N11.9 — Chronic tubulo-interstitial nephritis, unspecified
N11.9 is a billable, specific ICD-10-CM code for chronic tubulo-interstitial nephritis, unspecified. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Chronic interstitial nephritis NOS
- Chronic pyelitis NOS
- Chronic pyelonephritis NOS
Risk adjustment
N11.9 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
N11.9 is named in 2 Medicare coverage policies — 2 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A55336Billing and Coding: Retroperitoneal Ultrasound
- A56421Billing and Coding: CT of the Abdomen and Pelvis
How N11.9 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 N11.9.
- Pyelitis›chronic
- Pyelonephritis›chronic
- Pyelonephrosis›chronic
- Nephritis, nephritic›tubulo-interstitial›chronic(infectious)
- Pyelitis›with›contracted kidney
- Pyelonephritis›with›contracted kidney
Related codes at this level
Codes that share N11. If N11.9 is not quite right, the correct code is usually one of these.
Questions about N11.9
- Is N11.9 a billable ICD-10-CM code?
- Yes. N11.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does N11.9 sit in the tabular list?
- Diseases of the genitourinary system (N00-N99), in the block Renal tubulo-interstitial diseases (N10-N16).