Leukocytoclastic vasculitis (LCV), also known as hypersensitivity vasculitis, is an inflammatory condition that affects the small blood vessels, particularly in the skin. It is not a disease in itself but rather a response to a range of underlying triggers, including infections, medications, autoimmune disorders, and other systemic conditions. In some instances, the cause remains unidentified. LCV may be limited to the skin, but in some cases, it can involve internal organs.

Underlying Causes of Leukocytoclastic Vasculitis

LCV occurs when immune complexes are deposited in small blood vessels, triggering inflammation and vascular damage. Approximately half of the diagnosed cases do not have a clearly identifiable cause. However, the remaining cases are associated with various factors.

Medication-Induced Cases

Roughly 10% of LCV cases are related to medication use. A hypersensitivity reaction can develop shortly after the introduction of a new drug, an increased dose, or reintroduction after a break. The reaction usually appears within one to three weeks of exposure.

Medications frequently associated with LCV include:

  • Antibiotics (especially sulfonamides, quinolones, and beta-lactams)

  • Immunosuppressive drugs like cyclosporine and azathioprine

  • Chemotherapy agents such as methotrexate

  • Antithyroid drugs (e.g., propylthiouracil)

  • Certain anti-epileptic medications including valproic acid and phenytoin

  • Tumor necrosis factor-alpha inhibitors

  • Blood pressure medications like hydralazine

  • NSAIDs such as ibuprofen, naproxen, and aspirin

LCV Triggered by Other Conditions

In many cases, LCV arises as a result of an underlying health condition that alters immune function. Notable conditions associated with LCV include:

  • Respiratory tract infections

  • Inflammatory bowel disease (Crohn's disease and ulcerative colitis)

  • Autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus

  • Sjögren’s syndrome

  • Certain types of cancer, although less frequently than other triggers

While LCV is usually not life-threatening, the outcome depends on whether there is organ involvement and the nature of any associated diseases. Prognosis is generally favorable, especially in isolated skin-limited cases.

What LCV Looks Like on the Skin

LCV presents with visible skin lesions due to bleeding under the skin from damaged capillaries. These lesions may be scattered or grouped and are commonly found on the lower extremities.

Common characteristics include:

  • Raised purplish or reddish spots that resemble bruises (purpura)

  • Non-blanching spots, which do not fade when pressed

  • Lesions primarily on the legs, trunk, or buttocks, with occasional appearance on the arms and hands

  • Urticaria that persists for more than 24 hours

  • Petechiae (tiny pinpoint dots under the skin)

  • Blistering and ulcerations in severe cases

How LCV Feels to the Patient

The experience of LCV varies by individual. In some people, it causes no discomfort. In others, the rash may lead to sensations such as:

  • Itching

  • Burning

  • Pain

If internal organs are involved, symptoms will depend on the organ affected. These can include:

  • Joint pain or swelling

  • Muscle aches

  • Fever

  • Abdominal pain

  • Vomiting

  • Blood in urine or stool

  • Respiratory symptoms such as cough

  • Neurological issues like numbness or weakness

How LCV Is Diagnosed

The diagnosis of LCV requires careful clinical evaluation, as it can mimic various other conditions. A skin biopsy is considered the most reliable diagnostic method. A sample of skin is typically taken using a punch biopsy tool that collects a small but deep section of tissue for examination. Under a microscope, this sample can reveal the classic signs of inflammation and vessel damage typical of LCV.

To identify possible systemic involvement or an underlying condition, a range of laboratory tests may be performed, including:

  • Complete blood count (CBC)

  • Tests for inflammation such as erythrocyte sedimentation rate (ESR)

  • Antinuclear antibodies (ANA) to check for autoimmune activity

  • Rheumatoid factor

  • Blood chemistry to assess kidney and liver function

  • Antineutrophil cytoplasmic antibodies (ANCA)

  • Complement system levels

  • Hepatitis B and C screening

  • HIV testing

  • Urinalysis to detect kidney abnormalities

Distinguishing LCV from Other Conditions

Several other conditions can produce similar symptoms, especially purpura. To confirm an LCV diagnosis, it’s important to rule out other possibilities such as:

  • Scurvy (vitamin C deficiency)

  • Connective tissue disorders like Ehlers-Danlos syndrome

  • Lymphocytic vasculitis

  • Amyloidosis

  • Clotting disorders including disseminated intravascular coagulation (DIC)

  • Blood clot-related conditions like emboli

  • Bleeding disorders such as von Willebrand disease or thrombocytopenia

  • Skin trauma or chronic venous insufficiency

Can LCV Be Cured?

The outlook for individuals with leukocytoclastic vasculitis is generally good. In many cases, particularly those confined to the skin, the condition resolves spontaneously within several weeks. When the condition is linked to a specific trigger, removing that factor—such as stopping a medication—can lead to rapid improvement.

However, about 10% of individuals may develop chronic or recurrent forms of LCV, especially if it’s related to an ongoing health problem. In such cases, management focuses on treating the underlying condition and controlling flare-ups to maintain remission.

Medications for Managing LCV

The severity of symptoms and presence of systemic involvement influence the choice of treatment. For mild cases confined to the skin, supportive care is usually sufficient. This might include:

  • Antihistamines to reduce itching

  • NSAIDs like ibuprofen or naproxen to manage discomfort

In more serious or persistent cases, systemic therapy may be necessary. Commonly used medications include:

  • Corticosteroids (such as prednisone) to control inflammation

  • Colchicine, often used for recurrent LCV

  • Dapsone, particularly helpful for skin-limited vasculitis

  • Hydroxychloroquine, especially if an autoimmune disease is involved

  • Immunosuppressants like azathioprine or mycophenolate mofetil when internal organs are affected

Treatment should always be personalized based on the patient's symptoms, response to therapy, and overall health.

Self-Care and Lifestyle Tips for Skin-Limited LCV

In mild or skin-limited cases of LCV, home care strategies can support recovery and reduce discomfort:

  • Avoid prolonged periods of standing or walking

  • Elevate the legs while resting to reduce swelling

  • Use compression stockings when appropriate

  • Apply cold compresses to affected areas to soothe irritation

  • Wear comfortable, loose-fitting clothing

Adhering to medical advice and following up with routine check-ups are essential for managing chronic or systemic LCV effectively.

Conclusion

Leukocytoclastic vasculitis is a condition involving inflammation of the skin’s small blood vessels, often presenting as purplish lesions on the legs and other parts of the body. While it can result from medications, infections, or autoimmune conditions, about half of all cases have no clear cause. Most skin-limited cases resolve on their own or with minimal treatment, but systemic involvement requires more intensive care. Prompt diagnosis through biopsy and appropriate testing ensures effective treatment and monitoring, helping most individuals recover and maintain a good quality of life.