ICD-10-CM 2027
ICD-10 code for myelodysplastic syndrome
From the official ICD-10-CM alphabetic index entry “Myelodysplastic syndrome”. Page updated September 29, 2026.
About coding myelodysplastic syndrome
The ICD-10-CM code for myelodysplastic syndrome is D46.9 (Myelodysplastic syndrome, unspecified). The official index lists 3 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on D46.9.
Within D46, choose D46.9 (Myelodysplastic syndrome, unspecified) only when documentation doesn't support a more specific option: refractory anemia without ring sideroblasts, so stated (D46.0), refractory anemia with ring sideroblasts (D46.1), refractory anemia with excess of blasts [RAEB] (D46.2), refractory anemia, unspecified (D46.4), refractory cytopenia with multilineage dysplasia (D46.A), refractory cytopenia with multilineage dysplasia and ring sideroblasts (D46.B), myelodysplastic syndrome with isolated del(5q) chromosomal abnormality (D46.C) and other myelodysplastic syndromes (D46.Z).
Use an additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
More specific myelodysplastic syndrome codes (official index)
Common questions about myelodysplastic syndrome ICD-10 codes
What is the ICD-10 code for myelodysplastic syndrome?
- D46.9 — Myelodysplastic syndrome, unspecified. More specific codes apply when the documentation supports them: D46.C, D46.C, D46.Z.
Is D46.9 billable?
- Yes. D46.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D46.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D46.9 as a principal diagnosis.
Is D46.9 a CC or MCC?
- No. D46.9 is neither a CC nor an MCC under MS-DRG v44.0.