What types of vasculitis are there?
Vasculitis is classified according to the caliber of the vessels predominantly affected. Large vessels are affected by Takayasu's arteritis and giant cell arteritis - the latter is typical for people over 50 years of age and is dangerous for vision loss. The middle arteries are affected by polyarteritis nodosa and Kawasaki disease in children. Small vessels are involved in ANCA-associated vasculitis and in immune complex forms, including hemorrhagic vasculitis. There are also secondary vasculitis - due to infections, tumors, rheumatic diseases or taking medications.
- Large vessels: giant cell arteritis, Takayasu arteritis
- Moderate: polyarteritis nodosa, Kawasaki disease
- Minor: ANCA-associated vasculitis
- Immune complex: Henoch-Schönlein purpura, cryoglobulinemic
- Secondary vasculitis in infections and other diseases
Causes and mechanism
The exact cause of most vasculitis is unknown. It is believed that in a predisposed person, a previous infection, taking certain medications, or another external factor triggers a failure of the immune response. Immune cells and antibodies begin to damage the endothelium, the inner lining of the vessel. Inflammation develops, the wall thickens, the lumen narrows, blood clots form, or, conversely, the wall becomes thinner with the formation of an aneurysm. Some forms are closely associated with viral hepatitis; smoking increases the risk of certain variants.
- Genetic predisposition
- Past bacterial and viral infections
- Chronic viral hepatitis
- Reaction to drugs
- Smoking
- Concomitant autoimmune diseases
Symptoms
The onset is often nonspecific and resembles a protracted infection: fever, weakness, night sweats, weight loss, muscle and joint pain. Then signs of damage to specific organs appear. Purpura, nodules, and ulcers appear on the skin; if the kidneys are involved - blood and protein in the urine, swelling, increased pressure. Damage to the lungs results in coughing and hemoptysis, and damage to the nerves results in numbness and weakness in the hand or foot. Giant cell arteritis is characterized by headache in the temples and blurred vision.
- Prolonged fever and weight loss
- Purpuric rash, nodules, skin ulcers
- Joint and muscle pain
- Blood and protein in the urine, swelling
- Cough, shortness of breath, hemoptysis
- Numbness and weakness in the limbs
- Headache, jaw pain when chewing, blurred vision
Diagnostics
There is no specific test for vasculitis; the diagnosis is made from a combination of data. The initial examination includes a complete blood count with ESR, C-reactive protein, urinalysis, assessment of kidney and liver function. Determining ANCA is key, as is ruling out infections and other autoimmune diseases. The confirmatory method remains a biopsy of the affected organ. To assess large vessels, ultrasound, CT and MR angiography are used, and in case of lung damage, computed tomography is used.
- Complete blood count and ESR
- C-reactive protein
- Urinalysis, creatinine
- ANCA, antinuclear antibodies
- Markers of viral hepatitis
- Biopsy of skin, kidney or other organ
- CT chest, vascular angiography
Treatment and observation
Therapy is divided into two stages: induction of remission and its maintenance. In the acute period, glucocorticoids are usually prescribed in combination with immunosuppressive drugs; in severe forms, genetic engineering therapy and plasma exchange are used. Then the doses are gradually reduced and maintenance treatment is started, which can last for years. All medications are prescribed and monitored by a rheumatologist: they are effective, but require regular tests and infection prevention. Self-cancellation of treatment is a common cause of severe exacerbations.
- Glucocorticoids during exacerbation
- Immunosuppressive drugs
- Genetic engineering biological therapy for severe forms
- Plasma exchange according to indications
- Regular monitoring of blood and urine tests
- Vaccination and infection prevention according to the doctor’s plan
- Stop smoking, control blood pressure and cholesterol levels