ICD-10-CM K51: Ulcerative colitis

ICD-10-CM Diagnosis Code (2025)

Official Description for K51

Ulcerative colitis

Coding Notes & Guidelines for K51

Excludes1: Not Coded Here

Crohn's disease [regional enteritis] (K50.-)

Excludes2: Not Included Here
  • adenomatous polyp of colon (D12.6)
  • polyposis of colon (D12.6)
  • polyps of colon NOS (K63.5)
Use Additional Code
  • code to identify any associated fistulas, if applicable:
  • anal fistula (K60.3-)
  • anorectal fistula (K60.5-)
  • rectal fistula (K60.4-)
Use Additional Code
  • code to identify manifestations, such as:
  • pyoderma gangrenosum (L88)
Inclusion Terms

Backwash ileitis

Inclusion Terms

Ulcerative (chronic) pancolitis NOS

Inclusion Terms

Ulcerative (chronic) proctitis NOS

Inclusion Terms

Ulcerative (chronic) rectosigmoiditis NOS

Inclusion Terms

Inflammatory polyps of colon NOS

Inclusion Terms

Left hemicolitis

Inclusion Terms

Left sided colitis NOS

Child Codes (More Specific Codes for K51):

K51.0 - Ulcerative (chronic) pancolitis K51.00 - Ulcerative (chronic) pancolitis without complications K51.01 - Ulcerative (chronic) pancolitis with complications K51.011 - Ulcerative (chronic) pancolitis with rectal bleeding K51.012 - Ulcerative (chronic) pancolitis with intestinal obstruction K51.013 - Ulcerative (chronic) pancolitis with fistula K51.014 - Ulcerative (chronic) pancolitis with abscess K51.018 - Ulcerative (chronic) pancolitis with other complication K51.019 - Ulcerative (chronic) pancolitis with unspecified complications K51.2 - Ulcerative (chronic) proctitis K51.20 - Ulcerative (chronic) proctitis without complications K51.21 - Ulcerative (chronic) proctitis with complications K51.211 - Ulcerative (chronic) proctitis with rectal bleeding K51.212 - Ulcerative (chronic) proctitis with intestinal obstruction K51.213 - Ulcerative (chronic) proctitis with fistula K51.214 - Ulcerative (chronic) proctitis with abscess K51.218 - Ulcerative (chronic) proctitis with other complication K51.219 - Ulcerative (chronic) proctitis with unspecified complications K51.3 - Ulcerative (chronic) rectosigmoiditis K51.30 - Ulcerative (chronic) rectosigmoiditis without complications K51.31 - Ulcerative (chronic) rectosigmoiditis with complications K51.311 - Ulcerative (chronic) rectosigmoiditis with rectal bleeding K51.312 - Ulcerative (chronic) rectosigmoiditis with intestinal obstruction K51.313 - Ulcerative (chronic) rectosigmoiditis with fistula K51.314 - Ulcerative (chronic) rectosigmoiditis with abscess K51.318 - Ulcerative (chronic) rectosigmoiditis with other complication K51.319 - Ulcerative (chronic) rectosigmoiditis with unspecified complications K51.4 - Inflammatory polyps of colon K51.40 - Inflammatory polyps of colon without complications K51.41 - Inflammatory polyps of colon with complications K51.411 - Inflammatory polyps of colon with rectal bleeding K51.412 - Inflammatory polyps of colon with intestinal obstruction K51.413 - Inflammatory polyps of colon with fistula K51.414 - Inflammatory polyps of colon with abscess K51.418 - Inflammatory polyps of colon with other complication K51.419 - Inflammatory polyps of colon with unspecified complications K51.5 - Left sided colitis K51.50 - Left sided colitis without complications K51.51 - Left sided colitis with complications K51.511 - Left sided colitis with rectal bleeding K51.512 - Left sided colitis with intestinal obstruction K51.513 - Left sided colitis with fistula K51.514 - Left sided colitis with abscess K51.518 - Left sided colitis with other complication K51.519 - Left sided colitis with unspecified complications K51.8 - Other ulcerative colitis K51.80 - Other ulcerative colitis without complications K51.81 - Other ulcerative colitis with complications K51.811 - Other ulcerative colitis with rectal bleeding K51.812 - Other ulcerative colitis with intestinal obstruction K51.813 - Other ulcerative colitis with fistula K51.814 - Other ulcerative colitis with abscess K51.818 - Other ulcerative colitis with other complication K51.819 - Other ulcerative colitis with unspecified complications K51.9 - Ulcerative colitis, unspecified K51.90 - Ulcerative colitis, unspecified, without complications K51.91 - Ulcerative colitis, unspecified, with complications K51.911 - Ulcerative colitis, unspecified with rectal bleeding K51.912 - Ulcerative colitis, unspecified with intestinal obstruction K51.913 - Ulcerative colitis, unspecified with fistula K51.914 - Ulcerative colitis, unspecified with abscess K51.918 - Ulcerative colitis, unspecified with other complication K51.919 - Ulcerative colitis, unspecified with unspecified complications

About ICD-10-CM Code K51 (Ulcerative colitis)

ICD-10-CM code K51 is a billable or specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. The 2025 edition of ICD-10-CM K51 became effective on October 1, 2024.

This page provides detailed information about K51 - Ulcerative colitis. It includes common terminology, coding guidelines such as "Includes," "Excludes1," and "Excludes2" notes, and information on required 7th characters. Utilizing this information correctly is essential for accurate medical coding and claims submission for conditions like Ulcerative colitis.