D75.1 vs R71
D75.1 and R71 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 R71
polycythemia NOS (D75.1)
D75.1
Secondary polycythemia
Billable
- Chapter 3
- Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
- Section
- D70-D77
Use when the record says
- Acquired polycythemia
- Emotional polycythemia
- Erythrocytosis NOS
- Hypoxemic polycythemia
- Nephrogenous polycythemia
- Polycythemia due to erythropoietin
- Polycythemia due to fall in plasma volume
- Polycythemia due to high altitude
Indexed under
- Erythrocytosis (megalosplenic) (secondary)
- Gaisböck's disease (polycythemia hypertonica)
- Polycythemia (secondary)
- Polycytosis cryptogenica
- Pseudopolycythemia
R71
Abnormality of red blood cells
Not billable
- Chapter 18
- Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
- Section
- R70-R79
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