Blood vessels take life-giving blood to every part of the body – so you're in trouble if those vessels are inflamed.

But such inflammation can occur in any of the vessels, resulting in an auto-immune disease called vasculitis – which literally means 'inflammation of the blood vessels'.

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Any organ in the body can be affected, including the kidneys, lungs, heart, brain and nervous system.

It's a rare and little-known problem, and the charity Vasculitis UK is trying to draw attention to it through Vasculitis Awareness Month, which ends this weekend.

There’s no single test for any of the types of vasculitis, there's no cure and – at its worst – it can be fatal.

What is vasculitis?

Vasculitis is actually a series of conditions collectively known as vasculitides – in which the body's immune system attacks blood vessels by mistake.

The damaged cells release chemicals that cause blood vessels to leak fluid into the tissues, leading to swollen blood vessel walls and narrowed vessels.

Blood flow to tissues and organs is reduced or blocked, and if the blood vessel wall becomes weak, bleeding can occur.

John Mills, chairman of Vasculitis UK, explains: “Systemic vasculitis is a term used to describe a group of 18 rare autoimmune diseases – all of which involve inflammation of the lining of the blood vessel, which can cause blockage of the blood vessels or make them leaky.”

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It's estimated that around 3,000 people in the UK develop a form of vasculitis every year, generally from the age of 50 onwards, although young people and infants can also be affected.

Any blood vessel can become inflamed, from large arteries (arteritis) to small blood vessels, in any place in the body. The larger the blood vessels affected, the more damage there may be.

Vasculitis symptoms

Symptoms depend on the organs involved, although they can generally include tiredness, weakness, loss of appetite, weight loss, and fever. Such symptoms, of course, apply to many other diseases too, which can make it very difficult to diagnose vasculitis.

In addition, there are numerous other symptoms, depending on the body system the vasculitis affects. These include:

  • Respiratory system - breathlessness, wheeze, dry cough or coughing up blood.
  • Ear, nose and throat - hearing problems, nasal crusting, nosebleeds, sinus pain (which may be felt as headaches or facial pain), or a hoarse voice.
  • Skin - rashes, ulcers, and necrosis (tissue death).
  • Eyes - bloodshot, painful, dry or gritty eyes, visual loss or other vision changes.
  • Joints - pain and swelling in joints.
  • Nervous system - loss of sensation, weakness, unusual painful symptoms in hands and feet (hotness, pins and needles or 'electric shocks'), and (albeit rarely) paralysis or stroke.
  • Gastrointestinal system - diarrhoea, bleeding and abdominal pain.
  • Kidneys - initially no symptoms, although tests can show blood or protein in the urine, or the amount of urine produced may suddenly reduce or stop.

Vasculitis causes

In most cases of vasculitis, the exact cause isn't known – although research suggests there may be a genetic link which increases the risk, and exposure to chemicals in the environment or some types of infection may be a trigger for a susceptible person.

However, this doesn't mean vasculitis can be inherited.

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Diagnosis and treatment of vasculitis

It's crucial to get a diagnosis of vasculitis as early as possible, so the right treatment can be started – as a delay could result in further permanent damage.

Making the right diagnosis depends on the patient's symptoms, and often a combination of blood tests, X-rays, scans and a biopsy.

Most patients will need some treatment – often steroid drugs – to get the disease under control and then keep it in remission. It can be fatal, although only in some cases of severe disease if it's not diagnosed early or treated correctly.

Milder cases may cause damage to organs or discomfort – but aren't life-threatening.

Mills adds: “The key to a successful outcome is early recognition and diagnosis, followed by appropriate and effective drug therapy. This will save lives and preserve quality of life.”

Have you heard of vasculitis? Do you suffer from any of the symptoms? Let us know in the Comments below.