Symptoms of subcutaneous fistula include anal itching, wetness, pain, pus, blood discharge, and in severe cases, fever. Subcutaneous fistula is a kind of anal fistula, is a low anal fistula, is the lightest kind of anal fistula. Mainly due to sebaceous cysts caused by the local fistula, that is, in the subcutaneous can be found in the tube of the fistula. It does not invade upward into the anal sphincter. It is formed after a perianal abscess has broken down. In the early stages of the anal canal, thicker, yellowish, foul-smelling pus may be present, which gradually decreases and is sporadic. The environment near the anus is moist. There is pain and itching. Fever occurs in severe cases. When the symptoms are found, they should immediately go to the regular hospital for examination and surgical treatment under the guidance of professional doctors. It is recommended that patients should also pay attention to local hygiene and cleanliness in general, and should also pay attention to a light diet.