Vasculitis on the Legs: Symptoms, Rash and Signs of Skin Involvement

An unusual rash on the legs that resembles small bruises often prompts people to look up the word "vasculitis." It is impossible to distinguish vascular inflammation from another skin reaction from a photo: this is determined by a doctor based on the skin picture and general condition.

What cutaneous vasculitis is

Vasculitis is an umbrella term for a group of conditions in which the immune system mistakenly attacks blood vessels. They swell and narrow, allow blood through less well, and sometimes stretch and bulge — an aneurysm, whose rupture is dangerous because of internal bleeding.

Cutaneous vasculitis is inflammation primarily of the skin vessels. The classification distinguishes cutaneous leukocytoclastic angiitis and cutaneous arteritis — forms confined to the skin. Vasculitides are divided into primary, when inflammation begins in the vessels themselves, and secondary — a vascular reaction to another disease.

The cause is more often unknown: a combination of hereditary predisposition with environmental factors and infections, including Staphylococcus aureus and hepatitis viruses, is discussed; secondary vasculitis may be a reaction to an infection, another disease or a medication.

What vasculitis on the legs looks like

In the sources, eruptions in vasculitis are described predominantly on the skin of the limbs: hemorrhagic or ulcerative-hemorrhagic, less often — livedo reticularis and skin necrosis. In microscopic polyangiitis, the skin is involved in 70% of patients; in granulomatosis with polyangiitis — in 25–35%.

In immunoglobulin A vasculitis, Schönlein–Henoch disease, the rash looks like small bruises or red-purple spots; on tanned and dark skin they are harder to notice. The form is more common in children, often resolves without treatment, but may affect the kidneys and intestines.

The skin is not the only target. Common symptoms of the group are fever, swelling and a feeling of being unwell; in systemic forms, joint and muscle pain, weakness, numbness and tingling in the limbs are added to the rash.

Rash in vasculitis: types and features

One word describes several different pictures. The sources mention hemorrhagic or ulcerative-hemorrhagic eruptions, livedo reticularis, skin necrosis, small bruises or red-purple spots. When you describe the rash to a doctor, it is useful to note:

• where the first elements appeared and in what order they spread;
• the color and size of the spots;
• whether there is itching and how the rash changed over a day and over a week;
• fever, joint and abdominal pain, the color of urine and stool;
• recent infections and medications taken.

Vasculitis on the hands and in the nose

In the sources, eruptions are described predominantly on the skin of the limbs. Buerger's disease affects the vessels of the legs and arms and reduces blood flow in the hands and feet; in Takayasu arteritis, the limbs may be painful, numb or cold.

Nasal involvement is described in granulomatosis with polyangiitis: more than 90% of patients develop necrotizing inflammation of the upper respiratory tract — ulcerative-necrotizing rhinitis, sinusitis, bleeding and crusts in the nose, and a complication is perforation of the nasal septum with saddle-nose deformity. In children with Kawasaki disease — fever for 5 days or more, rash, red eyes, dry and cracked lips, enlarged lymph nodes in the neck, red fingers or feet.

Temporal pain in people over 50 is a reason not to wait: in giant cell arteritis, inflammation of the temporal arteries causes double vision or vision loss, and without prompt treatment blindness and stroke are possible.

Which examinations help confirm the diagnosis

The diagnosis is made based on the combination of the skin picture, general condition and examination results. The list of tests for vasculitides includes testing for antineutrophil cytoplasmic antibodies (ANCA), C-reactive protein, erythrocyte sedimentation rate, CT angiography and MR angiography; the doctor assesses whether the kidneys are involved — for example, blood in the urine may indicate this.

The doctor assesses not only the rash but also the vessels, kidneys, lungs, nerves, vision and hearing.

When to see a doctor

You should see a doctor if the rash persists, is accompanied by fever, joint and abdominal pain, blood in the urine or stool.

103 or 112 — for sudden vision loss (especially in a person over 50: in temporal arteritis blindness and stroke are possible) or hemoptysis with increasing shortness of breath.

This material is for reference: it helps prepare questions for a doctor but does not replace a consultation — a persistent rash is dealt with by a specialist, not an article.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer