N13.4 vs N28.8
N13.4 and N28.8 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on N28.8
hydroureter (N13.4)
N13.4
Hydroureter
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N10-N16
Indexed under
- Hydroureter
- Dilatation › ureter › due to obstruction
N28.8
Other specified disorders of kidney and ureter
Not billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N25-N29
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027