Immune complex small vessel vasculitis is caused by an immune reaction to foreign substances in the body which results in inflammation of the small blood vessels. These foreign substances can be proteins, bacteria, viruses, or other antigens.
Diagnosis is made by taking a history of the patient’s symptoms, physical exam, imaging studies (such as MRI and CT scan), and blood tests which can detect antibodies to the foreign substances.
Differential diagnoses include other types of vasculitis, such as giant cell arteritis, polyarteritis nodosa, and Kawasaki disease.
Treatment may include medications such as corticosteroids and immunosuppressants to reduce inflammation and relieve symptoms.
Prognosis is usually good with appropriate treatment, however, the symptoms may recur if the underlying cause is not addressed.