ICD-10 Code K61.1 – Rectal abscess (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K61.1 – Rectal abscess
What it is
K61.1 identifies a localized collection of pus in or around the rectum. It is used when documentation specifically states a rectal abscess rather than a perianal or other anorectal abscess.
Clinical signs
Typical findings include rectal pain, tenderness, swelling, and sometimes drainage or fever. Clinical features vary; refer to documentation, especially when the record distinguishes rectal from adjacent perianal disease.
When to use this code
Use K61.1 when the provider documents a rectal abscess, including imaging, exam, or operative findings that support that location. Apply it when the diagnosis is clearly stated and not better described as a different anorectal abscess site. Check documentation if the location is unclear.
Do not use for
Do not use this code for perianal, anal, or other anorectal abscesses unless the record specifically says rectal. If the site is uncertain, check documentation rather than assuming K61.1.
Coding tip
Always code the abscess location exactly as documented, because anorectal abscess codes are site-specific.