nonspecific systemic necrotizing small vessel vasculitis
Introduction
Introduction to non-specific systemic necrotizing small vasculitis Non-specific systemic necrotizing small vessel vasculitis (nonspecific systemicsmallvesselnecrotizingvasculitisSVN), formerly known as microscopic polyarteritis under the microscope, is now the most common disease called microscopic polyangiitis (microscopic polyangiitis MPA), it is a more common Necrotic vasculitis, the incidence of vasculitis is second only to Wegener granulomatosis. In 1994, Jennette proposed a new type of vasculitis-ANCA-associated vasculitis based on the positive or negative ANCA of patients with necrotizing vasculitis. Including Wegener granulomatosis, microscopic polyangiitis and Churg-Strauss syndrome, this concept has been widely accepted by experiments by many scholars at home and abroad. It has become a hot topic in vasculitis research at home and abroad, because according to a British study, 50% of all cases of necrotizing vasculitis belong to ANCA-associated vasculitis, and some foreign experts have developed new diagnostic criteria. basic knowledge The proportion of illness: 0.003% Susceptible people: no special people Mode of infection: non-infectious Complications: respiratory failure
Cause
The cause of non-specific systemic necrotizing small vasculitis
(1) Causes of the disease
The cause is unknown.
(two) pathogenesis
Nonspecific systemic small vessel necrotizin gvasculitis SVN, formerly known as microscopic polyarteritis under the microscope, is now the internationally accepted microscopic polyangiitis MPA. ), it is a more common necrotizing vasculitis, the main lesions are pulmonary capillary vasculitis, diffuse alveolar hemorrhage, alveolar septum and interstitial neutrophil infiltration, visible red blood cells and nuclear dust, some small blood vessels have thrombosis Formation and fibrinoid necrosis.
Prevention
Non-specific systemic necrotizing small vasculitis prevention
Should maintain a good working mood, care, considerate, encourage patients, do a full explanation, comfort work, avoid others talking about any troubles, excitement, and help patients overcome various lifestyle habits and hobbies that are not conducive to disease treatment.
Complication
Non-specific systemic necrotizing small vasculitis complications Complications, respiratory failure
Often combined with renal failure, resulting in death, the mortality caused by renal failure is higher than respiratory failure.
Symptom
Non-specific systemic necrotizing small vascular symptoms common symptoms hemoptysis respiratory failure hypoxemia renal failure alveolar hemorrhage
The incidence of lung lesions in this disease is 20% to 30%. There are typical triads in the clinic: hemoptysis, anemia and chest X-ray films show signs of alveolar hemorrhage, hemoptysis, anemia is a common symptom, and even fatal massive hemoptysis occurs. At the same time, due to the gas exchange disorder in the lungs, the patient may have severe hypoxemia. About 12% of the patients died of respiratory failure. The kidney damage rate is high and the symptoms are severe. The kidney damage is more than the lung performance. 70% have renal dysfunction, often combined with renal failure and cause death, the mortality caused by renal failure is higher than respiratory failure, chest radiograph is pulmonary congestion, bilateral lung field is blurred shadow, is alveolitis Sexual and congestive lesions, interstitial invasive changes, lesions are bilateral symmetry changes.
Examine
Examination of non-specific systemic necrotizing small vasculitis
1. Laboratory tests have elevated erythrocyte sedimentation rate, elevated C-reactive protein, and decreased hemoglobin.
2. Bronchoalveolar lavage fluid is bloody fluid, and there is phagocytic hemosiderin in macrophages.
3. Anti-neutrophil antibodies In recent years, the development of ANCA research has greatly improved the diagnosis rate of this disease. The ANCA antibody which is meaningful to this disease is the perinuclear ANCA (P-ANCA), and its antigen is myelin. Oxidase (MPO), its antigen-antibody complex is MPO-AN-CA. The combination of ELISA and immunofluorescence can make the positive rate of MPA diagnosis 70%, especially the high titer of MPO-ANCA for the diagnosis of MPA. Very high value.
X-ray films of the chest showed signs of alveolar hemorrhage, bilateral lung fields showed blurred shadows, alveolar inflammatory and congestive lesions, interstitial invasive changes, and bilateral symmetry changes.
The main lesions of lung biopsy were pulmonary capillary vasculitis, diffuse alveolar hemorrhage, alveolar septum and interstitial neutrophil infiltration, red blood cells and nuclear dust, and small blood vessels with thrombosis and fibrinoid necrosis.
Diagnosis
Diagnosis and differentiation of non-specific systemic necrotizing small vasculitis
Laboratory tests have erythrocyte sedimentation rate, elevated C-reactive protein, decreased hemoglobin, bronchoalveolar lavage fluid as bloody fluid, and hemophagocytic phagocytosis in macrophages. In recent years, the development of ANCA has improved the diagnostic rate of this disease. Great help, the ANCA antibody that is meaningful to this disease is the perinuclear ANCA (P-ANCA), the antigen is myeloperoxidase (MPO), and its antigen-antibody complex is MPO-AN-CA. Combined with immunofluorescence, the diagnostic positive rate of MPA can reach 70%, especially the high titer MPO-ANCA has very high value for the diagnosis of MPA, and the weight of the disease can be judged by monitoring the change of MPO-ANCA titer. Observing the curative effect and guiding treatment is the latest and most promising diagnostic technique for the diagnosis of this disease. The diagnosis of this disease still requires lung biopsy. The main lesions of the biopsy tissue are pulmonary capillary vasculitis, diffuse alveolar hemorrhage, alveolar septum and There are neutrophil infiltration, red blood cells and nuclear dust, and some small blood vessels have thrombosis and fibrinoid necrosis.
It should be differentiated from acute lung injury caused by lung infections and tumors, chemical inhalation.
