ICD-10 Code K60.42 – Rectal fistula, complex (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K60.42 – Rectal fistula, complex
What it is
K60.42 identifies a complex fistula involving the rectum. It is an abnormal tract that connects the rectum to nearby tissue and is more complicated than a simple fistula.
Clinical signs
Clinical features vary; refer to documentation. Typical findings include persistent drainage, recurrent infection, pain, or an opening near the rectum, with complexity noted by the provider.
When to use this code
Use K60.42 when the record clearly documents a complex rectal fistula. This may include cases described as branching, recurrent, or involving surrounding structures. Code it only when the provider specifies rectal location and complexity.
Do not use for
Do not use this code for simple anorectal fistulas or nonspecific perianal abscesses. Check documentation if the fistula is described only as anal, perianal, or unspecified.
Coding tip
Verify both the rectal site and the term “complex” in the note before assigning K60.42.