Vasculitis (Leukocytoclastic Vasculitis)

Leukocytoclastic vasculitis, also known as hypersensitivity vasculitis, is an inflammation of blood vessels that forms small lesions on the skin.

The direct cause is unknown, but vasculitis is often linked to autoimmune disorders. It could also be triggered by allergies, medication, or an infection. Inflammatory bowel disease, rheumatoid arthritis, lupus erythematosus, Sjögren syndrome, and less often malignancy are some of the various conditions associated with the vasculitis.

The disease is usually limited to the skin, but it can also affect many different organs of the body such as the kidneys, central nervous system, heart, gastrointestinal tract, and lungs.

The drugs that are most frequently listed as being associated with the development of leukocytoclastic vasculitis include: penicillin, cephalosporin, sulfonamide, some medicines used to control blood pressure (loop and thiazide-type diuretics), phenytoin and allopurinol. Infections that may be associated with leukocytoclastic vasculitisinclude hepatitis B or C virus, chronic infection with bacteria and HIV virus.

Symptoms

It usually appears on the legs and looks like a purple rash or hives. This is because damaged blood vessels leak into small areas and form grouped lesions. These lesions typically appear on the legs. In most cases, the lesions are asymptomatic or are slightly itchy and painful. However, in the case of severe vessel inflammation, large and painful blisters appear. They may also ulcerate.

Fever, muscle aches, weight loss, and joint pain can also be symptoms. Some may also experience blood in the urine or stool, abdominal pain, vomiting, cough, numbness, and weakness if the disease involves other systems.

Some types are long lasting while others only last a short time (1 to 4 weeks). In severe cases, the blood supply to tissues and organs gets cut off, causing damage and even death.

What can I do?

If you have recently started a new medicine and develop a rash or other symptoms, speak to your GP or pharmacist. Drug-induced leukocytoclastic vasculitis is one possible cause, and symptoms may appear within 2 to 10 days after exposure. Do not stop any prescribed medication without consulting a healthcare professional.

In addition:

• Rest and keep your legs elevated if the rash is mainly on your lower limbs.

• Avoid standing for long periods.

• Wear loose-fitting clothing to avoid irritating the affected skin.

• Use gentle skin moisturisers if the area is dry or irritated.

Should I seek medical care?

Yes, you should see a GP if you develop symptoms suggestive of vasculitis, such as a persistent or worsening rash. While leukocytoclastic vasculitis usually affects the skin alone, it can occasionally involve internal organs such as the kidneys or bowels. Early medical assessment is important to rule out any serious underlying cause or systemic involvement.

Seek urgent medical attention if you experience additional symptoms such as:

• Blood in the urine or stools

• Severe abdominal pain

• Breathlessness

• Joint swelling or pain

• Unexplained weight loss or fever

These may indicate more extensive involvement that requires specialist input.

Treatment

A GP or specialist (such as a dermatologist or rheumatologist) can often make a diagnosis by examining the skin lesions. A skin biopsy (such as a punch biopsy) can confirm the diagnosis. However, further investigations are typically needed to check for any associated systemic conditions. These may include:

• Full blood count (FBC)

• Urinalysis

• Kidney and liver function tests

• Rheumatoid factor and antinuclear antibodies

• Hepatitis and HIV screening

• Chest X-ray

Managing Vasculitis

• Corticosteroids are commonly used to reduce inflammation. In mild cases, topical steroids may be sufficient.

• For more severe or systemic vasculitis (affecting internal organs or causing widespread or ulcerating skin lesions), oral or intravenous corticosteroids and immunosuppressive medications (e.g. azathioprine, methotrexate, or cyclophosphamide) may be required.

• If the condition is triggered by a medication, infection, or food allergen, identifying and removing the cause can lead to improvement—often within 2 weeks.

• In some chronic or recurring cases, other treatments such as colchicine or dapsone may be considered under specialist supervision.

Always consult a healthcare professional for appropriate diagnosis and treatment planning.