Excludes1 pair

N18- vs N19

N18 and N19 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

The official note, declared on N19
chronic kidney disease (N18.-)
N18

Chronic kidney disease (CKD)

Not billable
Chapter 14
Diseases of the genitourinary system
Section
N17-N19
N19

Unspecified kidney failure

BillableUnspecified
Chapter 14
Diseases of the genitourinary system
Section
N17-N19
Use when the record says
  • Uremia NOS
Indexed under
  • Uremia, uremic
  • Azotemia › meaning uremia
  • Failure, failed › kidney
  • Failure, failed › renal
  • Stasis › kidney

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