ICD-10/K51.913

K51.913 ICD 2026 Code: Ulcerative colitis, unspecified with fistula

K51.913 is the authoritative medical code for Ulcerative colitis, unspecified with fistula. This classification is used in medical billing and clinical recording to specify the clinical criteria for ulcerative colitis, unspecified with fistula (ICD-10-CM K51.913), ensuring healthcare documentation aligns with 2026 federal coding standards.

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Official Registry Overview & Definition

Ulcerative colitis, unspecified with fistula is a billable ICD-10-CM diagnosis code K51.913. Includes: noninfective inflammatory bowel disease. Excludes1 (not coded here): Crohn's disease regional enteritis; irritable bowel syndrome K58.-; megacolon K59.3-. Use additional code: code to identify any associated fistulas, if applicable:; anal fistula K60.3-; anorectal fistula K60.5-; rectal fistula K60.4-; code to identify manifestations, such as:; pyoderma gangrenosum L88.

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for K51.913 in the official ICD-10-CM tabular list.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • noninfective inflammatory bowel disease

Excludes1 — Not Coded Here

Conditions that can never be reported with this code; the two are mutually exclusive.

  • Crohn's disease regional enteritis
  • irritable bowel syndrome K58.-
  • megacolon K59.3-

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • code to identify any associated fistulas, if applicable:
  • anal fistula K60.3-
  • anorectal fistula K60.5-
  • rectal fistula K60.4-
  • code to identify manifestations, such as:
  • pyoderma gangrenosum L88

Frequently Asked Questions (FAQ) & Clinical Guidance

What can't be coded together with K51.913?

Per official ICD-10-CM Excludes1 instructions, K51.913 must not be reported together with: Crohn's disease [regional enteritis] (K50.-); irritable bowel syndrome (K58.-); megacolon (K59.3-).

Is an additional code needed with K51.913?

Use additional code(s) to specify: code to identify any associated fistulas, if applicable:; anal fistula (K60.3-); anorectal fistula (K60.5-); rectal fistula (K60.4-).

Nearest Codes in This Family

Official ICD-10-CM classifications closest to K51.913 in its code family, with their registry titles.

  • K51 — Ulcerative colitis
  • 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

View all 40 codes in the K51 family

Indexed Clinical Terms (1)

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.

  • Colitis (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic), ulcerative (chronic), with, complication, fistula