Anti-MDA5 antibody positivity

What it means

The presence of autoantibodies in the serum that react to Anti-MDA5 (Anti-melanoma differentiation-associated proteine 5).

Anti-MDA5 antibodies are myositis-specific autoantibodies, that are specific for clinically amyopathic dermatomyositis (CADM), an uncommon presentation of idiopathic inflammatory myositis, which is associated with rapidly progressive interstitial lung disease.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Increased level of anti-melanoma differentiation-associated protein 5 antibodies