Is N13.721 a billable ICD-10-CM code?

Yes. N13.721 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does N13.721 sit in the tabular list?

Diseases of the genitourinary system (N00-N99), in the block Renal tubulo-interstitial diseases (N10-N16).

What cannot be coded together with N13.721?

N13.721 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above N13.721 (N13.7) and apply to it just the same.

N13.721

N13.721 — Vesicoureteral-reflux with reflux nephropathy without hydroureter, unilateral

Billable / specific codeICD-10-CM

N13.721 is a billable, specific ICD-10-CM code for vesicoureteral-reflux with reflux nephropathy without hydroureter, unilateral. It is valid for submission on a claim.

Excludes1 inherited from the categories above N13.721

These are not written on N13.721, but they bind it: a note on a category applies to every code beneath it. Billing N13.721 with anything listed here is a denial.

Written on N13.7 — Vesicoureteral-reflux

reflux-associated pyelonephritis (N11.0)

Excludes2 inherited from the categories above N13.721

Also inherited, and the opposite of Excludes1: these conditions are not part of N13.721, but a patient can have both, so you may code both.

Written on N13 — Obstructive and reflux uropathy

calculus of kidney and ureter without hydronephrosis (N20.-)
congenital obstructive defects of renal pelvis and ureter (Q62.0-Q62.3)
hydronephrosis with ureteropelvic junction obstruction (Q62.11)
obstructive pyelonephritis (N11.1)

Other codes that can never be billed with N13.721

These codes carry an Excludes1 note pointing at N13.721. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading N13.721 alone.

N11.1Chronic obstructive pyelonephritis

Risk adjustment

N13.721 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

N13.721 is named in 3 Medicare coverage policies — 3 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56421Billing and Coding: CT of the Abdomen and Pelvis
A56802Billing and Coding: Urodynamics
A57455Billing and Coding: Urodynamics

How N13.721 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to N13.721.

Reflux›vesicoureteral›with›nephropathy›unilateral
Reflux›vesicoureteral›with›nephropathy›without hydroureter›unilateral

Code history

N13.721 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share N13.72. If N13.721 is not quite right, the correct code is usually one of these.

Questions about N13.721

Is N13.721 a billable ICD-10-CM code?: Yes. N13.721 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does N13.721 sit in the tabular list?: Diseases of the genitourinary system (N00-N99), in the block Renal tubulo-interstitial diseases (N10-N16).
What cannot be coded together with N13.721?: N13.721 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above N13.721 (N13.7) and apply to it just the same.