M90 vs N25.0
M90 and N25.0 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 M90
renal osteodystrophy (N25.0)
M90
Osteopathies in diseases classified elsewhere
Not billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M86-M90
N25.0
Renal osteodystrophy
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N25-N29
Use when the record says
- Azotemic osteodystrophy
- Phosphate-losing tubular disorders
- Renal rickets
- Renal short stature
Indexed under
- Phosphate-losing tubular disorder
- Pseudorickets (renal)
- Disorder › phosphate-losing tubular (of)
- Disorder › tubular, phosphate-losing (of)
- Dwarfism › renal
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