D56.2 vs D56.5
D56.2 and D56.5 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 D56.5
delta-beta thalassemia (D56.2)
D56.2
Delta-beta thalassemia
Billable
- Chapter 3
- Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
- Section
- D55-D59
Use when the record says
- Homozygous delta-beta thalassemia
Indexed under
- Thalassemia › delta-beta (anemia) (disease)
D56.5
Hemoglobin E-beta thalassemia
Billable
- Chapter 3
- Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
- Section
- D55-D59
Indexed under
- Hemoglobin › E-beta thalassemia
- Disease, diseased › hemoglobin or Hb › E-beta thalassemia
- Thalassemia › hemoglobin › E-beta (anemia) (disease)
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