Churg-strauss syndrome (CSS), also known as allergic granulomatous vasculitis, is characterized pathologically by massive eosinophil infiltration and extravascular granuloma formation and necrotizing vasculitis in the affected tissue. Churg and Strauss first reported 13 cases with asthma, eosinophilia, granulomatous inflammation, necrotizing systemic vasculitis, and necrotizing glomerulonephritis in 1951, hence the name. Because asthma is the main feature of the disease and asthma can occur years before the appearance of vasculitis or the diagnosis of CSS. Therefore, it is important to think about CSS during the diagnosis and management of asthma, and to be more alert to CSS when encountering elevated eosinophils in the blood or tissues of asthmatic patients, although eosinophils can also be elevated in asthmatic patients. I. Diagnostic criteria 1. Asthma. 2, peripheral blood eosinophil count over 1.5×109/L. 3, typical systemic vasculitis involving two or more extra-pulmonary organs. 2. how to diagnose and treat 1. familiar with common CSS involved organs and their special manifestations, such as: nose: sinusitis, allergic rhinitis, multiple nasal polyps; lungs: common pulmonary infiltrative shadow, occasional pulmonary hemorrhage, rare diffuse interstitial lung changes; skin: rash, palpable purpura, subcutaneous nodules at the site of compression; kidneys: glomerulonephritis, hypertension; gastrointestinal: abdominal pain, blood in stool; heart. Heart rhythm disturbance, myocardial infarction, heart failure; Nerves: pain, weakness; If a patient with asthma, presents with the above manifestations, be alert to the possibility of CSS. 2, keep in mind the diagnostic criteria of CSS: 4 or more of the 6 articles are met to consider the diagnosis of the disease. 3, treatment: CSS treatment hormones are effective, but the dose should be individualized. Combined cyclophosphamide therapy is necessary when hormonal efficacy alone is unsatisfactory. CSS is usually a fatal disease prior to hormonal therapy. Early and effective treatment has a better prognosis, with a 1-year survival rate of 90% for treated CSS and a 5-year survival rate of 62%. The 5-year survival rate for untreated CSS is 25%. Therefore, it is the responsibility of each of our doctors to diagnose CSS early and correctly and to provide timely and effective treatment.