| K50919 | Crohn's disease, unspecified, with unspecified complications Crohn's disease, unspecified, with unspecified complications |
| K51 | Ulcerative colitis |
| K510 | Ulcerative (chronic) pancolitis |
| K5100 | Ulcerative (chronic) pancolitis without complications |
| K5101 | Ulcerative (chronic) pancolitis with complications |
| K51011 | Ulcerative (chronic) pancolitis with rectal bleeding |
| K51012 | Ulcerative (chronic) pancolitis with intestinal obstruction |
| K51013 | Ulcerative (chronic) pancolitis with fistula |
| K51014 | Ulcerative (chronic) pancolitis with abscess |
| K51018 | Ulcerative (chronic) pancolitis with other complication |
| K51019 | Ulcerative (chronic) pancolitis with unspecified complications |
| K512 | Ulcerative (chronic) proctitis |
| K5120 | Ulcerative (chronic) proctitis without complications |
| K5121 | Ulcerative (chronic) proctitis with complications |
| K51211 | Ulcerative (chronic) proctitis with rectal bleeding |
| K51212 | Ulcerative (chronic) proctitis with intestinal obstruction |
| K51213 | Ulcerative (chronic) proctitis with fistula |
| K51214 | Ulcerative (chronic) proctitis with abscess |
| K51218 | Ulcerative (chronic) proctitis with other complication |
| K51219 | Ulcerative (chronic) proctitis with unspecified complications |
| K513 | Ulcerative (chronic) rectosigmoiditis |
| K5130 | Ulcerative (chronic) rectosigmoiditis without complications |
| K5131 | Ulcerative (chronic) rectosigmoiditis with complications |
| K51311 | Ulcerative (chronic) rectosigmoiditis with rectal bleeding |
| K51312 | Ulcerative (chronic) rectosigmoiditis with intestinal obstruction |
| K51313 | Ulcerative (chronic) rectosigmoiditis with fistula |
| K51314 | Ulcerative (chronic) rectosigmoiditis with abscess |
| K51318 | Ulcerative (chronic) rectosigmoiditis with other complication |
| K51319 | Ulcerative (chronic) rectosigmoiditis with unspecified complications |
| K514 | Inflammatory polyps of colon |
| K5140 | Inflammatory polyps of colon without complications |
| K5141 | Inflammatory polyps of colon with complications |
| K51411 | Inflammatory polyps of colon with rectal bleeding |
| K51412 | Inflammatory polyps of colon with intestinal obstruction |
| K51413 | Inflammatory polyps of colon with fistula |
| K51414 | Inflammatory polyps of colon with abscess |
| K51418 | Inflammatory polyps of colon with other complication |
| K51419 | Inflammatory polyps of colon with unspecified complications |
| K515 | Left sided colitis |
| K5150 | Left sided colitis without complications |
| K5151 | Left sided colitis with complications |
| K51511 | Left sided colitis with rectal bleeding |
| K51512 | Left sided colitis with intestinal obstruction |
| K51513 | Left sided colitis with fistula |
| K51514 | Left sided colitis with abscess |
| K51518 | Left sided colitis with other complication |
| K51519 | Left sided colitis with unspecified complications |
| K518 | Other ulcerative colitis |
| K5180 | Other ulcerative colitis without complications |
| K5181 | Other ulcerative colitis with complications |