Allergic vasculitis

Introduction to allergic vasculitis Allergic vasculitis (Allergicvasculitis) is a relatively common disease. Its histopathology has vascular inflammation of white blood cell nuclear rupture, skin damage, and multiple visceral injuries. This disease has many names. To prevent confusion, Ruiter believes This disease is called allergic vasculitis, and this name reflects the inflammatory changes of blood vessels caused by allergies. The disease is of different severity. The lighter lesions can only be recovered in a few weeks. In severe cases, many organs may be damaged or even life-threatening. basic knowledge The proportion of illness: 0.06% Susceptible people: no specific people Mode of infection: non-infectious Complications: abdominal pain, blood in the stool

Causes of allergic vasculitis

Causes

Drug factor

The pathogenesis of this disease is more complicated. It is generally believed that the most common pathogenic drugs are barbiturates, phenothiazines, sulfonamides, penicillins, iodides, aspirin and alloproteins, insecticides, Herbicides and petroleum products are also associated with this disease.

infection

Infection is also an important factor, such as viruses, streptococcus, tuberculosis, leprosy, etc. Fungi and protozoa are also considered to be a causative factor. Bacteria stimulate the blood vessel wall to increase vascular permeability, while attracting neutral polynuclear leukocytes to be accumulated in immunity. The site of deposition of the complex causes inflammatory cell infiltration.

Intrinsic disease

In addition, intrinsic diseases such as frozen proteinemia, hyperglobulinemia, systemic lupus erythematosus, rheumatoid arthritis, etc. can also cause the disease.

Pathogenesis

Most of the factors are not directly pathogenic, only Streptococcus M protein, Mycobacterium tuberculosis, and hepatitis B antigens have been shown to be directly pathogenic. These three antigens always have an antigen in the same way as their corresponding antibodies. The same way in the blood vessels coexists, when protein antigens enter the blood circulation, producing specific antibodies, especially IgG or IgM, which form immune complexes in the bloodstream or in the interstitial space. This complex is deposited in blood vessels. In the wall and surrounding tissues, activated genus C3 produces anaphylatoxins, causing mast cells to release histamine, increasing vascular permeability, and attracting neutral polynuclear leukocytes to accumulate in the immune complex deposition site, causing inflammatory cell infiltration and adhesion. The immune complex on the surface of platelets and neutral polynuclear leukocytes, combined with complement reactivation of complement, causes a complement sequence reaction, causing platelet and neutral polynuclear leukocyte lysis, at which time platelets release coagulation factors and vasoactive substances, causing fibrin Deposition and hemorrhage, when neutral polynuclear leukocytes release collagenase, elastase and other water Enzymes that destroy the collagen fibers, elastic fibers, basement membrane and surrounding tissue, the blood vessel wall infiltration of inflammatory cells, deposition of fibrin blood vessel wall damage and necrosis, vasculitis causes a variety of symptoms.

Allergic vasculitis prevention

The disease is closely related to type III allergy. For some patients with obvious incentives, it should avoid contact with predisposing factors and prevent the cause. Other patients with unclear etiology, in addition to active treatment, need to be strictly screened to find out the cause and take preventive measures.

Allergic skin nodular vasculitis prevention is divided into four aspects:

1. To prevent the disease by the cause of the disease is the main means to prevent this disease.

2. Early diagnosis, early treatment, as far as possible to find the pathogen, to treat the cause.

3. Actively participate in outdoor sports, increase your personal physique and improve your immunity.

4. Regularly participate in the physical examination of the unit or individual organization, and find that the condition is timely to the hospital.

Allergic vasculitis complications Complications, abdominal pain, blood in the stool

67% of patients with this disease may develop pleomorphic skin lesions, but often with palpable plaques, 75% of patients have non-specific fever, about 2/3 of patients have joint pain and joint swelling, lesions can be violated Mucosa, nasal discharge, hemoptysis, blood in the stool, one third of patients with kidney involvement, proteinuria and hematuria, severe renal failure is the main cause of death, abdominal insults, fat cramps, blood in the stool, acute cholecystitis, etc. Gastrointestinal symptoms, may have pancreatitis, diabetes, chest x-ray examination with pneumonia and nodular shadows, pleurisy or pleural effusion, can violate the nervous system, such as headache, diplopia, delusion, insanity, and even Cerebral thrombosis and spasm, difficulty in swallowing, sensory and/or motor dysfunction, etc., heart damage is myocardial infarction, heart rhythm disorder and pericarditis, renal cortical ischemia may produce severe hypertension, the most common eye of systemic vasculitis The manifestations of scleral inflammation and retinal hemorrhage, painful swelling of the epididymis and testis may be a manifestation of vasculitis.

Allergic vasculitis symptoms Common symptoms Abdominal pain, weakness, small vessel fibrosis, hypertension, wheal joint swelling, diplopia

The disease has erythema nodules in the lower limbs, tenderness, and may also be accompanied by purpura, purpuric papules, wheals, pimples and other skin lesions. The pathological manifestations of the skin are inflammatory cell infiltration of the blood vessel wall, mainly polynuclear leukocytes and Fibrin deposition, multinucleated leukocyte infiltration around the blood vessels, accompanied by nuclear dust and red blood cell exudation, according to the above characteristics can be clearly diagnosed, the disease can be divided into two types:

Skin type allergic vasculitis

The disease only affects the skin, mostly in young and middle-aged, generally fatigue, joint muscle pain and other symptoms, a few cases may have irregular fever, but also without the above symptoms, skin damage can be pleomorphic, with erythema, knot Festival, purpura, wheal, blood blisters, papules, necrosis and ulcers, etc., the most common under the knees, with the lower part of the lower leg and the back of the foot, the more lesions begin to be characterized by purpura-like rash, pressed Does not fade, is due to the infiltration and exudation of inflammatory cells in the blood vessel wall, so this ecchymosis is high and can be touched, it is the characteristics of this disease, and some begin with subcutaneous nodules, such as soybeans to broad beans and small Jujube size, light red has tenderness, and some begin to be completely like purplish-like skin lesions. Some skin lesions begin to change like erysipelas, some resemble morphological changes, some resemble polymorphic erythema, and develop in lesions. In the process, it may be accompanied by wheals, pimples, etc. Due to severe inflammatory reaction, blood blister, necrosis and ulceration occur on purpura and purpura rash. Some nodular lesions may also cause ulceration with pain, edema to the ankle and foot. Heavy, in the afternoon Significant, accompanied by two lower limbs, soreness and weakness, there are many lesions of this disease, but almost all have purpura or nodules, pustules can also occur when extraneous leukocytes infiltration into the surrounding tissues, skin lesions can occur in any The parts, such as the back, upper limbs, buttocks, etc., are symmetrically distributed. The skin lesions have conscious pain, itching or burning sensation, some have no symptoms, and there is tenderness. After the skin lesions, there is pigmentation. If there is ulcer, it can be cured. There are atrophic scars, acute lesions, lesions appear in batches, widespread distribution, with calf edema, severe disease, damage to chronic menstruation, repeated episodes lasting for months or years, lesions can be more than 2 to 4 weeks, some Skin lesions merge with each other and expand into a large lesion, which is more common in the knees, elbows and hands, and appears to be persistent erythema.

2. Systemic allergic vasculitis

The disease is affected by multiple organs, and the condition is heavier. Due to the small blood vessels of the organs, especially the posterior venous veins, the diffuse exudation and hemorrhagic lesions are mostly in the organs. The organ involvement is mostly acute, usually Headache, irregular fever, discomfort, fatigue, joint and muscle pain and other symptoms, different durations, different weights, if it is a single exposure to antigen, about 3 to 4 weeks, if repeated exposure to antigen, repeated episodes, duration of disease For months or years, the prognosis of this disease depends on the degree of disease and disease.

67% of patients develop pleomorphic skin lesions, but often with palpable plaques, 75% of patients have non-specific fever, about 2/3 of patients have joint pain and joint swelling, lesions can invade the mucosa, occur Bowel, hemoptysis, blood in the stool, one third of patients with kidney involvement, proteinuria and hematuria, severe renal failure is the main cause of death, abdominal gout, fat sputum, blood in the stool, acute cholecystitis and other gastrointestinal tracts Symptoms, may have pancreatitis, diabetes, chest X-ray examination with pneumonia and nodular shadows, pleurisy or pleural effusion, can violate the nervous system, such as headache, diplopia, delusion, confusion, and even cerebral thrombosis Harmony, difficulty swallowing, sensory and/or motor dysfunction, etc., heart damage is myocardial infarction, heart rhythm disorder and pericarditis, renal cortical ischemia may produce severe hypertension, the most common ocular manifestations of systemic vasculitis are Scleral laminitis and retinal hemorrhage, painful swelling of the epididymis and testis may be a manifestation of vasculitis. Some people believe that the diagnosis of systemic vasculitis for renal biopsy and direct immunofluorescence Experience often can help confirm the diagnosis.

Examination of allergic vasculitis

1, blood biochemical examination

Skin type allergic vasculitis generally has no obvious changes, systemic allergic vasculitis may have anemia, platelets temporarily reduced, leukocytosis, 1/3 of patients with eosinophilia, generally in the range of 0.04 ~ 0.08, a few 0.56, there are proteins and red blood cells in the urine, and occasionally the granular tube type, the BUN can be elevated in severe cases, more than half of the patients can have increased erythrocyte sedimentation rate, total complement and complement C3, C4 can be reduced, IgG, IgA content increases, IgM decreases The changes are consistent with the condition, the liver function of the patient may be abnormal, and the circulating immune complex is positive. The following tests are also meaningful for the disease, such as anti-nuclear antibody, syphilis serum test, anti-chain "O", rheumatoid factor, cold Globulin and HBsAg should also pay attention to potential infections and tumors, and pay attention to the observation of connective tissue diseases.

2, histopathological examination

The change is mainly based on the severity of the lesion, the length of the disease and the condition of the material at that time. Under normal circumstances, there are inflammatory cell infiltration around the dermal capillaries and small blood vessels, and there are many neutrophil infiltration and many scattered nucleus in the formation of neutrophils. The fissure, called the nuclear dust, is accompanied by the infiltration of tissue cells and eosinophils, and the deposition of fibrin bundles with strong eosin staining around the blood vessels. In the sections, due to the deposition of fibrin and the obvious edema, the blood vessels are surrounded. Collagen has a vague appearance, called fibrin-like degeneration, vascular endothelial cells are swollen, such as severe vascular lumen obstruction, inflammatory cells also invade the blood vessel wall, the blood vessel wall is mainly invaded by neutrophils, so that the blood vessel wall does not Clear, at the same time can also have eosinophils, a small number of mononuclear cells, fibrin bundle deposition and vascular necrosis, more red blood cell extravasation is common, the main features of the disease is the perivascular neutrophils Infiltration, with nuclear dust, accompanied by red blood cell exudation, inflammatory cells infiltrated in the upper part of the dermis, and the blood vessel wall also has a neutral white Invasion, vascular obscuration and necrosis, fibrin bundles around the blood vessels and blood vessels, ulcers are caused by vascular necrosis, and sedimentation of hemosiderin can be seen. In chronic cases, erythrocyte extravasation is rare or no.

3, electron microscopy

It can be found that the veins invading the capillaries, especially the blood vessels of 8-30 m in size, the vascular endothelial cells are swollen in the early stage, the fissures and phagocytic cells are active between the endothelial cells, the basement membrane is thickened, and the neutrophils start in the interstitial space of the blood vessels. Heavy platelets condense in the lumen and pass between endothelial cells.

4, direct immunofluorescence examination

It can be found that IgA antibody is found in the vascular basement membrane, IgM and IgG antibodies and complement C3 deposition in the dermis and subcutaneous tissues, and tissue component destruction can be found in the fixed site, which is mainly found in the fibrin-like necrosis area.

Diagnosis and identification of allergic vasculitis

Diagnosis can be based on medical history, clinical symptoms, and laboratory tests.

The disease needs to be identified with the following diseases:

(1) allergic purpura: mostly occurs in children and adolescents, mostly in the lower extremities with ecchymosis, the most common lesions, can be associated with joint pain, normal platelets, urine can have proteinuria and hematuria, sometimes Occasionally, symptoms of gastrointestinal bleeding.

(2) papular necrotizing tuberculosis rash: more common in young women, near the joints of the limbs or hips, scattered central necrotic solid papules, leaving atrophic scars after the recovery, tuberculin test is strongly positive, histopathology has tuberculosis tissue performance .

(3) skin-type nodular polyarteritis: mostly in the lower limbs, there are subcutaneous nodules distributed along the small arteries, conscious pain and obvious tenderness, skin histopathological manifestations of arteritis and small arterial necrosis.

(4) should also be differentiated from hyperglobulinemia, acute acne-like lichen-like pityriasis and nodular vasculitis.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.