N05 vs N12
N05 and N12 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 N05
tubulo-interstitial nephritis NOS (N12)
N05
Unspecified nephritic syndrome
Not billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N00-N08
Use when the record says
- glomerular disease NOS
- glomerulonephritis NOS
- nephritis NOS
- nephropathy NOS and renal disease NOS with morphological lesion specified in .0-.8
N12
Tubulo-interstitial nephritis, not specified as acute or chronic
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N10-N16
Use when the record says
- Interstitial nephritis NOS
- Pyelitis NOS
- Pyelonephritis NOS
Indexed under
- Pyonephritis
- Nephritis, nephritic › antitubular basement membraneNEC (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
- Nephritis, nephritic › tubulo-interstitial (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
- Pyelonephritis › nonobstructive
- Disease, diseased › antiglomerular basement membraneantibody › tubulo-interstitial nephritis
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