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Facts about the skin from DermNet New Zealand Trust. Topic index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Cutaneous vasculitis

What is cutaneous vasculitis?

Cutaneous vasculitis is a term for inflammation of the blood vessels in the skin. The inflammation can affect any of the vessels in the skin including capillaries, venules, arterioles and lymphatics. Cutaneous vasculitis can be due to any of several different causes and can have a wide variety of clinical presentations.

In most cases an underlying cause is not found and the disease is self-limiting. In a minority of patients, cutaneous vasculitis can be part of a more severe vasculitis affecting other organs in the body. This is known as systemic vasculitis.

Cutaneous vasculitis
Ecchymoses & petechiae
Cutaneous vasculitis
Ulceration (systemic sclerosis)
Cutaneous vasculitis
Petechiae
Cutaneous vasculitis
Lymphocytic vasculitis
Cutaneous vasculitis
Hypersensitivity vasculitis (streptococcal)
Cutaneous vasculitis
Bullous leukocytoclastic vasculitis
Cutaneous vasculitis

More images of cutaneous vasculitis ...

How does vasculitis arise?

Many different insults may cause an identical inflammatory response within the blood vessel wall. This inflammation is thought to arise through one or more of three main mechanisms.

Complement refers to a group of proteins in the blood and tissue fluids that attack infection and foreign bodies and can damage the vessel wall.

Vasculitis can be triggered by one or more factors.

Bacterial, viral or other infection

Vasculitis due to infection can occur through any of the above mechanisms. Treatment of the infection can clear the rash. Any virus can be implicated, particularly hepatitis B and C and haemorrhagic fever.

Drugs

Drugs are a common cause of vasculitis particularly when in combination with other precipitants such as infection, malignancy (cancer) or autoimmune disorders. Vasculitis usually clears up when the responsible medication is stopped.

The medications that most frequently cause vasculitis are:

Food

Some foods and food additives (e.g. tartrazine) may cause a vasculitis, but this is uncommon.

Reduced blood flow

Vasculitic reactions are more likely if the blood flow is reduced. For example:

Mediators of inflammation such as antibodies and complement circulate in the bloodstream. If the blood flow is slowed or poor, these mediators are more likely to stick to the vessel wall resulting in vasculitis.

Malignancy

As the body tries to rid itself of cancer, it makes an increased number of antibodies that circulate in the bloodstream. Extra proteins in the blood make it more viscous and increase sludging. These factors may result in vasculitis.

Autoimmune disorders

Diseases such as systemic lupus erythematosus (SLE), dermatomyositis, polyarteritis nodosa (PAN) and rheumatoid arthritis are termed autoimmune disorders because affected patients have antibodies in their bloodstream that target the individual's own tissues. Some of these antibodies can target the blood vessels resulting in vasculitis.

Clinical features of cutaneous vasculitis

Cutaneous vasculitis can be acute, subacute or chronic but in all forms the rash usually presents on the limbs, especially the lower limb.

Vasculitis can have a varied appearance and there is considerable overlap in clinical appearance of the acute, subacute and chronic forms.

Acute vasculitis

Acute vasculitis may be called leukocytoclastic vasculitis because of the finding of broken-up leukocytes (white blood cells) under the microscope, and is also sometimes referred to as allergic or hypersensitivity vasculitis. It presents with bleeding under the skin (purpura). Small spots of bleeding are called petechiae. Large bruises are called ecchymoses. In severe cases the vasculitis impairs the blood flow to such an extent that the overlying skin is deprived of blood flow; it turns black and then ulcerates within a few days. This is called necrosis. Patients may also experience systemic symptoms with fever, joint pains and stomach upsets at any time during an attack. The acute rash usually subsides within 2-3 weeks but may recur.

Subacute vasculitis

Subacute vasculitis tends to start off less dramatically. It usually results in mild purpura in association with wheals, flat red patches and small bumps (macules and papules). It may resemble urticaria, in which case it is called urticarial vasculitis.

Chronic vasculitis

Chronic vasculitis tends to present with macules and papules but purpura and urticaria may be present. Crops of vasculitic spots may keep appearing for many months but the affected patients usually feel quite well.

Special kinds of cutaneous vasculitis

Some variants of cutaneous vasculitis have unique features and will be considered separately.

Large vessel vasculitis

Small vessel vasculitis

How is cutaneous vasculitis diagnosed?

In many cases the diagnosis of vasculitis can be made on the basis of its appearance without requiring any further tests. Sometimes a skin biopsy is performed to confirm the diagnosis but this rarely explains what caused it, as vasculitis is the common endpoint of many different events.

Screening tests are requested in most cases of vasculitis to identify any underlying cause and to determine the extent of involvement of internal organs.

Routine investigations

Patients will usually have blood tests to check liver and kidney function and a urine test looking for protein or bleeding, which could indicate vasculitis in the kidneys.

The following blood tests may also be requested:

If this initial screen indicates an abnormality or if there is clinical suspicion of a more widespread vasculitic process further investigations will be requested. In the majority of patients no underlying cause is found in spite of extensive investigations.

What is the treatment for vasculitis?

In most cases general measures are all that is required to keep the patient comfortable until the rash spontaneously resolves.

If an underlying cause is found, removing the trigger usually clears the rash.

Some patients have a more persistent vasculitis limited to the skin. Medications used to control severe cutaneous vasculitis include:

If cutaneous vasculitis is a manifestation of systemic vasculitis then treatment of the systemic disorder is required.

Will the vasculitis clear up?

Vasculitis limited to the skin has a good prognosis with most cases resolving within a period of weeks to months. The vasculitis may recur at variable intervals after the initial episode.

The prognosis of systemic vasculitis is dependent upon the severity of involvement of other organs. If vasculitis affects the kidneys, lungs or brain it can be life-threatening.

Related information

References:

On DermNet NZ:

Other websites:

Medscape Reference

Author: Dr Amy Stanway, Dermatology Registrar, Health Waikato

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