cutaneous leukocytoclastic vasculitis
Introduction
Introduction to cutaneous leukocyte vasculitis Cutaneous leukocytoclasticvasculitis (CLV) is a vascular inflammatory lesion involving only the skin caused by a variety of causes. The pathological manifestations are neutrophil infiltration and nuclear fragmentation. Systemic vasculitis with skin manifestations should be excluded from diagnosis. basic knowledge The proportion of illness: 0.003% Susceptible people: no special people Mode of infection: non-infectious Complications: systemic vasculitis
Cause
Causes of cutaneous leukocyte vasculitis
Infection (25%):
Bacteria (Streptococcus, Mycobacterium tuberculosis, M. leprae, etc.), viruses (B and C viruses, Epstein-Barr virus), fungi (Candida), protozoa (Plasmodium, trypanosomes), worms (Schistosomiasis), etc.
Drugs (20%):
The application of penicillin, sulfonamides, aspirin, etc. can induce the occurrence of this disease. Naproxen and methotrexate also have reports of this disease. In addition, heterologous protein serum and insecticides can also be the cause of this disease.
Immune abnormality (15%):
The patient may have cryoglobulin, hypergammaglobulinemia, hereditary Q deficiency and the like.
Pathogenesis
Mainly for immune complex type allergic reaction, antigen and antibody are bound to deposit on small blood vessel wall, activate complement, cause mast cell degranulation, release histamine, make capillaries dilate, increase permeability; release leukocyte chemotactic factor attract Neutrophils accumulate in the local blood vessel wall, causing vasculitis, destruction of white blood cells, dissolution of collagenase and strong proteases can also destroy the blood vessel wall and cause vasculitis. Patients often have hypo-complementemia, and capillaries can be seen at early lesions. Vascular and capillary venous infiltration of neutrophils, nuclear fragmentation, swelling of endothelial cells, necrosis of the wall, fibrin deposition, etc., red blood cell overflow around the blood vessels, sometimes eosinophils, mononuclear cell infiltration, blood vessel wall The deposition of immunoglobulin and complement C3 can be seen. This change usually occurs before neutrophil infiltration and vascular wall destruction. The late damage is characterized by lack of lymphocyte infiltration.
Prevention
Skin leukocyte vasculitis prevention
Early diagnosis, early treatment, as far as possible to find the pathogen, symptomatic treatment. Primary prevention: smoking cessation is an important measure to prevent and treat vasculitis. Comprehensive data from home and abroad, 80% to 95% of smokers in patients, clinical observation found that smoking cessation can relieve pain, stable condition, re-smoking Symptoms are aggravated, so patients should be patiently advised not to smoke.
Complication
Complications of cutaneous leukocyte vasculitis Complications systemic vasculitis
This disease with organ damage should pay attention to whether it is the skin manifestation of systemic vasculitis, it is found that some patients with this disease are precancerous.
Symptom
Skin leukocyte rupture angiitis symptoms Common symptoms Blood blister systemic vasculitis pruritus myalgia nodule pustule reticular leukoplakia
There may be irregular fever, myalgia and joint pain. Skin damage is mostly distributed in the lower limbs. It is more common in the lower leg and the back of the foot. Sometimes the thigh, buttocks, trunk and upper limbs may also appear. The skin lesions are diverse, and the acute phase can be Batch appearance, purpura ecchymosis is the most common, characteristic, often higher than the leather surface, the pressure does not fade, there may be wheal erythema, severe blister, blood blisters, neutrophils ooze into the surrounding tissue There may also be pustules, sometimes subcutaneous nodules of varying sizes. If the vascular endothelium is damaged, local ulcers and necrosis may occur due to stenosis of the lumen, occasionally reticular leukoplakia, rash sometimes accompanied by itching or pain, generally lasting 2 ~ 4 weeks, after absorption may have pigmentation or residual atrophic scar, the disease may sometimes overlap with systemic vasculitis, should pay attention to make a diagnosis.
Examine
Examination of cutaneous leukocyte vasculitis
White blood cells are generally normal, sometimes elevated, platelets can be reduced in the acute rash period, erythrocyte sedimentation rate increases, serum complement is reduced, some patients can detect cryoglobulin, anti-cardiolipin antibodies (more common in IgA type).
Histopathological examination.
Diagnosis
Diagnosis and differentiation of leukoencephaloma vasculitis
According to the characteristics of young adults, the polymorphous skin lesions of the calves and the back of the feet, especially the palpable rash-like rash, should be considered.
Should pay attention to the exclusion of systemic vasculitis with skin manifestations, such as Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome, allergic purpura, cryoglobulinemia vasculitis, some cases follow the system In the case of sexual organ damage, the diagnosis should be corrected for systemic vasculitis. When the pathology of the disease has immune complex deposition, the risk of allergic purpura and cryoglobulin vasculitis increases; when the serum is detected anti-neutrophil In the case of cellular cytoplasmic antibodies, Wegener's granulomatosis, microscopic polyangiitis, and increased risk of Churg-Strauss syndrome.
