Vasculitis: Understanding Autoimmune Inflammation of Blood Vessels

When your immune system turns against your own blood vessels, things go wrong fast. Vasculitis isn’t just a rash or a sore joint-it’s your body attacking the very pathways that carry oxygen and nutrients to your organs. This isn’t a one-size-fits-all condition. It’s a group of rare but serious autoimmune disorders where inflammation tears through arteries and capillaries, sometimes silently, sometimes violently. Left unchecked, it can block blood flow to your kidneys, lungs, brain, or skin-leading to tissue death, aneurysms, or organ failure.

How Vasculitis Starts: The Immune System’s Mistake

Your immune system is designed to protect you. It recognizes invaders like bacteria and viruses and destroys them. But in vasculitis, something goes haywire. It starts seeing your blood vessel walls as foreign. White blood cells swarm in, releasing chemicals that inflame, weaken, and damage the vessel lining. The result? Narrowed vessels, clots, ruptures, or bulges called aneurysms.

This isn’t random. It’s autoimmune. And it doesn’t pick who it targets. It can strike anyone, but certain types favor specific age groups. Giant cell arteritis, for example, almost always affects people over 50. Kawasaki disease, on the other hand, mostly hits kids under five. The trigger? No one knows for sure. Genetics, infections, or environmental factors may play a role-but the immune system is the real culprit.

Types of Vasculitis: Size Matters

Doctors classify vasculitis by the size of the blood vessels it hits. That tells them what organs are at risk and how aggressive the treatment needs to be.

• Large-vessel vasculitis affects the aorta and its biggest branches. Giant cell arteritis attacks the temporal arteries-those near your temples. If untreated, it can cause blindness or stroke. Takayasu arteritis often shows up in younger women and can narrow arteries leading to the arms, brain, or kidneys.
• Medium-vessel vasculitis targets medium-sized arteries. Polyarteritis nodosa hits muscles, nerves, kidneys, and the gut. Kawasaki disease causes fever, swollen lymph nodes, and red eyes in children-and can lead to coronary artery aneurysms in 20-25% of untreated cases.
• Small-vessel vasculitis is the most common and dangerous. This includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). These are often linked to ANCA antibodies-autoantibodies that attack white blood cells and trigger vessel inflammation. MPA loves the kidneys and lungs. GPA can destroy nasal cartilage and cause lung nodules. EGPA comes with asthma and high eosinophil counts.

Then there’s Buerger’s disease, tied directly to smoking. It blocks small arteries and veins in hands and feet. Stop smoking? The disease may halt. Keep smoking? Amputation becomes likely.

What Symptoms to Watch For

Vasculitis doesn’t scream. It whispers. That’s why it’s often missed for months-or even years.

Common signs include:

• Purple or red spots, bumps, or bruises on the skin
• Joint pain or swelling
• Unexplained fever, weight loss, or night sweats
• Numbness, tingling, or weakness in limbs
• Shortness of breath or coughing up blood
• Stomach pain, diarrhea, or bloody stools
• Headaches, jaw pain when chewing (classic for giant cell arteritis)
• Eye redness, pain, or sudden vision loss

Here’s the catch: these symptoms look like the flu, arthritis, or even allergies. That’s why diagnosis is delayed-on average, 6 to 12 months. By then, damage may already be done.

How Doctors Diagnose Vasculitis

No single test confirms vasculitis. It’s a puzzle. Doctors piece it together using:

• Blood tests: ESR and CRP levels spike when inflammation is active. ANCA testing is key-c-ANCA (targeting proteinase-3) is 80-90% specific for GPA.
• Urine tests: Protein or blood in urine means kidneys are involved. This is critical-even if you feel fine.
• Imaging: CT scans, MRIs, or angiograms show narrowed or blocked vessels. PET scans can detect inflammation in large arteries.
• Biopsy: The gold standard. A small sample of affected tissue (skin, kidney, lung, or temporal artery) shows immune cells tearing through vessel walls. Leukocytoclastic vasculitis-nuclear debris around vessels-is a telltale sign in skin biopsies.

The Five Factor Score helps predict outcomes in polyarteritis nodosa. It looks for: kidney failure, gastrointestinal involvement, heart problems, nerve damage, or central nervous system issues. More factors = higher risk of death.

Treatment: Stopping the Attack

The goal? Stop the immune system from attacking-and protect your organs before it’s too late.

For severe cases, treatment starts with high-dose prednisone (0.5-1 mg per kg daily). That’s often combined with cyclophosphamide or rituximab to knock down the immune response. This phase lasts 3-6 months-called induction.

Then comes maintenance: lower doses of methotrexate, azathioprine, or continued rituximab for 18-24 months. The aim? Keep the disease in remission without wrecking your body with steroids.

Recent breakthroughs have changed the game:

• Avacopan (approved by the FDA in 2021) blocks a key inflammation signal (C5a). In the ADVOCATE trial, patients on avacopan had 2,000 mg less cumulative steroid exposure over a year-without losing effectiveness.
• Tocilizumab (an IL-6 inhibitor) is now approved as an add-on for giant cell arteritis. It helps reduce steroid doses and relapses.
• Mepolizumab is showing promise for EGPA, cutting relapse rates by half in early trials.

For Buerger’s disease? There’s no drug that works. Only one thing does: quit smoking. Completely. No exceptions.

Prognosis: Can You Live With It?

With early treatment, 80-90% of people with ANCA-associated vasculitis reach remission. But here’s the hard truth: about half will relapse within five years. That’s why lifelong monitoring is non-negotiable.

Survival rates depend on organ damage. For polyarteritis nodosa:

• No major organ involvement? 95% survive five years.
• One major factor (kidney, heart, gut)? 75%.
• Two or more? Drops to 50%.

Untreated giant cell arteritis can cause permanent blindness. Untreated Kawasaki disease can lead to heart attacks in children. Vasculitis doesn’t wait. It doesn’t ask permission.

Living With Vasculitis

Most people can manage the disease-but it’s not easy. Medications weaken your immune system, so infections are a constant threat. Steroids cause weight gain, bone loss, and mood swings. You’ll need regular blood tests, imaging, and doctor visits.

Patients often report fatigue, joint pain, and anxiety. Support groups, physical therapy, and mental health care are as important as medication. Stay active. Eat well. Avoid smoking and excessive alcohol. And never skip your follow-ups-even if you feel fine.

Research is moving fast. Scientists are studying biomarkers like BAFF and MCP-1 to predict flares before symptoms start. The goal? Personalized treatment. No more guessing. Just precision.

When to See a Doctor

If you have unexplained symptoms lasting more than two weeks-especially if you’re over 50 and have headaches or jaw pain, or you’re a child with persistent fever and red eyes-see a doctor. Ask specifically about vasculitis. Don’t let it be dismissed as "just stress" or "a virus."

A rheumatologist is your best bet. They’re trained to spot these subtle, systemic diseases. Early diagnosis isn’t just helpful-it’s life-saving.