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D46.4 ICD-10-CM Code: Refractory anemia, unspecified

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

Coding at a Glance

Tabular directives
1 Excludes1 · 1 Excludes2 · 1 use-additional code
Risk adjustment
CMS-HCC V28: 1 category · CMS-HCC V22 category 46 · RxHCC V08 category 19

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

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

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for D46.4 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on D46.4 itself; “inherited from” names the category or block whose note applies here.

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from D37-D48

Excludes2 — Not Included Here

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

Source: inherited from D46

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)

Source: inherited from D46

Coder workflow for D46.4

MedCoder structured workflow — derived from this code’s own official record

Before you code D46.4

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, D46.4 may be the appropriate code. Check the record for detail that supports a more specific sibling — in this subcategory the siblings differ by the presence or absence of the associated condition. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).

    ReviewD46.0, D46.1, D46.2, D46.A, D46.B, D46.C, D46.Z

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  2. Confirm the documented site and behavior (this code’s block classifies uncertain behavior neoplasms), whether the site is primary or secondary, and whether the malignancy is current or a personal history: a previously excised malignancy with no further treatment and no evidence of disease is history, not current disease. Verify the site against the Table of Neoplasms. Neoplasm chapter guidelines (Guidelines I.C.2.a, I.C.2.d, I.C.2.m).

    See the Table of Neoplasms entries · Guide: Active cancer vs history of cancer →

  3. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with D46.4. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the record document the detail a more specific sibling code needs?
    Yes → Review the specific siblings in this subcategory.
    No → Continue — D46.4 is appropriate when the documentation goes no further.

    ReviewD46.0, D46.1, D46.2, D46.A, D46.B, D46.C, D46.Z

  2. Does the documentation support a condition named in D46.4’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewD49

Consider D46.4. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
The associated condition or complication
Whether the associated condition the title names is documented; the “with” convention presumes some links, and a provider statement that the conditions are unrelated defeats it (Guidelines I.A.15).
The conditions the Use Additional Code note names
Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
Behavior and current-versus-history status
Malignant, in situ, benign or uncertain; primary or secondary; current disease or personal history (Guidelines I.C.2.m).
Any detail beyond this code’s title
What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting D46.4(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with D46.4: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareD49

    See the official tabular notes · Guidelines I.A.12.a

  • Excludes2 — not part of D46.4(1 note)

    Coding workflow: The conditions named in this note are not included in D46.4. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareD61.1

    See the official tabular notes · Guidelines I.A.12.b

  • Use Additional Code — after identifying D46.4(1 note)

    Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with D46.4 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

    See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific sibling code supportable?

Path: Review the specific siblings in this subcategory and what each requires the record to state.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

ReviewD46.0, D46.1, D46.2, D46.A, D46.B, D46.C, D46.Z

Documentation: Both the condition D46.4 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewD49

Documentation: A condition the Use Additional Code note names is documented.

Coding question: Is a second code reported with D46.4?

Path: Review the Use Additional Code note and the code it names.

Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Code Overview

Refractory anemia, unspecified is a billable ICD-10-CM diagnosis code (D46.4).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Indexed Clinical Terms (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

  1. 1 Use Additional Code instruction — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
  2. 1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
  3. 1 Excludes2 entry — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

  • No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name D46.4 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 2 Excludes1 notes across 2 chapters: C94 — Other leukemias of specified cell type (via D46.-), D64 — Other anemias (via D46.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 1 Excludes2 note: D61.81 — Pancytopenia (via D46.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Use Additional Code instruction: D75.81 — Myelofibrosis (via D46.-).

These codes instruct coders to additionally report this code when it applies.

Referenced by 1 Code Also instruction: D61.02 — Shwachman-Diamond syndrome (via D46.-).

These codes suggest coding this condition alongside when both are present.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 2 MS-DRGs: DRG 811 (MDC 16), DRG 812 (MDC 16).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):NEO068 — Myelodysplastic syndrome (MDS) (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers) for risk-adjusted payment.

C91.31 — Prolymphocytic leukemia of B-cell type, in remission, C91.32 — Prolymphocytic leukemia of B-cell type, in relapse, C91.50 — Adult T-cell lymphoma/leukemia (HTLV-1-associated) not having achieved remission, C91.51 — Adult T-cell lymphoma/leukemia (HTLV-1-associated), in remission, C91.52 — Adult T-cell lymphoma/leukemia (HTLV-1-associated), in relapse, C91.60 — Prolymphocytic leukemia of T-cell type not having achieved remission, C91.61 — Prolymphocytic leukemia of T-cell type, in remission, C91.62 — Prolymphocytic leukemia of T-cell type, in relapse, C94.6 — Myelodysplastic disease, not elsewhere classified, D46.0 — Refractory anemia without ring sideroblasts, so stated, D46.1 — Refractory anemia with ring sideroblasts, D46.20 — Refractory anemia with excess of blasts, unspecified, D46.21 — Refractory anemia with excess of blasts 1, D46.9 — Myelodysplastic syndrome, 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, D47.4 — Osteomyelofibrosis, D75.81 — Myelofibrosis, +47 more

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic, Cancer Metastatic to Bone, Other and Unspecified Metastatic Cancer; Acute Leukemia Except Myeloid, Lung and Other Severe Cancers, Lymphoma and Other Cancers, Bladder, Colorectal, and Other Cancers, Prostate, Breast, and Other Cancers and Tumors

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Myelodysplastic syndrome (MDS)).

D46.0 — Refractory anemia without ring sideroblasts, so stated, D46.1 — Refractory anemia with ring sideroblasts, 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, D46.9 — Myelodysplastic syndrome, 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

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Anemia”; these codes share that main term but sit in a different category of the Tabular List.

A07.0 — Balantidiasis (Balantidium coli), A18.89 — Tuberculosis of other sites (tuberculous), A52.79 — Other symptomatic late syphilis (syphilitic), B54 — Unspecified malaria (marsh), B70.0 — Diphyllobothriasis (bothriocephalus), B76.1 — Necatoriasis (due to, Necator americanus), B76.9 — Hookworm disease, unspecified (miner's), D47.Z9 — Other specified neoplasms of uncertain behavior of lymphoid, hematopoietic and related tissue (myeloproliferative), D50.0 — Iron deficiency anemia secondary to blood loss (chronic) (blood loss), D50.8 — Other iron deficiency anemias (Witts'), D50.9 — Iron deficiency anemia, unspecified (Faber's), D51.0 — Vitamin B12 deficiency anemia due to intrinsic factor deficiency (Addison), D51.1 — Vitamin B12 deficiency anemia due to selective vitamin B12 malabsorption with proteinuria (megaloblastic, hereditary), D51.2 — Transcobalamin II deficiency (deficiency, transcobalamin II), D51.3 — Other dietary vitamin B12 deficiency anemia (vegan), D51.8 — Other vitamin B12 deficiency anemias (deficiency, vitamin B12 NOS, specified type NEC), D51.9 — Vitamin B12 deficiency anemia, unspecified (deficiency, vitamin B12 NOS), D52.0 — Dietary folate deficiency anemia (goat's milk), D52.1 — Drug-induced folate deficiency anemia (deficiency, folate, drug-induced), D52.8 — Other folate deficiency anemias (tropical, macrocytic), +68 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Gamma-glutamyl Transferase (GGT) Test, Iron Panel, Partial Thromboplastin Time (PTT) Test, Prothrombin Time Test and INR (PT/INR)

Contextual Map

Every relationship of D46.4 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run D46.4 with these 5 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Referenced by Excludes2 notes

  • D61.81 — Pancytopenia[Excludes2](via D46.-): “pancytopenia (due to) (with) myelodysplastic syndromes (D46.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Use Additional Code instructions

  • D75.81 — Myelofibrosis[Use Additional Code](via D46.-): “code, if applicable, for associated therapy-related myelodysplastic syndrome (D46.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code Also instructions

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

  • HCC 19 — Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers [CMS-HCC]: “Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers — supersedes HCC 20 (Lung and Other Severe Cancers), HCC 21 (Lymphoma and Other Cancers), HCC 22 (Bladder, Colorectal, and Other Cancers), HCC 23 (Prostate, Breast, and Other Cancers and Tumors)”— CMS-HCC V28 · 2026

MS-DRG Grouper

MDC crossing

  • MDC 16 — Diseases and Disorders of Blood, Blood Forming Organs and Immunologic Disorders[MDC crossing]: “Diseases and Disorders of Blood, Blood Forming Organs and Immunologic Disorders — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 1,614 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

  • Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), refractory[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (12)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
Risk adjustment Official source data
2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Refractory anemia, unspecified

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to D46.4 in its code family, with their registry titles.

View all codes in the D46 family