Skip to main content
ICD-10/D46.9

D46.9 ICD-10-CM Code: Myelodysplastic syndrome, unspecified

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Inpatient Payment Groups (MS-DRG)

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0 (FY2026), Appendix B.

  • MS-DRG 811 — RED BLOOD CELL DISORDERS WITH MCC (MDC 16)
  • MS-DRG 812 — RED BLOOD CELL DISORDERS WITHOUT MCC (MDC 16)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

  • HCC 19 — Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers (supersedes HCC 20, HCC 21, HCC 22, HCC 23)

Other models: CMS-HCC V22 HCC 46 · RxHCC V08 HCC 19

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Code Set: Valid FY2026 and FY2027. FY2026 took effect October 1, 2025.

Official Registry Overview & Definition

Myelodysplastic syndrome, unspecified is a billable ICD-10-CM diagnosis code (D46.9).

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for D46.9 in the official ICD-10-CM tabular list.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Myelodysplasia NOS

Excludes1 — Not Coded Here

Conditions that can never be reported with this code; the two are mutually exclusive.

  • neoplasms of unspecified behavior (D49.-)

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

  • drug-induced aplastic anemia (D61.1)

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)

Nearest Codes in This Family

Official ICD-10-CM classifications closest to D46.9 in its code family, with their registry titles.

  • D46.1 — Refractory anemia with ring sideroblasts
  • D46.2 — Refractory anemia with excess of blasts [RAEB]
  • D46.20 — Refractory anemia with excess of blasts, unspecified
  • D46.21 — Refractory anemia with excess of blasts 1
  • D46.22 — Refractory anemia with excess of blasts 2
  • D46.4 — Refractory anemia, unspecified
  • D46.A — Refractory cytopenia with multilineage dysplasia
  • D46.B — Refractory cytopenia with multilineage dysplasia and ring sideroblasts
  • D46.C — Myelodysplastic syndrome with isolated del(5q) chromosomal abnormality
  • D46.Z — Other myelodysplastic syndromes

View all codes in the D46 family

Indexed Clinical Terms (6)

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.

  • Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), myelodysplastic
  • Myelodysplasia
  • Myelodysplastic syndrome
  • Preleukemia (syndrome)
  • Syndrome, myelodysplastic
  • Syndrome, preleukemic