N11.9
Chronic tubulo-interstitial nephritis, unspecified
Billable FY2026 2025-10-01 → 2026-09-30
This is the unspecified option. 3 more
specific codes sit alongside it. Worth
checking whether the documentation supports one of them.
Exclusions 9 never code together
N00-N99chapter
Excludes2
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 8
N11.9code
Inclusion terms
- Chronic interstitial nephritis NOS
- Chronic pyelitis NOS
- Chronic pyelonephritis NOS
N11code
Includes
- chronic infectious interstitial nephritis
- chronic pyelitis
- chronic pyelonephritis
Use additional code
- code (B95-B97), to identify infectious agent.B95-B97
N10-N16block
Includes
- pyelonephritis
Index entries leading here 4
- Pyelitis (congenital) (uremic) — see also Pyelonephritis
- Pyelonephritis — see also Nephritis, tubulo-interstitial
- Pyelonephrosis (obstructive) N11.1
- chronic N11.9
- Nephritis, nephritic (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic) N05.9
Alongside this code 3 same parent — N11
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.