| K51.30 | Ulcerative (chronic) rectosigmoiditis without complications | BILLABLE CODE |
| K51.31 | Ulcerative (chronic) rectosigmoiditis with complications | NON-BILLABLE CODE |
| K51.311 | Ulcerative (chronic) rectosigmoiditis with rectal bleeding | BILLABLE CODE |
| K51.312 | Ulcerative (chronic) rectosigmoiditis with intestinal obstruction | BILLABLE CODE |
| K51.313 | Ulcerative (chronic) rectosigmoiditis with fistula | BILLABLE CODE |
| K51.314 | Ulcerative (chronic) rectosigmoiditis with abscess | BILLABLE CODE |
| K51.318 | Ulcerative (chronic) rectosigmoiditis with other complication | BILLABLE CODE |
| K51.319 | Ulcerative (chronic) rectosigmoiditis with unspecified complications | BILLABLE CODE |
