ICD-10-CM 2027 diagnosis code
D89.3Immune reconstitution syndrome
D89.3 is a valid, billable ICD-10-CM code for immune reconstitution syndrome. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Looking up by condition? See ICD-10 code for Immune reconstitution syndrome [IRIS].
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About D89.3
D89.3 is the ICD-10-CM diagnosis code for immune reconstitution syndrome. It belongs to category D89 (other disorders involving the immune mechanism, not elsewhere classified), block D80-D89 (certain disorders involving the immune mechanism) 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 D89 (other disorders involving the immune mechanism, not elsewhere classified), D89.3 is specifically for immune reconstitution syndrome. Related codes cover Polyclonal hypergammaglobulinemia (D89.0), Cryoglobulinemia (D89.1), hypergammaglobulinemia, unspecified (D89.2), mast cell activation syndrome and related disorders (D89.4), other specified disorders involving the immune mechanism, not elsewhere classified (D89.8) and disorder involving the immune mechanism, unspecified (D89.9).
Use an additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5).
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 814 (Reticuloendothelial and Immunity Disorders with MCC, relative weight 2.0729), DRG 815 (Reticuloendothelial and Immunity Disorders with CC, relative weight 1.0444) and DRG 816 (Reticuloendothelial and Immunity Disorders without CC/MCC, relative weight 0.7381), 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 has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 279.8 (other specified disorders involving the immune mechanism).
Coding notes
Notes that apply from higher levels
Instructions written at a parent level also apply to D89.3.
Alphabetic index entries
3 entriesTerms in the official ICD-10-CM index that lead to D89.3.
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
ICD-9-CM equivalent
Converter →- 279.8Other specified disorders involving the immune mechanismapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about D89.3
Is D89.3 billable?
- Yes. D89.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D89.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D89.3 as a principal diagnosis.
Is D89.3 a CC or MCC?
- No. D89.3 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does D89.3 group to?
- D89.3 is used in the MS-DRG v44.0 logic for MS-DRG 814 (Reticuloendothelial and Immunity Disorders with MCC), MS-DRG 815 (Reticuloendothelial and Immunity Disorders with CC) and MS-DRG 816 (Reticuloendothelial and Immunity Disorders without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for D89.3?
- The CMS General Equivalence Mappings map D89.3 to ICD-9-CM 279.8.