Vasculitis.
Vasculitis is a family of diseases defined by inflammation of blood vessels. Classification depends on vessel size: large (giant cell arteritis, Takayasu's), medium (polyarteritis nodosa, Kawasaki), or small (ANCA-associated vasculitis, IgA vasculitis, cryoglobulinemic vasculitis). Treatment varies dramatically by type — but most vasculitis is highly treatable when caught early. Giant cell arteritis is a medical emergency. ANCA vasculitis is curable in many cases. The diagnosis lives in the antibody panel and the biopsy.
The mechanism, vessel size determines everything.
Vasculitis isn't one disease — it's many. The mechanism, presentation, and treatment depend on which vessels are affected:
Large-vessel vasculitis
Giant cell arteritis (GCA) and Takayasu's arteritis. GCA presents with headache, jaw claudication, scalp tenderness, and vision changes in patients over 50. Vision loss is permanent if untreated — this is a medical emergency.
Medium-vessel vasculitis
Polyarteritis nodosa (PAN) and Kawasaki disease. PAN affects renal and visceral arteries, often associated with hepatitis B. Kawasaki is primarily a pediatric disease with coronary artery aneurysm risk.
ANCA-associated vasculitis
Granulomatosis with polyangiitis (GPA, formerly Wegener's), microscopic polyangiitis (MPA), and eosinophilic GPA (EGPA, formerly Churg-Strauss). PR3-ANCA or MPO-ANCA define them. Affect kidney, lung, sinuses, nerves. Curable with rituximab or cyclophosphamide induction.
Immune complex vasculitis
IgA vasculitis (formerly Henoch-Schönlein), cryoglobulinemic vasculitis (often hepatitis C-driven), hypersensitivity vasculitis. Typically affect skin, kidney, and joints.
The 4-step plan, applied to Vasculitis.
Get the right diagnosis
ANCA panel (PR3, MPO), ANA, hepatitis B and C serology, cryoglobulins, complement (C3, C4), urinalysis with microscopy, ESR/CRP, and imaging or biopsy targeted to the affected vessel. Temporal artery ultrasound or biopsy for suspected GCA. CTA or MRA for large-vessel disease. Renal biopsy for ANCA vasculitis with renal involvement.
Learn more about labs →Clean up your food
Anti-inflammatory Mediterranean pattern. Mind sodium and fluid status with renal involvement. Adequate protein during steroid courses.
Vasculitis & diet →Detox your daily life
Silica exposure is a well-established trigger for ANCA vasculitis. Hepatitis B should be screened for in PAN; hepatitis C in cryoglobulinemic vasculitis. Smoking cessation is critical.
Vasculitis & environment →Build a stronger body
Gentle exercise once disease is controlled. Cardiopulmonary rehabilitation for patients with lung involvement (GPA, EGPA). Resistance training preserves muscle during long steroid courses.
Vasculitis & exercise →
Go deeper.
Common misconceptions.
"Vasculitis is rare and doesn't apply to me."
Some vasculitides are rare. But giant cell arteritis affects 1 in 500 people over 50 — it's the most common vasculitis in older adults. ANCA-associated vasculitis has an incidence of about 20 per million per year. They're not common, but they're not invisible either — and missing them costs vision, kidneys, and lives.
"All vasculitis is fatal without aggressive treatment."
Modern treatment has transformed outcomes. Rituximab-based induction in ANCA vasculitis achieves remission in 75–90% of patients. GCA responds to steroids and tocilizumab. Survival in well-treated GPA and MPA is now measured in decades. The era of universally fatal vasculitis is over.
"If my ANCA is negative, I don't have vasculitis."
ANCA-negative ANCA vasculitis exists (about 10–20% of clinically classic AAV is ANCA-negative). EGPA is ANCA-positive in only about 40% of cases. Clinical features, biopsy, and imaging matter as much as serology. A negative ANCA does not rule out vasculitis.
When to see a rheumatologist.
See a rheumatologist if you have:
- New headache in someone over 50, especially with jaw claudication or vision changes
- Hematuria with elevated creatinine, especially with respiratory symptoms
- Recurrent sinusitis, nasal crusting, or saddle-nose deformity
- Mononeuritis multiplex (multiple peripheral nerves affected)
- Palpable purpura on the legs
- Unexplained constitutional symptoms (fever, weight loss, fatigue) plus organ-specific findings
- Asthma plus eosinophilia plus systemic symptoms (suggestive of EGPA)
Vasculitis is a 'great mimicker' — symptoms can suggest infection, malignancy, or other autoimmune disease. Persistent unexplained symptoms with elevated inflammatory markers deserve rheumatology evaluation.
- Jennette JC, et al. 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides. Arthritis Rheum, 2013. PubMed 23045170
- Stone JH, et al. Trial of tocilizumab in giant cell arteritis (GiACTA). N Engl J Med, 2017. PubMed 28745999
- Stone JH, et al. Rituximab vs cyclophosphamide for ANCA-associated vasculitis (RAVE). N Engl J Med, 2010. PubMed 20647199
- Wechsler ME, et al. Mepolizumab for EGPA. N Engl J Med, 2017.