allergic cutaneous nodular vasculitis
Introduction
Introduction to allergic skin nodular vasculitis Allergic skin nodular vasculitis is mainly a skin disease in which subcutaneous vasculitis in the subcutaneous tissue of the lower limb is a pathological basis to form nodular lesions. This disease occurs mostly in young and middle-aged women. The ratio of male to female is about 1:5, and the average age of onset is 30 years old. The onset has obvious seasonality, most of which is the onset of late spring and early summer. It is heavier in midsummer. After autumn, it relieves the winter regression or residual nodular damage without obvious symptoms. It relapses the following year. basic knowledge The proportion of illness: 0.0006% Susceptible people: no specific people Mode of infection: non-infectious Complications: varicose veins
Cause
Causes of allergic skin nodular vasculitis
(1) Causes of the disease
The etiology of this disease is unknown. Some patients have a clear history of tuberculosis or static tuberculosis. The tuberculin skin test can be strongly positive. The anti-tuberculosis drug treatment has a good effect, suggesting that tuberculosis allergy may be one of the pathogenic factors of this disease; A small number of patients have fever, sore throat or tonsillitis, and anti-"O" rises a few days before and after onset, so their onset may be related to allergy to streptococcal infection; but most cases fail to find factors related to the disease.
(two) pathogenesis
Vasculitis is the main lesion, and the vascular plexus around the skin attachment is often involved. The infiltrating cells are mainly lymphocytes, the PAS staining is negative, and the immunoglobulin is normal. Therefore, the occurrence of this disease may be caused by various factors, and A cutaneous vasculitis disease characterized by delayed type hypersensitivity.
The lesions are mainly in the reticular reticular layer to the subcutaneous fat lobules and their compartments, mainly vascular lesions, accompanied by granulomatous or granulomatous nodules and tissue necrosis.
Vasculitis
The main factors are capillaries and blood vessels, a small number of small arteries and veins and their nourishing blood vessels, and almost all of the capillary plexus around the sweat glands, the lesions are segmental distribution, capillaries and blood vessels, especially veins, the wall Edema, a little eosinophilic substance deposition caused by blurred wall structure, prominent endothelial cell hypertrophy and hyperplasia, lighter nuclear distance shortened to nuclear overlapping, or oval and round, protruding into the cavity, significant There are stenosis or occlusion of the lumen. From the longitudinal section, the endothelial cells are arranged in a cord shape, and the cross-sectional view is the endothelial cell mass. The nourishing vascular lesions are similar to the capillaries and venules. The endothelial cells of the small veins are lighter than the fine veins. The wall muscle bundle is separated by edema and sometimes dispersed into lamellae; the arteriolar ring muscle is increased in tension due to edema, and the arrangement is closely arranged like a tree wheel, while the endothelial cell lesions are lighter, occasionally small arteries and venules. Intracavitary thrombosis and recanalization, lymphatic infiltration in the wall of the tube, no neutrophils and their fragmentation nucleus.
Granuloma and granulomatous nodules
In the fat lobules, a small number of granulomatous nodules of varying size formed by tissue cells, many with multi-nuclear giant cells of varying numbers; most of them are faintly visible capillary or vascular contours in the center of the nodules, due to proliferating endothelium The cells aggregated into a mass, the lumen disappeared, and it was difficult to see the red blood cells. The reticular fiber staining showed the contour of the blood vessels in the nodules. The staining of UEA and F8 showed that the central part of the nodules were endothelial cells, and the Lys and 1-AT staining showed that the periphery of the nodules was tissue. The cells, the former is a true granuloma, while the latter is a granulomatous nodule, with lymphocytes mixed in both nodules, no epithelial-like cells and Langerhans giant cells.
Tissue necrosis
There is a mild inflammatory reaction in the fat lobules, a few fat cells are denatured, and then dissolved to destroy the cavities of different sizes; most of them are necrotic foci of different sizes, the structure is blurred, and then necrosis becomes a red pigmented fine particulate matter. The vascular contours are still faintly visible, the margins of large necrotic lesions are fine, the vein wall is partially or completely necrotic and ruptured, and there are more red blood cells in the necrotic foci, lymphocytes and neutrophils of varying numbers and Its fragmented nuclear dust, occasionally a little eosinophils, small interlobular connective tissue for general inflammation, dermal papilla and epidermis are normal.
Prevention
Allergic skin nodular vasculitis prevention
prevention:
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.
Complication
Allergic skin nodular vasculitis complications Complications varicose veins
Reticular leukoplakia and varicose veins are complications.
Reticular leukoplakia is a vascular disorder of the skin that is caused by a variety of causes. A persistent cyanotic network change in the skin is a clinical feature. When the long-lasting functional vascular changes develop into organic lesions, it is called reticular plaque vasculitis, and the disease is rare in clinical practice. This disease belongs to the category of "blood stasis syndrome" of traditional Chinese medicine. Some people think that this disease is a "catch".
Varicose veins refer to varicose veins and dilatation caused by blood stasis, weak vein wall and other factors. The veins of various parts of the body can be varicose. For example, acne is actually a kind of varicose veins, and clinically visible esophageal varices, varicocele and abdominal varicose veins. The most common site of varicose veins is in the lower extremities. It is worth emphasizing that varicose veins themselves may be secondary manifestations of other lesions, such as venous occlusion, and should be actively treated for primary disease.
Symptom
Allergic skin nodular vasculitis symptoms common symptoms varicose hyperthermia subcutaneous nodules reticular leukoplakia loss of appetite low heat chill
The damage is first seen in the two calves, especially the lower 2/3 of the calf. It is scattered and distributed, not limited to the extension or flexion. It gradually affects the thigh and buttocks during repeated episodes, occasionally involving the forearm, with both sides of the lower thigh For more patients, local pain and tenderness are felt first, and then the subcutaneous nodules are often touched. The number is often less than 10. When other parts are involved, not only the number of lesions increases, but also the lesions are slightly different due to different parts. Broad bean to bayberry size, edge accessible, medium hardness, less initial damage and deeper position, so it is mostly skin color, or light red to bright red, with the duration extended, red can be deepened, in 3 to 4 weeks Inside, the red color retreats, the residual pigmentation spots remain, and the nodule damage completely subsides later, there is a comparative characteristic damage, which lasts longer, is slightly larger than the aforementioned damage, and is purple or dark red. The central skin is smooth and shiny, even desquamation, or has a soft feeling, but never collapses, there is no skin shrinkage and depression after absorption, the hip and thigh damage position is deep, generally hard, the skin is not red Or it is light red, most of which can only be touched. The damage to the flattened round induration after the external hemorrhoids, the skin color is reddish, the surrounding tissue edema is obvious, all the damage is scattered, and it is rare to expand the fusion tendency.
Systemic symptoms vary according to the onset of the disease, usually sleepiness and discomfort, or loss of appetite, most cases are not fever, a few cases of low fever in the afternoon, increased after fatigue; or high fever within a few days before the onset of nodule, more special It is a small number of patients in the afternoon chills or even chills, followed by fever, midnight sweating and fever, the next morning as usual, no persistent high fever cases, lower limbs weakness and muscle pain during the attack period, if the damage is more, the lower part of the lower leg may appear Mild edema, migratory pain of the large joints of the extremities, more knee joints, no redness and dysfunction.
Examine
Examination of allergic skin nodular vasculitis
Blood, urine routine and liver and kidney function tests were normal; some cases were resistant to "O", erythrocyte sedimentation rate and mucin value were elevated; IgG, IgA values were generally normal; C3 or CIC values were low or slightly higher than normal; lymphocyte transformation test The value is generally low; the IL-2 value is low; the NK cell value is normal; the OT test (1:10000), and 50% of the cases are ~. Chest X-ray, some cases have old tuberculosis, occasionally active tuberculosis.
Diagnosis
Diagnosis and diagnosis of allergic skin nodular vasculitis
Diagnostic criteria
1. This disease occurs mostly in young and middle-aged women.
2. Damage below the buttocks, mainly calves.
3. The basic damage is subcutaneous nodules, distributed on both sides, not limited to calf extension or flexion.
4. Seasonal recurrent episodes, no rupture.
5. Less systemic symptoms, no other symptoms and signs of system involvement.
6. There are no other clear causes and incentives other than tuberculosis.
7. No complications such as reticular bluish and varicose veins.
Differential diagnosis
Inflammatory subcutaneous nodules of the lower extremities are a form of damage caused by pathogenic factors, which can be seen in a variety of diseases, their properties can be different, and the morphology is not significantly different, so it is difficult to identify, subcutaneous nodule damage occurs. Common diseases are Behcet syndrome, rare thrombophlebitis, rheumatism, leprosy, sarcoidosis, nodular panniculitis, deep lupus erythematosus, some swelling and nodular polyarteritis Such diseases, subcutaneous nodules in these diseases is only one of its systemic damage, its nature is different from nodular erythema, so the diagnosis should be based on systemic diseases, according to its form can be called the nodules of each disease Sexual erythema-like damage.
The other type is dermatitis with inflammatory subcutaneous nodules as the main clinical manifestations, mainly nodular erythema, hard erythema and nodular vasculitis. At present, the understanding of nodular vasculitis is vague and confusing. There is a need for further research, and a small number of cases of lower extremity inflammatory subcutaneous nodular lesions often require years of follow-up and careful observation to confirm the diagnosis.
