Vasculitis refers to inflammation of the vasculature. This inflammation can lead to blockage of the blood vessels that then deprives various organs and tissues of vital blood supply.
When the nerves that supply the peripheral nervous system are affected due to inflammation, a patient may develop vasculitic neuropathy.
Vasculitic neuropathy usually arises due to systemic vasculitis that may affect the kidneys, lungs, skin and other organs. Examples of systemic conditions that can cause vasculitic neuropathy include polyarteritis, Churg-Strauss syndrome, Wegener granulomatosis and microscopic polyangitis.
The condition can also occur secondary to inflammatory diseases such as rheumatoid arthritis and systemic lupus erythematosus. In these conditions, macrophages and lymphocytes contribute to vascular wall damage.
The type and location of the nerves involved determines the symptoms of this condition, which may cause dysfunction of both the sensory nerves and the motor nerves. Unlike other forms of peripheral neuropathy, vasculitic neuropathy can give rise to symptoms in an asymmetric manner and affect one body part in particular. Some examples of the symptoms that may arise include:
- Unusual sensations or paresthesias
- Weak limb muscles
Diagnosis is suspected based on symptoms, clinical examination and laboratory tests. Examples of the tests that may be performed include electromyography to study nerve conduction, skin biopsy to check for cutaneous innervation and histopatholgical analysis of nerve and muscle tissue samples.
Treatment involves correction of the underlying inflammation in the blood vessels, which can usually be achieved with immunomodulatory agents. Corticosteroids are usually the first treatment to be prescribed but the risks associated with long-term use of these drugs means patients are usually moved on to other therapies. For acute attacks, intravenous immune globulins or plasma exchange can sometimes be effective. The pain associated with neuropathy may be treated using anti-epileptic medications, pain relievers or antidepressants.