N13.2 vs N20
N13.2 and N20 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 N20
that with hydronephrosis (N13.2)
N13.2
Hydronephrosis with renal and ureteral calculous obstruction
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N10-N16
Indexed under
- Calculus, calculi, calculous › ureter › with hydronephrosis
- Calculus, calculi, calculous › urinary › with hydronephrosis
- Calculus, calculi, calculous › kidney › with calculus, ureter › with hydronephrosis
- Calculus, calculi, calculous › kidney › congenital › with hydronephrosis
- Calculus, calculi, calculous › ureter › with calculus, kidney › with hydronephrosis
N20
Calculus of kidney and ureter
Not billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N20-N23
Use when the record says
- Calculous pyelonephritis
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