Ulcer of anus and rectum

This code represents an open sore or lesion affecting the mucosal lining of the anus, rectum, or both. These ulcers can result from various etiologies, including trauma, infection, ischemia, or inflammatory conditions, and may cause pain, bleeding, or discharge.

Assign this code when documentation specifies an ulceration of the anal or rectal mucosa, or both, that is not due to a fissure, fistula, or ulcerative colitis. Supporting documentation should clearly identify the presence and location of the ulcer, often noted during a physical examination (e.g., anoscopy, proctoscopy) or imaging studies.

• Differentiate carefully between an ulcer and a fissure; a fissure is a linear tear, while an ulcer is a deeper, often round or irregular, open sore.
• Review documentation to rule out ulcerative colitis (K51.-) as the underlying cause, as this is an Excludes1 condition.
• Code any associated underlying cause or complication, such as infection or bleeding, if documented.