N12 Tubulo-interstitial nephritis, not specified as acute or chronic

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applicable to

• Interstitial nephritis NOS
• Pyelitis NOS
• Pyelonephritis NOS

Excludes1 (never code together)

• calculous pyelonephritis (N20.9)

Applies from N12 Tubulo-interstitial nephritis, not specified as acute or chronic

Applicable to

• Interstitial nephritis NOS
• Pyelitis NOS
• Pyelonephritis NOS

Excludes1 (never code together)

• calculous pyelonephritis (N20.9)

MS-DRG index

Defines the logic of DRG(s) 689-690 in MDC 11.

Approximate ICD-9-CM (GEMs)

• 590.80 Pyelonephritis, unspecified (approximate)

Code annotations containing back-references to N12

Back-references to N12

• Type 1 Excludes: N05 Unspecified nephritic syndrome ("tubulo-interstitial nephritis NOS (N12)")

Back-references to N12

• Type 1 Excludes: N05 Unspecified nephritic syndrome ("tubulo-interstitial nephritis NOS (N12)")

Diagnosis Index entries for N12

• Disease, diseased › antiglomerular basement membrane (anti- GBM) antibody › tubulo-interstitial nephritis
• Disease, diseased › renal (functional) (pelvis) › with › interstitial nephritis
• Nephritis, nephritic (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic) › antitubular basement membrane (tubulo-interstitial) NEC
• Nephritis, nephritic (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic) › tubulo-interstitial (in)
• Pyelonephritis › nonobstructive
• Pyonephritis

Nearby codes

• N12 Tubulo-interstitial nephritis, not specified as acute or chronic (this code)