Urticarial vasculitis is an autoimmune condition that causes itchy or painful hives. Some people may also develop inflammation in other organs, such as the kidneys or lungs.

Vasculitis is a group of autoimmune conditions that cause inflammation in your blood vessels. Over time, this inflammation can lead to blood vessel damage and impaired blood flow.

Urticarial vasculitis is a rare form of vasculitis that causes an outbreak of hives (urticaria) on your skin that lasts longer than 24 hours. When doctors examine these hives under a microscope, they can also see evidence of inflammation in your small blood vessels.

Urticarial vasculitis is estimated to occur in about 1 in 200,000 people per year in the United States.

This article examines urticarial vasculitis in more detail, including symptoms, causes, and treatment options.

People with urticarial vasculitis usually experience episodes of hives that last longer than 24 hours. For most people, hives episodes last longer than 6 weeks.

Hives may appear as bumps or patches that are:

  • swollen
  • raised
  • itchy
  • reddish with a white center on light skin tones
  • slightly lighter, slightly darker, or the same color as dark skin tones

Your hives may also contain red or purple pinpoint spots called petechiae.

Some people develop angioedema, which is swelling in the deep layer of your skin called the dermis. It can give the affected area a puffy appearance.

Once your hives go away, your skin may continue to look discolored.

Potential complications of urticarial vasculitis

Many people with urticarial vasculitis can manage their disease with medications, but some people can develop life threatening complications. In serious cases, some people with urticarial vasculitis may experience complications such as:

Very serious cases may cause problems such as permanent kidney or eye damage.

The cause of urticarial vasculitis isn’t clear. It’s thought to be caused by an autoimmune reaction where your immune system mistakenly attacks healthy cells.

Women and adults between the ages of 30 to 50 seem to be at a higher risk of developing urticarial vasculitis.

Urticarial vasculitis often, but not always, develops after exposure to a certain trigger. If no trigger can be identified, it’s referred to as idiopathic urticarial vasculitis.

Common triggers of urticarial vasculitis include:

  • other autoimmune conditions
  • infections
  • certain medications
  • certain types of cancer

Autoimmune triggers

Sometimes urticarial vasculitis is triggered by other autoimmune diseases such as:

Infection triggers

Infections that have been associated with urticarial vasculitis include:

Medication triggers

Some drugs that have been associated with urticarial vasculitis include:

  • cimetidine (Tagamet)
  • diltiazem (Cardizem and others)
  • potassium iodide
  • fluoxetine (Prozac)
  • nonsteroidal anti-inflammatory drugs (NSAIDs)
  • methotrexate (Trexall and others)
  • telmisartan (Micardis)
  • enalapril (Vasotec and others)
  • levetiracetam (Keppra)
  • some over-the-counter diet pills

Cancer triggers

Urticarial vasculitis can be a complication or symptom of paraneoplastic syndromes. Paraneoplastic syndromes are collections of symptoms that develop due to chemicals secreted by cancer cells.

Types of cancers that have been associated with urticarial vasculitis include:

Doctors use a combination of tests to diagnose urticarial vasculitis. Initial tests you’ll likely receive include:

  • a physical exam
  • a review of your symptoms
  • a review of your personal and family medical histories

If your doctor thinks more testing is necessary, you may receive additional tests such as:

  • blood tests
  • urine tests
  • imaging

The gold standard test for confirming the diagnosis is a skin biopsy, where doctors take a small sample of your skin and examine it under a microscope.

The main treatment for urticarial vasculitis is medications to reduce your immune system activity.

You might receive medications such as:

You may need to try several types of medications before finding one that works and causes limited side effects.

Some ways you may be able to reduce your symptoms and support healing include:

It’s not clear how to best prevent urticarial vasculitis since the underlying cause isn’t known.

Avoiding or reducing contact with your triggers can potentially help reduce the frequency of your outbreaks. For example, taking precautions to avoid illness, like washing your hands regularly, might help reduce your chances of developing a triggering infection.

Urticarial vasculitis is a chronic autoimmune condition. It causes hives on your skin that last more than 24 hours. Symptoms often flare for weeks to months at a time.

Although the exact cause isn’t known, urticarial vasculitis often develops after an identifiable trigger such as an infection.

Many people with urticarial vasculitis can manage their condition with medications to reduce the autoimmune reaction. A doctor can help you develop a treatment plan to keep your symptoms under control.