What is the main diagnostic test for allergic vasculitis?

Blood testing. Testing for systemic signs of inflammation with c-reactive protein levels or erythrocyte sedimentation rate is often performed. Testing for auto-immune antibodies such as anti-nuclear antibodies (ana screening) or rheumatoid factor may be needed. In addition, evidence of complement protein cascade activation (ch-50) may be useful to detect active inflamation periods. Biopsy is the best test.
Allergic vasculitis. The diagnosis is typically made by history and clinical appearance. If diagnosis is in question, ESR testing and/or biopsy may be considered. See the following website: http://www.Ncbi.Nlm.Nih.Gov/pubmedhealth/pmh0001877/.

Related Questions

Does allergic vasculitis usually have long-term complications?

YES, IT MAY. First, what exact vasculitis you mean. If it is churg-strauss, it can cause damage in lungs, some nerves, even leading to paralysis, heart problems. Kidneys - rarely. Even allergic vasculitis affecting mainly the skin may cause complications inside the body. Even allergic vasculitis that is usually limited to the skin (see website below), can be associated with damage to internal organs. Read more...
Allergic vasculitis. See the following website: http://www.Ncbi.Nlm.Nih.Gov/pubmedhealth/pmh0001877/.