ICD-10 Code K60.40 – Rectal fistula, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K60.40 – Rectal fistula, unspecified
What it is
This code identifies a rectal fistula when the record does not specify the exact type or cause. It indicates an abnormal passage involving the rectum that is documented, but not further characterized.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings may include persistent drainage, local irritation, pain, or a visible tract, but you should code only what is clearly documented.
When to use this code
Use K60.40 when the provider documents a rectal fistula and does not identify a more specific diagnosis. It also fits when the note confirms the condition but leaves the exact anatomy or etiology unspecified. If the chart later clarifies the fistula type, update the code accordingly.
Do not use for
Do not use this code for anal fistula, perianal disease, or other anorectal conditions unless the rectum is specifically documented. Check documentation when the record describes a different fistula location.
Coding tip
Assign the most specific fistula code supported by the note; use K60.40 only when the documentation remains nonspecific.