DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

D89 Other disorders involving the immune mechanism, not elsewhere classified

  • Header · not billable

D89 is not billable. The category heads 24 billable codes in FY2027, grouped under 7 subdivisions.

Index → code

  • Paraproteinemia → D89.2
  • Cryofibrinogenemia → D89.2
  • Hypergammaglobulinemia → D89.2

Where it sits

  1. Chapter 3 Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89)
  2. D80-D89 Certain disorders involving the immune mechanism (D80-D89)
  3. D89 Other disorders involving the immune mechanism, not elsewhere classified
Billable codes
24
Subdivisions
7
CC / MCC codes
7 / 0
HCC V28 codes
5
New FY2027
0
Index entries
58

Codes in D89

  1. D89.0
    Polyclonal hypergammaglobulinemia
    Billable
    Inclusion terms 2

    Inclusion terms

    • Benign hypergammaglobulinemic purpura
    • Polyclonal gammopathy NOS
  2. D89.1
    Cryoglobulinemia
    Billable
    Inclusion terms 7

    Inclusion terms

    • Cryoglobulinemic purpura
    • Cryoglobulinemic vasculitis
    • Essential cryoglobulinemia
    • Idiopathic cryoglobulinemia
    • Mixed cryoglobulinemia
    • Primary cryoglobulinemia
    • Secondary cryoglobulinemia
  3. D89.2
    Hypergammaglobulinemia, unspecified
    Billable
  4. D89.3
    Immune reconstitution syndrome
    Billable
    Inclusion terms 1, Use additional code 1

    Inclusion terms

    • Immune reconstitution inflammatory syndrome [IRIS]

    Use additional code

    • code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5) T36 T50
  5. D89.4
    Mast cell activation syndrome and related disorders
    Header
    Excludes1 11

    Excludes1

    • aggressive systemic mastocytosis (C96.21) C96.21
    • congenital cutaneous mastocytosis (Q82.2) Q82.2
    • (non-congenital) cutaneous mastocytosis (D47.01) D47.01
    • (indolent) systemic mastocytosis (D47.02) D47.02
    • malignant mast cell neoplasm (C96.2-) C96.2
    • malignant mastocytoma (C96.29) C96.29
    • mast cell leukemia (C94.3-) C94.3
    • mast cell sarcoma (C96.22) C96.22
    • mastocytoma NOS (D47.09) D47.09
    • other mast cell neoplasms of uncertain behavior (D47.09) D47.09
    • systemic mastocytosis associated with a clonal hematologic non-mast cell lineage disease (SM-AHNMD) (D47.02) D47.02
  6. D89.40
    Mast cell activation, unspecified
    Billable
    Inclusion terms 2

    Inclusion terms

    • Mast cell activation disorder, unspecified
    • Mast cell activation syndrome, NOS
  7. D89.41
    Monoclonal mast cell activation syndrome
    Billable
  8. D89.42
    Idiopathic mast cell activation syndrome
    Billable
  9. D89.43
    Secondary mast cell activation
    Billable
    Inclusion terms 1, Code also 1

    Inclusion terms

    • Secondary mast cell activation syndrome

    Code also

    • underlying etiology, if known
  10. D89.44
    Hereditary alpha tryptasemia
    Billable
    Use additional code 3

    Use additional code

    • code, if applicable, for:
    • allergy status, other than to drugs and biological substances (Z91.0-) Z91.0
    • personal history of anaphylaxis (Z87.892) Z87.892
  11. D89.49
    Other mast cell activation disorder
    Billable
    Inclusion terms 1

    Inclusion terms

    • Other mast cell activation syndrome
  12. D89.8
    Other specified disorders involving the immune mechanism, not elsewhere classified
    Header
  13. D89.81
    Graft-versus-host disease
    Header
    Code first 3, Use additional code 5

    Code first

    • underlying cause, such as:
    • complications of transplanted organs and tissue (T86.-) T86
    • complications of blood transfusion (T80.89) T80.89

    Use additional code

    • code to identify associated manifestations, such as:
    • desquamative dermatitis (L30.8) L30.8
    • diarrhea (R19.7) R19.7
    • elevated bilirubin (R17) R17
    • hair loss (L65.9) L65.9
  14. D89.810
    Acute graft-versus-host disease
    BillableCC454
  15. D89.811
    Chronic graft-versus-host disease
    BillableCC454
  16. D89.812
    Acute on chronic graft-versus-host disease
    BillableCC454
  17. D89.813
    Graft-versus-host disease, unspecified
    BillableCC454
  18. D89.82
    Autoimmune lymphoproliferative syndrome [ALPS]
    Billable
  19. D89.83
    Cytokine release syndrome
    Header
    Code first 3, Use additional code 2

    Code first

    • underlying cause, such as:
    • complications following infusion, transfusion and therapeutic injection (T80.89-) T80.89
    • complications of transplanted organs and tissue (T86.-) T86

    Use additional code

    • code for adverse effect, if applicable, to identify immune checkpoint inhibitors and immunostimulant drugs (T45.AX5) T45.AX5
    • code to identify associated manifestations
  20. D89.831
    Cytokine release syndrome, grade 1
    Billable
  21. D89.832
    Cytokine release syndrome, grade 2
    Billable
  22. D89.833
    Cytokine release syndrome, grade 3
    BillableCC
  23. D89.834
    Cytokine release syndrome, grade 4
    BillableCC
  24. D89.835
    Cytokine release syndrome, grade 5
    BillableCC
  25. D89.839
    Cytokine release syndrome, grade unspecified
    Billable
  26. D89.84
    IgG4-related disease
    Billable115
    Inclusion terms 1

    Inclusion terms

    • Immunoglobulin G4-related disease
  27. D89.89
    Other specified disorders involving the immune mechanism, not elsewhere classified
    Billable
    Excludes1 1

    Excludes1

    • human immunodeficiency virus disease (B20) B20
  28. D89.9
    Disorder involving the immune mechanism, unspecified
    Billable
    Inclusion terms 1

    Inclusion terms

    • Immune disease NOS

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

At D89

Excludes1

  • hyperglobulinemia NOS (R77.1) R77.1
  • monoclonal gammopathy (of undetermined significance) (D47.2) D47.2

Excludes2

  • transplant failure and rejection (T86.-) T86

Notes that also apply

Block D80-D89 instructions (Includes 3, Excludes1 2, Excludes2 1): printed on the block page.

Chapter 3 instructions (Excludes2 9): printed on the chapter 3 page.

Index entries

  • Cryoglobulinemia (essential) (idiopathic) (mixed) (primary) (purpura) (secondary) (vasculitis) → D89.1
  • Cryofibrinogenemia → D89.2
  • Hypergammaglobulinemia → D89.2
  • Paraproteinemia → D89.2
  • Immune reconstitution (inflammatory) syndrome [IRIS] → D89.3
  • Hereditary alpha tryptasemia (syndrome) → D89.44
  • Tryptasemia, hereditary alpha → D89.44
  • Graft-versus-host disease → D89.813
  • PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections syndrome) → D89.89
  • PANS (Pediatric Acute-onset Neuropsychiatric Syndrome) → D89.89
  • Gammopathy (of undetermined significance [MGUS])polyclonal → D89.0
  • Hypergammaglobulinemiapolyclonal → D89.0
  • HypergammaglobulinemiaWaldenström → D89.0
  • Purpurahypergammaglobulinemic (benign) (Waldenström) → D89.0
  • Waldenströmhypergammaglobulinemia → D89.0
  • Cryoglobulinemia (essential) (idiopathic) (mixed) (primary) (purpura) (secondary) (vasculitis)with lung involvement → D89.1 [J99]
  • Purpuracryoglobulinemic → D89.1
  • Vasculitiscryoglobulinemic → D89.1
  • Paraproteinemiabenign (familial) → D89.2
  • Syndromeimmune reconstitution → D89.3
  • Syndromeimmune reconstitution inflammatory [IRIS] → D89.3
  • Activationmast cell (disorder) (syndrome) → D89.40
  • Syndromehereditary alpha tryptasemia → D89.44
  • Graft-versus-host diseaseacute → D89.810
  • Graft-versus-host diseasechronic → D89.811
  • Graft-versus-host diseaseacute on chronic → D89.812
  • Disease, diseasedgraft-versus-host (GVH) → D89.813
  • Disease, diseasedhost-versus-graft → D89.813
  • Autoimmunelymphoproliferative syndrome [ALPS] → D89.82
  • Syndromeautoimmune lymphoproliferative [ALPS] → D89.82
  • Syndromecytokine release → D89.839
  • Disease, diseasedIgG4-related → D89.84
  • Disorder (of)autoimmune → D89.89
  • Syndromepediatric acute-onset neuropsychiatric (PANS) → D89.89
  • Syndromepediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) → D89.89
  • Disease, diseasedimmune → D89.9
  • Disorder (of)immune mechanism (immunity) → D89.9
  • Disorder (of)glomerular (in)cryoglobulinemia → D89.1 [N08]
  • Disorder (of)tubulo-interstitial (in)mixed cryoglobulinemia → D89.1 [N16]
  • Glomerulonephritisin (due to)cryoglobulinemia → D89.1 [N08]

18 more, longer entries are not listed; the search box finds them by word.

NCHS Alphabetic Index. Index first, then the Tabular List.

Hierarchy