N00 vs N10
N00 and N10 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 N00
acute tubulo-interstitial nephritis (N10)
N00
Acute nephritic syndrome
Not billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N00-N08
Use when the record says
- acute glomerular disease
- acute glomerulonephritis
- acute nephritis
N10
Acute pyelonephritis
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N10-N16
Use when the record says
- Acute infectious interstitial nephritis
- Acute pyelitis
- Acute tubulo-interstitial nephritis
- Hemoglobin nephrosis
- Myoglobin nephrosis
Indexed under
- Nephrosis, nephrotic › hemoglobin (Epstein's) (syndrome) (congenital)
- Nephrosis, nephrotic › myoglobin (Epstein's) (syndrome) (congenital)
- Pyelitis › acute (congenital) (uremic)
- Pyelonephritis › acute
- Nephritis, nephritic › tubulo-interstitial › acute (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
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