Vasculitis

What is it?

Vasculitis refers to a rare group of conditions where there is inflammation of blood vessels. There are various different types of vasculitis, which can be classified either according to the size of the blood vessels damaged or according to the part of the body affected, and also whether there is any underlying disease. It is also useful to know whether the patient has the ANCA (anti-neutrophil cytoplasmic) antibody in the blood. Vasculitis can be divided accordingly in various ways:

Classifications

  • Whether it is localised or generalised
  • Vessel size
  • Underlying cause (e.g. drugs, infection, lupus (SLE), rheumatoid arthritis)
  • Whether the ANCA test is positive

There is a group of vasculitic conditions known as primary systemic vasculitis, so called because they affect the whole body (systemic), and are primary (there is no underlying condition). Examples of these conditions are Wegener’s granulomatosis, microscopic polyarteritis/polyangiitis and Churg-Strauss syndrome.

VESSEL SIZEANCA-POSITIVEANCA-NEGATIVE
Large Giant cell arteritis
Takayasu’s arteritis
Medium Polyarteritis nodosa
Kawasaki’s disease
SmallWegener’s granulomatosis
Microscopic polyarteritis
Churg-Strauss syndrome
Henoch-Schonlein purpura
Hypersensitivity vasculitis
Cryoglobulinaemic vasculitis
Symptoms

Symptoms of vasculitis can be non-specific and this can be why vasculitis may be difficult to diagnose in some cases. Symptoms may include general tiredness, loss of appetite, weight loss and fevers. More specific symptoms include bleeding from the nose, excessive nasal crusting, sinus pains, collapse of the nasal bridge in advanced cases, cough, coughing up blood, breathlessness, rashes, joint pains, numbness and tingling in the hands or feet.  Vasculitis may also affect the kidneys, but this may often go undetected until the kidney damage is quite advanced. Involvement of the kidney carries a worse outlook.

Testing

Initial testing may involve:

  • Full Blood Count (FBC) – this test is used to look for complications of the disease and its treatment. It evaluates the patient’s red cells and haemoglobin concentration (reduced in anaemia) and checks the white blood cell count which can be increased in infection, and reduced with some treatments
  • Erythrocyte sedimentation rate (ESR) – this test indicated the presence of inflammation in the body and helps monitor the activity of the disease 
  • C-reactive protein test (CRP) - this test also indicates inflammation and tests for activity of the disease.
  • Urea & electrolytes / creatinine – assessment of kidney function
  • Liver function tests (LFT) – assessment of liver function
  • Urine dipstick, microscopy – looks for presence of protein, red and white cells in the urine, which can indicate inflammation in the kidney
  • ANCA – anti-neutrophil cytoplasmic antibody is an useful marker for primary systemic vasculitis conditions

Subsequent testing may involve:

  • Tissue biopsy – the gold standard test for diagnosis of vasculitis is to take a biopsy of affected organ e.g. skin, kidney, nerve
  • Radiological imaging can be helpful e.g. chest x-ray, CT scan chest, sinuses
  • Nerve conduction studies or nerve biopsy may be useful if there are symptoms of numbness or tingling
  • In some types of vasculitis, examination of the blood vessels by angiography can be useful such as angiography of the bowel in polyarteritis nodosa

The blood tests will enable the doctor to assess whether there is any inflammation in the blood which would suggest vasculitis, and importantly the urine tests will help assess whether there is kidney damage.

In the 1980’s, a new blood test was introduced which was associated with a number of vasculitic conditions, in particular the group of primary systemic vasculitis mentioned above. The ANCA antibodies are directed against a blood cell called the neutrophil and more particularly against the cytoplasm (the inner part) of the cell. While this is a helpful test, we now know that it is not diagnostic by itself. Tissue biopsy remains very important and is still the gold standard to diagnose vasculitis.

Treatment

The treatment of the vasculitis depends on

  • the exact type of vasculitis
  • whether there is an underlying cause
  • the range of organ involvement, especially if there is kidney involvement

In some cases, if an underlying cause can be identified, treatment should be directed towards this cause. This may include the withdrawal of a triggering drug. If infection is the underlying cause, then this should be treated. An example of an underlying cause of vasculitis is Hepatitis C infection which can cause a particular form called cryoglobulinaemic vasculitis.

The treatment often involves the use of drugs which suppress the immune system, because vasculitis is caused by an immune system behaving in a hyperactive and inappropriate fashion. Corticosteroids are an example of a type of specific immunosuppressive drug used to treat vasculitis. Corticosteroids, not to be confused with anabolic steroids used by athletes, are normally produced by the body’s own adrenal glands. There are synthetic forms given by mouth (e.g. prednisolone) or intravenously (e.g. methylprednisolone), which are very effective in treating vasculitis. However in the long term they have side effects such as weight gain, reducing bone density, and increased risk of diabetes and high blood pressure. In order to reduce the steroid requirements, and to control the disease, other immunosuppressive drugs may be used instead.

For patients with primary systemic vasculitis, immunosuppressive drugs are always required. More intensive immunosuppressive regimens are used if there is kidney involvement, or there is life-threatening organ involvement. Examples of the immunosuppressive drugs used in primary vasculitis are cyclophosphamide, methotrexate, and azathioprine.

These drugs do carry side effects, but vasculitis is potentially very serious. The choice of drug in each patient is only decided after paying due consideration to the severity of the disease. All immunosuppressive drugs lead to the potential for reduction in blood cell counts – low red blood cells, low white cells, low platelets and hence carry an increased risk of infection,. Frequent monitoring of blood tests, such as blood cell counts and liver function tests, helps to detect such side effects early. The use of other medications, such as folic acid in patients taking methotrexate, can protect the individual from other side effects of these treatments.