Chronic blood diseases commonly include chronic leukemia, iron deficiency anemia, and allergic purpura, etc. The main clinical symptoms include pallor, loss of appetite, fever, and abdominal pain. 1. Chronic leukemia: common chronic granulocytic leukemia, chronic lymphocytic leukemia, etc. The onset of the disease may be related to infections, radiation factors, chemical factors, genetic factors, etc. Clinical fever, infections, bleeding are common symptoms. 2. Iron deficiency anemia: caused by insufficient iron intake, absorption obstacles, excessive consumption, etc., the main manifestations are pallor, loss of appetite, poor mental health. 3. Anaphylactic purpura: a kind of systemic vasculitis with small vessel vasculitis as the main lesion, the etiology of which is still unclear, mostly with acute onset, the first symptom of skin purpura as the main symptom, and abdominal pain and arthritic symptoms appear first in some cases. In addition, chronic blood diseases can also be seen in thalassemia, aplastic anemia, etc., mainly with anemia as the clinical manifestations, the specific diagnosis and treatment should be carried out under the guidance of physicians.