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D56.9 ICD-10-CM Code: Thalassemia, unspecified

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

Coding at a Glance

Tabular directives
1 inclusion term · 1 Excludes1

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 791 — PREMATURITY WITH MAJOR PROBLEMS (MDC 15)
  • MS-DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)
  • 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.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for D56.9 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 D56.9 itself; “inherited from” names the category or block whose note applies here.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Mediterranean anemia (with other hemoglobinopathy)

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 D56

Coder workflow for D56.9

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

Before you code D56.9

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, D56.9 may be the appropriate code. Check the record for detail that supports a more specific sibling. 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).

    ReviewD56.0, D56.1, D56.2, D56.3, D56.4, D56.5, D56.8

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

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with D56.9. 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 — D56.9 is appropriate when the documentation goes no further.

    ReviewD56.0, D56.1, D56.2, D56.3, D56.4, D56.5, D56.8

  2. Does the documentation support a condition named in D56.9’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.

    ReviewD57.4

Consider D56.9. Then 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).
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 D56.9(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with D56.9: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareD57.4

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

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).

ReviewD56.0, D56.1, D56.2, D56.3, D56.4, D56.5, D56.8

Documentation: Both the condition D56.9 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).

ReviewD57.4

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

Thalassemia, unspecified is a billable ICD-10-CM diagnosis code (D56.9).

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 (12)

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.

Official Coding Guidelines

No excerpt in the ICD-10-CM Official Guidelines names this code specifically. Its chapter carries only this chapter-wide note:

Chapter 3: Disease of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89)

Reserved for future guideline expansion

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 D56.9 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 14 Excludes1 notes across 2 chapters: P50 — Newborn affected by intrauterine (fetal) blood loss (via D56.-), P50-P61 — Hemorrhagic and hematological disorders of newborn (P50-P61) (via D56.-), P51 — Umbilical hemorrhage of newborn (via D56.-), P52 — Intracranial nontraumatic hemorrhage of newborn (via D56.-), P53 — Hemorrhagic disease of newborn (via D56.-), P54 — Other neonatal hemorrhages (via D56.-), P55 — Hemolytic disease of newborn (via D56.-), P56 — Hydrops fetalis due to hemolytic disease (via D56.-), P57 — Kernicterus (via D56.-), P58 — Neonatal jaundice due to other excessive hemolysis (via D56.-), P59 — Neonatal jaundice from other and unspecified causes (via D56.-), P60 — Disseminated intravascular coagulation of newborn (via D56.-), P61 — Other perinatal hematological disorders (via D56.-), R71 — Abnormality of red blood cells (via D56.-).

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

Referenced by 24 Code First instructions across 3 chapters: I21.A1 — Myocardial infarction type 2 (via D56.-), M36.3 — Arthropathy in other blood disorders (via D56.-), M90.5 — Osteonecrosis in diseases classified elsewhere (via D56.-), T36 — Poisoning by, adverse effect of and underdosing of systemic antibiotics (via D56.-), T36-T39 — Antibiotics & Anti-infectives (T36-T39) (via D56.-), T36-T50 — Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50) (via D56.-), T37 — Poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics (via D56.-), T38 — Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified (via D56.-), T39 — Poisoning by, adverse effect of and underdosing of nonopioid analgesics, antipyretics and antirheumatics (via D56.-), T40 — Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens] (via D56.-), T40-T41 — Analgesics & Antipyretics (T40-T41) (via D56.-), T41 — Poisoning by, adverse effect of and underdosing of anesthetics and therapeutic gases (via D56.-), T42 — Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs (via D56.-), T42-T43 — Anticonvulsants & Psychotropics (T42-T43) (via D56.-), T43 — Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified (via D56.-), T44 — Poisoning by, adverse effect of and underdosing of drugs primarily affecting the autonomic nervous system (via D56.-), T44-T46 — Cardiovascular & Gastrointestinal (T44-T46) (via D56.-), T45 — Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified (via D56.-), T46 — Poisoning by, adverse effect of and underdosing of agents primarily affecting the cardiovascular system (via D56.-), T47 — Poisoning by, adverse effect of and underdosing of agents primarily affecting the gastrointestinal system (via D56.-), +4 more.

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

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 4 MS-DRGs: DRG 791 (MDC 15), DRG 793 (MDC 15), 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):BLD002 — Hemolytic anemia (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 clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Hemolytic anemia).

D55.3 — Anemia due to disorders of nucleotide metabolism, D55.8 — Other anemias due to enzyme disorders, D55.9 — Anemia due to enzyme disorder, unspecified, D56.0 — Alpha thalassemia, D56.1 — Beta thalassemia, D56.2 — Delta-beta thalassemia, D56.3 — Thalassemia minor, D56.4 — Hereditary persistence of fetal hemoglobin [HPFH], D56.5 — Hemoglobin E-beta thalassemia, D56.8 — Other thalassemias, D58.0 — Hereditary spherocytosis, D58.1 — Hereditary elliptocytosis, D58.2 — Other hemoglobinopathies, D58.8 — Other specified hereditary hemolytic anemias, D58.9 — Hereditary hemolytic anemia, unspecified, D59.0 — Drug-induced autoimmune hemolytic anemia, D59.1 — Other autoimmune hemolytic anemias, D59.10 — Autoimmune hemolytic anemia, unspecified, D59.11 — Warm autoimmune hemolytic anemia, D59.12 — Cold autoimmune hemolytic anemia, +18 more

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.

D53.2 — Scorbutic anemia (scorbutic), D53.8 — Other specified nutritional anemias (due to, deficiency, zinc), D53.9 — Nutritional anemia, unspecified (macrocytic), D55.0 — Anemia due to glucose-6-phosphate dehydrogenase [G6PD] deficiency (favism), D55.1 — Anemia due to other disorders of glutathione metabolism (deficiency, G SH), D55.21 — Anemia due to pyruvate kinase deficiency (deficiency, PK), D55.29 — Anemia due to other disorders of glycolytic enzymes (deficiency, 2, 3 PG), D55.3 — Anemia due to disorders of nucleotide metabolism (deficiency, enzyme, nucleotide metabolism), D55.8 — Other anemias due to enzyme disorders (deficiency, enzyme, specified type NEC), D55.9 — Anemia due to enzyme disorder, unspecified (deficiency, enzyme), D57.1 — Sickle-cell disease without crisis (Herrick's), D57.40 — Sickle-cell thalassemia without crisis (microdrepanocytosis), D58.0 — Hereditary spherocytosis (congenital, spherocytic), D58.2 — Other hemoglobinopathies (congenital, Heinz body), D58.8 — Other specified hereditary hemolytic anemias (stomatocytosis), D58.9 — Hereditary hemolytic anemia, unspecified (childhood), D59.0 — Drug-induced autoimmune hemolytic anemia (hemolytic, autoimmune, drug-induced), D59.10 — Autoimmune hemolytic anemia, unspecified (hemolytic, autoimmune), D59.11 — Warm autoimmune hemolytic anemia (hemolytic, warm type), D59.12 — Cold autoimmune hemolytic anemia (hemolytic, cold type), +284 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.

Iron Panel

Contextual Map

Every relationship of D56.9 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 D56.9 with these 16 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes (14)

Referenced by Code First instructions (24)

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

Index entries (12)

  • Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), Mediterranean (with other hemoglobinopathy)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), microelliptopoikilocytic (Rietti-Greppi- Micheli)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), Rietti-Greppi-Micheli[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), thalassemia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Arthritis, arthritic (acute) (chronic) (nonpyogenic) (subacute), in (due to), thalassemia NEC[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Disease, diseased, hemoglobin or Hb, abnormal NEC (mixed), with thalassemia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Disease, diseased, hemoglobin or Hb, H (Hb-H) (thalassemia), with other abnormal hemoglobin NEC[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Disease, diseased, hemoglobin or Hb, I thalassemia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • and 4 more

Nearest codes

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
Coding guidelines Official source data
ICD-10-CM Official Guidelines for Coding and Reporting (FY2026), quoted by section 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
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

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "D56.9 — Thalassemia, unspecified." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/d56.9-thalassemia-unspecified

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Thalassemia, 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 D56.9 in its code family, with their registry titles.

View all codes in the D56 family