What Are the Causes of Vasculitis?

Vasculitis is the infiltration of inflammatory cells in the vascular wall and surrounding blood vessels, accompanied by vascular damage, including cellulose deposition, collagen fibrosis, endothelial cells and muscle cell necrosis. Pathogenic factors that directly affect the vascular wall are primary vasculitis, and those who produce certain clinical symptoms and signs based on vascular inflammation are vasculitis diseases; those with inflammatory lesions in adjacent tissues that spread to the vascular wall are secondary blood vessels. inflammation.

Basic Information

nickname: Vasculitis
English name: vasculitis
Visiting department: Vascular surgery
Common causes: Serum diseases, drug reactions, infections, and hepatitis B virus, cytomegalovirus, and herpes simplex virus infections

Common symptoms: Fever, fatigue, joint muscle pain, raised purpura, nodular necrotic rash, etc.
Contagious: no

Causes of vasculitis

A few causes are more definite, such as serum sickness, drug allergy and infection. Hepatitis B virus has been proven to be the cause of a variety of vasculitis; Chinese cytomegalovirus, herpes simplex virus, etc. can cause vasculitis.

Vasculitis classification

1. Allergic leukocyte fragmentation (necrotizing) vasculitis

A group of vasculitis diseases caused by a variety of causes of allergies, mainly involving small blood vessels, especially the retrocapillary veins. It is characterized by fibrin deposition, degeneration and necrosis in the tube wall and surrounding tissues, large infiltration of neutrophils and fragmentation of nuclei into nuclear dust. Onset is more acute, often with different forms of skin damage. There are mainly allergic skin vasculitis, allergic systemic vasculitis, allergic purpura, low complement (urticaria-like) vasculitis and so on.

2. Nodular polyarteritis

A non-granulomatous vasculitis characterized by segmental inflammation and necrosis of the middle and small muscle arteries. It can involve all tissues, organs and blood vessels of the whole body. The clinical manifestations are complicated and non-specific. There are mainly systemic nodular polyarteritis, benign skin nodular polyarteritis, and infant nodular polyarteritis.

3. Thrombotic vasculitis

It mainly involves the middle and small arteries and veins, is characterized by thrombosis in the vascular cavity, and presents different clinical manifestations. There are mainly thrombo-occlusive vasculitis, thrombophlebitis, malignant atrophic papules, reticuloplaque vasculitis, and thrombotic thrombocytopenic purpura.

4. Granulomatous vasculitis

It is a multi-system disease involving large, medium and small blood vessels. It is characterized by the formation of granulomas inside and outside the wall of the tube. The course is slow and sometimes severe. There are mainly Wegener's granulomas, allergic granulomatous vasculitis, temporal arteritis, and aortic arteritis.

5. Lymphocytic vasculitis

It is characterized by the involvement of small blood vessels in the skin and infiltration of lymphocytes in the tube wall and surrounding tissues, resulting in different types of skin damage, a slow course and recurrent attacks. There are mainly lymphoma-like papules, acute acne-like lichen psoriasis, and so on.

6. Nodular vasculitis

A group of skin diseases characterized by vascular involvement and subcutaneous nodule damage within the subcutaneous adipose tissue space. There are nodular vasculitis and hard erythema.

7. Blood component abnormal vasculitis

Small blood vessel inflammatory diseases caused by abnormalities in some components of the blood show skin or internal organ damage, and the course is chronic. There are mainly cold globulinemia, cold hyperglobulinemia, and macroglobulinemia.

Clinical manifestations of vasculitis

Main performance

multisystem damage; active glomerulonephritis; ischemic or congestive symptoms and signs, especially seen in young people; raised purpura and other nodular necrotizing rashes; multiple mononeuritis and unknown Cause of fever.

2. Skin type allergic vasculitis

Generally have symptoms such as fatigue, joint muscle pain, and a few cases may have irregular fever. Skin damage can be pleomorphic, including erythema, nodules, purpura, wind mass, blood blister, pimples, necrosis and ulcers. Below the knee is the most common, and the lower calf and the back of the foot have the most skin damage. More skin lesions are initially characterized by purpuric maculopapular rash, which does not fade, so this kind of bruising is higher than the skin can touch, which is the characteristic manifestation of this disease. The edema is heavy in the ankle and the back of the foot, which is more pronounced in the afternoon, and is accompanied by weakness in the lower extremities.

3. Systemic allergic vasculitis

Most are acute onset, usually with headache, irregular fever, discomfort, fatigue, joint and muscle pain and other symptoms. The course of disease is different and the severity is different. If it is exposed to the antigen once, it will heal for 3 to 4 weeks. If it is repeatedly exposed to the antigen repeatedly, the disease will recur. The course of disease will last for months or years. Lesions can invade the mucous membranes and cause nosebleeds and hemoptysis. Renal involvement has proteinuria and hematuria, and severe renal failure is the main cause of death. Intestinal invasion may have gastrointestinal symptoms such as abdominal pain, fatty palate, blood in the stool, and acute cholecystitis.

A chest X-ray showed signs of pneumonia and nodular shadows, pleurisy, or pleural effusion. It can invade the nervous system, such as headache, diplopia, delusion, insanity, and even cerebral thrombosis and paralysis, difficulty in swallowing, and sensory and / or motor dysfunction. Heart damage includes myocardial infarction, heart rhythm disorders, and pericarditis. Renal cortex ischemia can produce severe hypertension. The most common ocular manifestations of systemic vasculitis are episcleritis and retinal hemorrhage. The painful swelling of the epididymis and testicles may be a manifestation of vasculitis.

Vasculitis examination

Routine hematuria, platelet count and blood suspected time, erythrocyte sedimentation, immunoglobulins, circulating immune complexes, C2, C3 and C4, CH50 rheumatoid factor, antinuclear factor, protein electrophoresis, fibrinogen measurement and HBsHg test, etc. Angiography, Doppler ultrasound, and X-ray confirmation should be performed as needed.

Vasculitis diagnosis

The cutaneous vasculitis pathological changes have obvious characteristics, but it is difficult to make accurate clinical diagnosis without combining with clinical manifestations. The main signs of vascular endothelial cell damage are: (1) Circulating endothelial cells (CEC): It is considered to be the only marker and indicator that can specifically and directly reflect vascular endothelial cell damage in the body. (2) coagulation factor (F ): its increased activity is helpful for the identification of necrotizing vasculitis and small vessel disease in large and medium vessels. It is related to the activity of the disease. Nodular polyarteritis, Wegener's granulomatosis and other systemic vasculitis can increase several times when it is effective, and can decrease when the treatment is effective. (3) vW factor (vWF): Plasma vWF levels in patients with cutaneous vasculitis increase significantly, but there is no significant relationship with the severity of vasculitis. (4) Anti-neutrophil cytoplasmic antibody (ANCA) has higher sensitivity and specificity in the diagnosis of Wegener's granulomatosis, multiple arteritis, and some necrotizing vasculitis. It has been confirmed that ANCA is a group of autoantibodies against neutrophil cytoplasmic antigen, which has obvious specificity for Wegener's granulomatosis, and ANCA is considered to be a serological marker of the above diseases. (5) AECA (anti-vascular endothelial cell antibody): It is more common in Wegener's granulomatosis, nodular polyarteritis, micropolyarteritis, and temporal arteritis. The AECA-positive secondary vasculitis includes SLE, RA and Necrotizing Vasculitis with Overlap Syndrome.

Vasculitis treatment

1. Remove the cause and eliminate allergens.

2. Treatment of basic diseases, such as connective tissue disease, tumors.

3. Vasculitis confined to the skin, commonly used antihistamines such as chlorpheniramine, nonsteroidal anti-inflammatory drugs indomethacin (indomethacin), ibuprofen.

4. Systemic vasculitis can be prednisone or cyclophosphamide.

5. Antiplatelet aggregating agents can be used aspirin, vasodilator medicated nifedipine or isosorbide nitrate (as analgesic).