Autoimmune vasculitis is an inflammation of blood vessels, characterised by ischemia, necrosis, and occlusive changes. This type of vasculitis can affect any blood vessel from large to small.
The disorder can be classified according to the size of blood vessels damaged, according to the part of the body affected, and whether there is any underlying cause or disease, such as drugs, lupus erythematosus (SLE) or rheumatoid arthritis. Clinical manifestations of the specific vasculitic diseases are diverse and depend on the size of vessels involved and of the organs affected by ischemia. In autoimmune vasculitis, an autoimmune process is responsible for a life-threatening inflammation of the blood vessel walls.
Initial laboratory testing in case of suspected autoimmune vasculitis includes: full blood count (FBC), erythrocyte sedimentation rate (ESR), C-reactive protein test (CRP), urea and electrolytes / creatinine, liver function tests (LFT), urine dipstick and microscopy, and testing for ANCA, which are very useful markers for primary systemic vasculitis conditions.