K51.513
BillableLeft sided colitis with fistula
HCC Category Mapping
V28HCC 81 — Ulcerative Colitis
0.000V24HCC 35 — Inflammatory Bowel Disease
0.289ESRDHCC 35 — Inflammatory Bowel Disease
0.000RxHCCHCC 67 — Inflammatory Bowel Disease
0.000What This Code Means
Inflammation of the left side of the colon with an abnormal tunnel-like opening (fistula) connecting to other tissues or organs.
Coding Tips
- •Verify documentation specifies left-sided colitis and confirms presence of fistula before assigning this code
- •Consider if fistula location is documented (perianal, enterocutaneous, etc.) as this may affect treatment planning
Clinical Significance
Left-sided ulcerative colitis with fistula represents development of an abnormal connection between the inflamed left colon and adjacent structures. Fistula formation in ulcerative colitis is uncommon and should prompt careful evaluation of whether the diagnosis might actually be Crohn disease, which more characteristically produces fistulae.
Documentation Requirements
- ✓Confirmed left-sided ulcerative colitis diagnosis
- ✓Documentation of fistula type and location (colovesical, colovaginal, enterocutaneous)
- ✓Imaging confirmation of fistula (CT, MRI, or fistulogram)
- ✓Provider statement attributing fistula to the colitis
- ✓Surgical consultation and treatment plan
- ✓Documentation of diagnostic reconsideration regarding Crohn disease
Commonly Confused Codes
K51.513 vs K50.113 — K50.113 is Crohn disease of large intestine with fistula; verify diagnosis when fistula is presentK51.513 vs K60.3 — K60.3 is anal fistula unrelated to inflammatory bowel diseaseK51.513 vs K51.013 — K51.013 is pancolitis with fistula; left-sided is more limitedK51.513 vs K51.313 — K51.313 is rectosigmoiditis with fistula; left-sided extends further
Code Hierarchy
└K51Ulcerative colitis└K51.5Left sided colitis└K51.51Left sided colitis with complications└K51.513Left sided colitis with fistula
└K51.513Left sided colitis with fistula