Excludes1 pair

I70.1 vs N28.0

I70.1 and N28.0 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 N28.0
atherosclerosis of renal artery (extrarenal part) (I70.1)
I70.1

Atherosclerosis of renal artery

Billable
Chapter 9
Diseases of the circulatory system
Section
I70-I79
Use when the record says
  • Goldblatt's kidney
Indexed under
  • Goldblatt's hypertension or kidney
  • Hypertension, hypertensive › Goldblatt's
  • Stenosis, stenotic › renal artery
  • Stricture › renal artery
  • Arteriosclerosis, arteriosclerotic › renal › artery
N28.0

Ischemia and infarction of kidney

Billable
Chapter 14
Diseases of the genitourinary system
Section
N25-N29
Use when the record says
  • Renal artery embolism
  • Renal artery obstruction
  • Renal artery occlusion
  • Renal artery thrombosis
  • Renal infarct
Indexed under
  • Crisis › renal
  • Embolism › kidney (artery)
  • Embolism › renal (artery)
  • Infarct, infarction › brewer's (kidney)
  • Infarct, infarction › kidney

These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.

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