What is Central Nervous System Vasculitis?
Central nervous system (CNS) vasculitis is inflammation of blood vessel walls in the brain or spine. (The brain and the spine make up the central nervous system.) CNS vasculitis often occurs in the following situations:
- accompanied by other autoimmune diseases such as systemic lupus erythematosus, dermatomyositis, and, rarely, rheumatoid arthritis
- infection, such as viral or bacterial
- systemic (affecting the whole body) vasculitic disorders (Wegener’s granulomatosis, microscopic polyangiitis, Behçet’s syndrome);
- it can be without any associated systemic disorder. In this case, the vasculitis is only confined to the brain or the spinal cord; and, it is referred to as primary angiitis of the CNS (PACNS).
What is the cause of Central Nervous System Vasculitis?
How the vessels in the brain become inflamed is not entirely clear. In some diseases, abnormal antibodies (autoantibodies) and white blood cells attack vessel walls and cause inflammation and destruction of the vessel wall. Infection caused by a virus can also cause CNS vasculitis.
Is Central Nervous System Vasculitis dangerous?
CNS vasculitis can be a serious condition. The inflamed vessel wall can block the flow of oxygen to the brain, causing a loss of brain function. In some cases, CNS vasculitis is life-threatening.
Symptoms of CNS vasculitis can include the following:
- severe headaches that last a long time
- strokes or transient ischemic attacks (“mini-strokes”)
- forgetfulness or confusion
- problems with eyesight
- encephalopathy (swelling and damage to the brain)
- sensation abnormalities
The diagnosis of vasculitis, including CNS vasculitis, is based on a person’s medical history, symptoms, a complete physical examination, and the results of special laboratory tests. Blood abnormalities that are found in vasculitis include:
- anemia (low red blood cell count)
- high white blood cell count
- high platelet count
- kidney or liver problems
- allergic reactions
- finding immune complexes in the circulating blood
- identifying abnormal antibodies in the blood
- an increase in blood markers of inflammation
In PACNS, when the vasculitis is only confined to the brain or spinal cord, the above symptoms and signs are often lacking and patients present with symptoms of CNS vasculitis only.
Other useful tests may include X-rays, tissue biopsies (taking a sample of tissue to study under a microscope), and blood vessel scans. The physician might also want to examine the spinal fluid to see what is causing the inflammation or assess the degree of inflammation. This test is often performed in CNS vasculitis.
To help in the diagnosis of CNS vasculitis, the physician may order a magnetic resonance images or angiogram of the brain. An angiogram can show which blood vessels are narrowed or enlarged.
Because other conditions can cause some of the same brain vessel abnormalities as CNS vasculitis, a brain biopsy may be the only way to make certain of a diagnosis. A brain biopsy can distinguish between CNS vasculitis and other diseases that may have similar features.
What major condition resembles Central Nervous System Vasculitis?
Reversible Cerebral Vasoconstriction Syndromes (RCVS) comprises a group of diverse conditions, all characterized by spasm of the brain vessels. The main symptom of RCVS is sudden, severe headaches. Strokes or bleeding into the brain may or may not be present. RCVS was previously named benign angiopathy of the central nervous system (BACNS) but the term was recently changed to include other similar disorders.
RCVS is a major mimic of central nervous system vasculitis and should be distinguished from it given the difference in the treatment and the outlook between the two disorders.
Abnormality in the control of brain blood vessel pressure is believed to be the critical element in the pathophysiology of RCVS. The alteration in vascular tone may be spontaneous or evoked by various exogenous or endogenous factors. There is no evidence of vasculitic changes in the brain tissue in RCVS.
It is essential for clinicians evaluating patients for CNS vasculitis to be aware of RCVS and to distinguish it from CNS vasculitis. Treatment of RCVS does not require immunosuppressive medications (chronic use of high dose steroids and chemotherapy), as is the case with CNS vasculitis.
CNS vasculitis is usually treated with steroids. High-dose steroids such as prednisone, in combination with cyclophosphamide (a medication that decreases the immune system’s response to autoimmune diseases), are generally used. In some cases, high-dose steroids alone are tried first; if that does not effectively treat the disease, cyclophosphamide is added. Treatment must be continued for a prolonged period, sometimes for life.
If the patient has another illness (such as lupus) that is related to the vasculitis, then that illness also needs to be treated.
Revision: September 2012