ICD-10-CM 2027 diagnosis code
D55.21Anemia due to pyruvate kinase deficiency
D55.21 is a valid, billable ICD-10-CM code for anemia due to pyruvate kinase deficiency. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code last changed in FY2022 (effective October 1, 2021). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About D55.21
D55.21 is the ICD-10-CM diagnosis code for anemia due to pyruvate kinase deficiency. It belongs to category D55 (anemia due to enzyme disorders), block D55-D59 (hemolytic anemias) and chapter 3 (diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within D55.2 (anemia due to disorders of glycolytic enzymes), D55.21 is specifically for anemia due to pyruvate kinase deficiency. Related codes cover other disorders of glycolytic enzymes (D55.29).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 811 (Red Blood Cell Disorders with MCC, relative weight 1.3988) and DRG 812 (Red Blood Cell Disorders without MCC, relative weight 0.9234), in MDC 16 (Diseases and Disorders of the Blood and Blood Forming Organs and Immunological Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It was added in FY2022, effective October 1, 2021.
Coding notes
- PK deficiency anemia
- Pyruvate kinase deficiency anemia
Notes that apply from higher levels
Instructions written at a parent level also apply to D55.21.
› From D55.2 Anemia due to disorders of glycolytic enzymes
- disorders of glycolysis not associated with anemia (E74.81-)
› From D55 Anemia due to enzyme disorders
- drug-induced enzyme deficiency anemia (D59.2)
Broader instructions also apply from Chapter 3: Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism.
Alphabetic index entries
4 entriesTerms in the official ICD-10-CM index that lead to D55.21.
- Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound) › deficiency › PK
- Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound) › deficiency › pyruvate kinase
- Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound) › hemolytic › nonspherocytic › congenital or hereditary NEC › pyruvate kinase deficiency
- Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound) › pyruvate kinase deficiency
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 16 · Diseases and Disorders of the Blood and Blood Forming Organs and Immunological Disorders
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2022 (effective 10/1/2021): Added
- No changes since FY2022.
Common questions about D55.21
Is D55.21 billable?
- Yes. D55.21 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D55.21 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D55.21 as a principal diagnosis.
Is D55.21 a CC or MCC?
- No. D55.21 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does D55.21 group to?
- D55.21 is used in the MS-DRG v44.0 logic for MS-DRG 811 (Red Blood Cell Disorders with MCC) and MS-DRG 812 (Red Blood Cell Disorders without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.