Rheumatoid vasculitis (also known as rheumatic vasculitis) is a type of inflammatory disease of blood vessels, most often capillaries and arterioles of small arteries. Rheumatic vasculitis is caused by collagenous, immune-related damage. It occurs in various organs, but most often in the skin. In addition, vasculitis causes severe thinning of the vascular wall and an increase in permeability (the ability of arterioles and capillaries to penetrate from the blood into the tissues of metabolites of mineral substances of cell breakdown products).