N13.4 vs Q62
N13.4 and Q62 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 N13.4
congenital hydroureter (Q62.3-)
N13.4
Hydroureter
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N10-N16
Indexed under
- Hydroureter
- Dilatation › ureter › due to obstruction
Q62
Congenital obstructive defects of renal pelvis and congenital malformations of ureter
Not billable
- Chapter 17
- Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders
- Section
- Q60-Q64
These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.
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