1, pus: the amount of pus, depending on the length and size of the fistula. The new anal fistula has more pus, thick pus, odor, yellow color, then gradually reduced, sometimes not, white, thin quality. If there is a sudden increase in pus, it means that a new fistula has been created. Sometimes the external mouth is temporarily closed, the flow of pus stops, the body temperature rises, local swelling, and an abscess is formed again. The closed external opening is then punctured or another new external opening is formed, and pus flows out again. If the internal or external fistula is thick, sometimes feces and gas flow out from the external mouth. Pain: If the fistula drains freely, there is usually no pain, but only a feeling of swelling and discomfort at the external opening, which increases when walking. Itching: The skin around the anus feels moist and itchy due to the frequent stimulation of secretions, and skin discoloration and epidermal peeling may occur. 4, poor defecation: mostly seen in hoof-shaped anal fistula, because the fistula around the anal canal, forming a semi-annular fibrous ring, thus affecting the anal diastasis, can appear poor defecation. 5, systemic symptoms: long duration of the disease will make the body wasting, anemia, constipation and defecation difficulties and other symptoms.