If the patient has symptoms such as cough, sputum, chills, fever, etc., lung infection is most likely to be considered, and anti-inflammatory therapy should be given. Second, if the patient does not have the above symptoms, the discovery of lung flaky shadow can also be seen in the infection, can also be seen in allergic diseases, need to ask the patient has no allergies to pollen, the surrounding environment, whether in the moldy place to stay, in addition to do the relevant examination to further clarify. Third, non-infectious diseases, such as vasculitis and other rare diseases can also cause lung flaky shadow, need to be further examined and excluded.