIP, OP. |
| Treatment | ||
| Glucocorticoid | Possible benefit. | Benefit. |
| Immunosuppressant | No data. | Benefit. |
| Anticytokine therapy | Possible benefit. | Benefit. |
| Antifibrotic agents | No data. | Probable benefit. |
| Plasmapheresis | Possible benefit | Probable benefit. |
AIP, acute interstitial pneumonia; DM-RP-ILD, dermatomyositis-associated rapidly progressive interstitial lung disease; GGO, ground glass opacity; GM-CSF, granulocyte-macrophage colony stimulating factor; HRCT, high-resolution CT; IFN, interferon; IL, interleukin; IP-10, interferon-inducible protein-10; MCP-1, monocyte chemotactic protein-1; MDA-5, melanoma differentiation-associated gene 5; NSIP, non-specific interstitial pneumonia; OP, organising pneumonia; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; ;TNF-α, tumour necrosis factor alpha.