Vasculitis (inflammation of blood vessels) can occur as the main disease (primary vasculitis), or as a complication of another disease (secondary vasculitis). It can just affect one part (localized vasculitis) or multiple parts of (systemic vasculitis) of the body.
There are almost 20 types of ‘primary systemic vasculitis’ and they are classified as to whether they mainly affect small, medium or large sized blood vessels. Within the small vessel subgrouping the most common forms of vasculitis are associated with abnormal proteins in the blood called ANCA (antineutrophil cytoplasmic antibodies). This subgroup comprises Granulomatosis with Polyangiitis (formerly Wegener’s Granulomatosis), Microscopic Polyangiitis and Eosinophilic Granulomatosis with Polyangiitis (formerly Churg-Strauss). Other common types are those that affect large blood vessels, such as Giant Cell (temporal) Arteritis and Takayasu’s Arteritis
Individual variants of vasculitis are defined by the parts of the body affected (for example, Granulomatosis with Polyangiitis typically affects the nose, lungs and kidneys), by features seen on tissue biopsy and by the pattern of blood test abnormalities. Direct imaging of blood vessels or other tests help in the diagnosis of medium and large vessel vasculitis.
Who gets it?
We don’t really know.
Different variants affect different age groups, ANCA associated vasculitis is most common in those over 50 years but can affect younger patients, while Kawasaki disease mainly affects young children and Takayasu’s Arteritis, young adults. Giant Cell Arteritis is most common in those over 70 years old.
Rates of vasculitis appear to vary geographically., For example Granulomatosis with Polyangiitis (Wegener’s) and Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss) seems to be more common in more Northern countries. Ethnicity is also a factor with Chinese and Japanese populations having more Microscopic Polyangiitis and Takayasu’s Arteritis and less Granulomatosis with Polyangiitis (Wegener’s) and Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss).
Is it hereditary or family tendency?
There is a complex genetic predisposition which is not fully understood. Family members only have a slightly increased risk of developing Vasculitis when compared to the general population, so it is not regarded as an inherited disease.
What causes it?
A consensus view is that an environmental agent, such as a virus, triggers the disease in a genetically susceptible individual.
Environmental exposure to silica in coal mining increases the likelihood of some forms of vasculitis but other environmental factors have not been identified. Bacterial infections, s, have also been implicated.
How would you know you had it?
This varies between the variants of Vasculitis.
Typically there is a period of time (prodromal phase) of fluctuating symptoms including tiredness, muscle aches, joint pains, headaches, fevers, sweats and weight loss.
Then there are features depending on the particular part of the body under attack. . Granulomatosis with Polyangiitis (Wegener’s) commonly involves the nose, sinuses and ears with nasal stuffiness, bleeding, sinus pain and deafness. Lung involvement could cause a bloody productive cough or breathlessness. Kidney involvement causes no obvious symptoms until the kidneys are badly damaged, but can be detected at an early stage by a simple urine ‘dip stick’ test.
How would it be diagnosed?
Vasculitis can be hard to diagnose, the key is suspicion
It should at least be considered in patients with an unexplained illness where there is evidence of ‘inflammation’ in the blood .
Then there are many specific scenarios when it should be suspected which depend on the part of the body affected. For example, it should be suspected in anyone with a urine test suggesting kidney disease or in a patient with unexplained shadows on a chest X-ray or the development of asthma in adulthood.
Once it has been suspected, the doctor should consider referral to a specialist who may then launch quite a wide range of investigations that may ultimately lead to the confirmation of vasculitis or the discovery of an alternative disease.
Can it be treated?
Yes. Treatment is quite complicated and its success depends on the type of vasculitis, the parts of body affected and the severity. In most cases vasculitis can be controlled. Quite often the vasculitis will have already caused damage that cannot be reversed though, for example change in shape of the nose or lung and kidney scarring., Long term treatment can help prevent further damage occurring. Most patients will feel very unwell when their Vasculitis is untreated and it can take many months for them to feel stronger after treatment is started. In the longer term, patients continue to report significant impairments in quality of life as a result of accrued damage and drug side effects.
Does it ever go away?
In some variants.
Again this depends on the type. Some forms of Vasculitis only occur once and do not recur, for example Henoch-Schonlein Purpura in children. Other types are more likely to remain present but controlled through treatment. The disease may flare, especially as treatment is reduced or withdrawn.
Are you at risk of any other illnesses?
If a part of the body is damaged, for example the kidneys, then a patient will suffer the consequences of kidney failure. Treatment is associated with a number of early and late side-effects and make patients susceptible to infections. Over the long term there is an increased risk of cardiovascular disease (heart disease and stroke) and of cancer.
Is it likely to shorten your life?
This depends on the type of vasculitis, its severity and whether damage has occurred. Damage to the kidney is the most common cause of a shortened life span. Very severe vasculitis presentations can be fatal.
Who should you see for help?
Vasculitis patients should be treated by doctors experienced in the disease. Vasculitis doctors are most commonly trained as rheumatologists (joint doctors) or nephrologists (kidney doctors) but other specialists may have developed an interest and experience in the disease. Some but not all many hospitals have specialised Vasculitis services.