What are the symptoms of an anal fistula?

Anal fistula mainly presents the following symptoms: 1. Persistent pain: Most patients with anal fistula experience local persistent dull pain, which worsens after defecation due to fecal irritation of the inflamed tissue within the fistula tract. 2. Pus discharge: Patients may notice colorless or pale yellow pus draining from an opening around the anus, sometimes soiling underwear. This discharge often has a foul odor. 3. Skin ulcers: The perianal skin may become red, swollen, and tender. Over time, ulcers may develop in these areas. 4. Itching and discomfort: Due to irritation from the discharge, itching around the anus may develop, affecting quality of life. 5. Bowel movement abnormalities: Some patients may experience pain or discomfort during defecation; in severe cases, minor bleeding may accompany bowel movements. 6. Mass: A soft lump may be felt outside or near the anus, which represents the external opening of the fistula or a palpable portion of the fistula tract itself. If the above symptoms occur, timely medical consultation is necessary for examination and diagnosis by a qualified physician.