Overview
Goodpasture’s syndrome, also known as Goodpasture’s syndrome, is a rare autoimmune disease characterized by recurrent pulmonary hemorrhage followed by acute glomerulonephritis. The main pathological changes are massive crescent formation, which may be accompanied by capillary necrosis and intra-alveolar hemorrhage. Treatment should be comprehensive.
Etiology
The cause of this disease is not clear, but may be the result of a combination of etiologic factors, such as viral infection, chemical stimulation, or genetic factors, resulting in the production of autoantibodies against alveoli, pulmonary capillaries, and glomerular basement membranes, which lead to related tissue damage through hypersensitivity reactions.
Symptoms
Lung symptoms often begin with repeated hemoptysis, which is often the first symptom, ranging from a small amount of bloody sputum to hemoptysis with cough and shortness of breath; followed by nephritis, which can be seen as hematuria, proteinuria, oliguria, and often rapidly progresses to anuria, azotemia, and uremia. Anemia is common.X-ray examination shows diffuse or nodular shadows in both lungs, spreading from the lung hilar to the periphery, clear at the lung apices and near the diaphragm, and often heavier on one side.Some have no history of hemoptysis, but hemorrhage is confirmed by sputum ferritin-containing hemoglobin and chest radiography. In hemoptysis the lung diffusion function is reduced and hypoxemia occurs.
Examination
1. Urine routine
Microscopically, hematuria, erythrocyte tubular pattern, granulocyte tubular pattern, leukocytosis, most of them are moderate amount of urinary protein, and a few of them can see large amount of proteinuria.
2. Sputum examination
Microscopic examination of sputum shows macrophages with ferritin and bloody sputum.
3. Blood test
If the intrapulmonary hemorrhage is severe or prolonged, there may be more severe microcytic, hypochromic anemia, negative Coomb’s test, and half of the patients have leukocytes more than 10×109/L.
4. Blood biochemistry
Blood urea nitrogen (BUN), serum creatinine (Scr), creatinine clearance (Ccr) is normal in the early stage, but with the progress of the disease, BUN and Scr increase progressively, and Ccr decreases progressively, and the glomerular filtration rate (GFR) of the patients with severe renal hypoplasia is <5ml/min.
5. Immunologic examination
Early in the course of the disease, serum anti-glomerular basement membrane (GBM) antibodies are mostly positive by indirect immunofluorescence and radioimmunoassay, the sensitivity of indirect immunofluorescence is 80%, and the sensitivity of radioimmunoassay is more than 95%, and the specificity of the two methods can reach 99%.
6. Imaging
Lung X-ray shows diffuse punctate infiltration shadow, scattering from the lung portal to the periphery, and the tip of the lung is often clear, lung infiltration is the characteristic of lung lesions, lung X-ray changes in the early stage are similar to pulmonary edema, which can be absorbed in a short period of time after the cessation of hemoptysis.
7. Electron microscopy
(1) Lungs: typical lesions are alveolar hemorrhage, deposition of ferritin and fibrosis, which can be seen as alveolar wall capillary basement membrane degeneration, fracture and focal hyperplasia, deposition of electron dense material, and immunofluorescence can see linear deposition of IgG and C3.
(2) Kidney: typical lesions include: ① diffuse glomerular damage, the kidney is often enlarged and there are a large number of crescent formation, crescent is peripheral (extracapillary proliferative nephritis), can be accompanied by capillary necrosis, along the GBM there are line-like deposition of IgG; ② severe glomerular atrophy, the emergence of diffuse glomerular fibrosis and interstitial fibrosis, electron microscopy can be seen in the degeneration of the basement membrane of the glomeruli fracture, crumpling or Diffuse thickening.
8. Light microscopy
Most of the glomerular crescents are formed (more than 50%), and most of the crescents are of the same type.
9. Immunofluorescence
Linear deposits (mainly IgG, IgA, IgM, C3 and fibrinogen) can be seen along the endothelium of the glomerular basement membrane. If the deposits are high and low granular, the pulmonary renal syndrome is caused by other diseases.
Diagnosis
Diagnosis can be made on the basis of history, clinical manifestations, and examination, and anti-glomerular basement membrane (GBM) antibody is a specific indicator for the diagnosis of pulmonary hemorrhage-renal syndrome.
Treatment
Comprehensive treatment is used, and plasma replacement is used in combination with corticosteroids and cyclophosphamide, etc., which can remove and reduce the concentration of serum anti-glomerular basement membrane antibodies, and at the same time remove α and β complements, etc., which have a damaging effect on the body’s tissues. In cases where plasma exchange and hormone and immunosuppressive therapy are ineffective, bilateral nephrectomy may be considered. Peritoneal dialysis is suitable for those with obvious pulmonary hemorrhage.
1. Intensive plasma exchange therapy
Replace 2L of plasma each time, once a day or every other day. Cooperate with prednisone, taper to maintenance amount after 3 months; cyclophosphamide, stop the drug after accumulating 6~8g.
2. Methylprednisolone shock therapy
Methylprednisolone dissolved in 5% dextrose 200 ml of static drip, once a day or every other day, 3 times for a course of treatment, the interval of 3 ~ 5 days, with 3 courses of treatment. Supplemented with prednisone and cyclophosphamide orally.
3. Dialysis treatment and kidney transplantation
When acute renal failure meets the indications of dialysis, dialysis should be performed in time, and maintenance dialysis or renal transplantation should be performed in the late stage.
Prognosis
The prognosis is related to the extent of the lesion. If the glomerular crescent formation is less than 80%, the prognosis is good. If no timely measures are taken, patients often die of pulmonary hemorrhage or renal failure.