What is alveolar protein deposition disease and what is its prevalence? Alveolar protein deposition disease has a prevalence of about 4 per million and is a rare disease of the respiratory system. Existing studies have found that the disease is mainly due to the presence of autoantibodies in the body, which is called autoimmune alveolar protein deposition; if it is complicated by other systemic diseases, such as hematologic diseases, this type is called secondary alveolar protein deposition; there are also a small number of genetic factors associated with the disease, called congenital alveolar protein deposition. More than 90% of alveolar protein deposits are autoimmune or idiopathic. Is there a genetic link between autoimmune or idiopathic alveolar protein deposition? Hereditary cases are most often seen in children and are caused by genetic variants. However, the majority of patients have idiopathic or autoimmune disease, and this type is not associated with genetic factors. What factors can cause this disease? The triggering factors for autoimmune or idiopathic alveolar protein deposition are not well understood. However, the pathogenesis suggests that an autoantibody, anti-GM-CSF neutralizing antibody, is present in the alveoli and blood of this patient. The presence of this antibody destabilizes the alveolar environment, which is a stable and constantly circulating internal environment, and causes the accumulation of substances that should be circulated away, and this abnormal accumulation looks protein-like under the microscope, hence the name alveolar protein deposition disease. External factors are mainly related to dust in the environment, especially metal dust. Inadequate protective measures in some factories can increase the chance of workers getting sick. What age group does it occur in? The disease develops mainly between the ages of 30-40, with most patients being very young and occurring in both men and women. What are the symptoms of the disease? The disease progresses very insidiously and slowly, and it is difficult for patients to realize it is the disease at first. The alveoli are an important part of the respiratory system, and as more and more material builds up inside the alveoli that should not be there, the patient gradually develops symptoms such as wheezing or even difficulty breathing. Many patients are discovered by chance, for example, when a chest X-ray is taken due to a cold or pneumonia, and the film shows abnormalities in the lungs, and then the disease is discovered after careful examination; some patients may have more pronounced shortness of breath, or the symptoms of shortness of breath and dyspnea are discovered only after physical activity, especially after climbing stairs, which is more likely to produce shortness of breath and dyspnea compared to ordinary people; of course, some other symptoms may appear, such as coughing and coughing, but shortness of breath and dyspnea are the most common. Will the patient have more sputum? The amount of sputum does not increase significantly, and the main symptom is dyspnea.