Left-sided ulcerative (chronic) colitis

This code signifies a chronic inflammatory bowel disease specifically affecting the left side of the colon, characterized by ulceration of the colonic mucosa. It represents a persistent form of ulcerative colitis confined to the descending colon, sigmoid colon, and rectum.

Apply this code when documentation specifies ulcerative colitis localized to the left colon, often described as "left-sided colitis" or "distal colitis." This diagnosis is typically confirmed by colonoscopy with biopsy showing chronic inflammation and ulceration limited to the left-sided segments.

• Ensure documentation explicitly states "left-sided" or specifies involvement of the descending colon, sigmoid, or rectum.
• Do not use for pancolitis or proctitis alone; those have more specific codes.
• Consider sequencing with codes for associated complications, such as anemia or toxic megacolon, if present.