Thalassemia (D56) ICD-10-CM
The D56 code range covers thalassemia with 9 ICD-10-CM diagnosis codes. 8 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- sickle-cell thalassemia D57.4
Codes in the D56 Range 9 codes · 8 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the D56 range.
alpha-Thalassemia
A disorder characterized by reduced synthesis of the alpha chains of hemoglobin. The severity of this condition can vary from mild anemia to death, depending on the number of genes deleted.
beta-Thalassemia
A disorder characterized by reduced synthesis of the beta chains of hemoglobin. There is retardation of hemoglobin A synthesis in the heterozygous form (thalassemia minor), which is asymptomatic, while in the homozygous form (thalassemia major, Cooley's anemia, Mediterranean anemia, erythroblastic anemia), which can result in severe complications and even death, hemoglobin A synthesis is absent.
Hemoglobin C Disease
A disease characterized by compensated hemolysis with a normal hemoglobin level or a mild to moderate anemia. There may be intermittent abdominal discomfort, splenomegaly, and slight jaundice.
Hydrops Fetalis
Abnormal accumulation of serous fluid in two or more fetal compartments, such as SKIN; PLEURA; PERICARDIUM; PLACENTA; PERITONEUM; AMNIOTIC FLUID. General fetal EDEMA may be of non-immunologic origin, or of immunologic origin as in the case of ERYTHROBLASTOSIS FETALIS.
Thalassemia
A group of hereditary hemolytic anemias in which there is decreased synthesis of one or more hemoglobin polypeptide chains. There are several genetic types with clinical pictures ranging from barely detectable hematologic abnormality to severe and fatal anemia.
About the D56 Code Range
ICD-10 code D56 represents thalassemia, a group of inherited blood disorders affecting hemoglobin production. This section is used for coding various types of thalassemia, including alpha, beta, delta-beta forms, and related conditions.
The ICD-10 code for alpha thalassemia (D56.0) covers conditions like Hemoglobin H disease and Hydrops fetalis, often tagged as hemolytic anemia. It includes multiple syndromes such as Hemoglobin Paksé and Alpha zero thalassemia. The beta thalassemia code (D56.1) addresses beta globin chain defects causing anemia and is also linked with sickle cell-thalassemia variants and hereditary persistence of fetal hemoglobin. Delta-beta thalassemia (D56.2) and thalassemia minor (D56.3) capture other genetic variations and mild forms. Codes D56.4 through D56.8 identify specific hemoglobinopathies like Hereditary persistence of fetal hemoglobin, Hemoglobin E-beta thalassemia, and other rare thalassemias combining with hemoglobin C or D diseases. The unspecified code D56.9 applies when detailed classification is unavailable but thalassemia complicates pregnancy or childbirth. These codes help clinicians and coders accurately document the diverse clinical presentations of thalassemia.
Questions About This Page
How many billable codes are in the D56 range?
Of the 9 codes in this range, 8 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the D56 range classify?
The range classifies thalassemia. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
