ICDcodes.org
FY2027

N18.9 vs N28.9

N18.9 and N28.9 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 N28.9
chronic renal insufficiency (N18.9)
N18.9

Chronic kidney disease, unspecified

BillableUnspecified
Chapter 14
Diseases of the genitourinary system
Section
N17-N19
Use when the record says
  • Chronic renal disease
  • Chronic renal failure NOS
  • Chronic renal insufficiency
  • Chronic uremia NOS
  • Diffuse sclerosing glomerulonephritis NOS
Indexed under
  • Apoplexia, apoplexy, apoplectic › uremic
  • Glomerulonephritis › sclerosing, diffuse
  • Neuropathy, neuropathic › uremic
  • Paralysis, paralytic › uremic (complete) (incomplete)
  • Pericarditis › uremic (with decompensation) (with effusion)
N28.9

Disorder of kidney and ureter, unspecified

BillableUnspecified
Chapter 14
Diseases of the genitourinary system
Section
N25-N29
Use when the record says
  • Nephropathy NOS
  • Renal disease (acute) NOS
  • Renal insufficiency (acute)
Indexed under
  • Inefficiency, kidney
  • Nephropathy
  • Shutdown, renal
  • Block, blocked › kidney
  • Cachexia › renal

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