2026 ICD-10-CM Diagnosis Code D46.9Myelodysplastic syndrome, unspecified

ICD-10-CM Codes›C00–D49›D37-D48›D46

ICD-10-CM D46.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D46.9 is a billable ICD-10-CM diagnosis code for myelodysplastic syndrome, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 811 through 812. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Myelodysplastic syndrome (MDS).

Code Identity

ICD-10-CM Code
D46.9
Billable Status
Yes — Valid for Submission
Code Describes
Myelodysplastic syndrome, unspecified
Short Description
Myelodysplastic syndrome, unspecified
Same as the full description in the CMS dataset.
Parent Code
D46
Myelodysplastic syndromes

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD46Myelodysplastic syndromes
This CodeD46.9Myelodysplastic syndrome, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute myeloid leukemia and myelodysplastic syndrome related to alkylating agent
  • Acute myeloid leukemia and myelodysplastic syndrome related to radiation
  • Acute myeloid leukemia and myelodysplastic syndrome related to topoisomerase type 2 inhibitor
  • Childhood myelodysplastic syndrome
  • Congenital hypoplasia of adrenal gland
  • Disorder of bone marrow caused by ionizing radiation
  • Hematologic complication of procedure
  • MIRAGE syndrome
  • Myelodysplastic syndrome
  • Short stature co-occurrent and due to endocrine disorder
  • Therapy related acute myeloid leukemia and myelodysplastic syndrome
  • Therapy related acute myeloid leukemia due to and following administration of antineoplastic agent
  • Therapy-related myelodysplastic syndrome

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Myelodysplasia NOS

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

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

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO068
Myelodysplastic syndrome (MDS)
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Myelodysplastic Syndromes

    clonal hematopoietic stem cell disorders characterized by dysplasia in one or more hematopoietic cell lineages. they predominantly affect patients over 60, are considered preleukemic conditions, and have high probability of transformation into acute myeloid leukemia.

Patient EducationClinical

Myelodysplastic Syndromes

Your bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The stem cells can develop into the red blood cells that carry oxygen through your body, the white blood cells that fight infections, and the platelets that help with blood clotting.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert D46.9 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
238.75 Myelodysplastic synd NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About D46.9Overview

Is D46.9 (Myelodysplastic syndromes) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report myelodysplastic syndrome, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does D46.9 group to?

When myelodysplastic syndrome, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 811, 812, with relative weights from 0.9182 to 1.4043 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of D46.9?

Under the General Equivalence Mappings, myelodysplastic syndrome, unspecified converts to ICD-9-CM 238.75 (myelodysplastic synd NOS). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.