D89: Other disorders involving the immune mechanism, not elsewhere classified

Codes under D89 (Other disorders involving the immune mechanism, not elsewhere classified). A ✓ marks a billable (fully specified) code; category codes without a ✓ are not billable on their own.

Code	Description	Billable
D89.0	Polyclonal hypergammaglobulinemia	✓
D89.1	Cryoglobulinemia	✓
D89.2	Hypergammaglobulinemia, unspecified	✓
D89.3	Immune reconstitution syndrome	✓
D89.4	Mast cell activation syndrome and related disorders	—
D89.8	Other specified disorders involving the immune mechanism, not elsewhere classified	—
D89.9	Disorder involving the immune mechanism, unspecified	✓
D89.40	Mast cell activation, unspecified	✓
D89.41	Monoclonal mast cell activation syndrome	✓
D89.42	Idiopathic mast cell activation syndrome	✓
D89.43	Secondary mast cell activation	✓
D89.44	Hereditary alpha tryptasemia	✓
D89.49	Other mast cell activation disorder	✓
D89.81	Graft-versus-host disease	—
D89.82	Autoimmune lymphoproliferative syndrome [ALPS]	✓
D89.83	Cytokine release syndrome	—
D89.84	IgG4-related disease	✓
D89.89	Other specified disorders involving the immune mechanism, not elsewhere classified	✓
D89.810	Acute graft-versus-host disease	✓
D89.811	Chronic graft-versus-host disease	✓
D89.812	Acute on chronic graft-versus-host disease	✓
D89.813	Graft-versus-host disease, unspecified	✓
D89.831	Cytokine release syndrome, grade 1	✓
D89.832	Cytokine release syndrome, grade 2	✓
D89.833	Cytokine release syndrome, grade 3	✓
D89.834	Cytokine release syndrome, grade 4	✓
D89.835	Cytokine release syndrome, grade 5	✓
D89.839	Cytokine release syndrome, grade unspecified	✓

More free billing tools: all ICD-10 categories · ICD-10 search · denial codes · Medicare fees

Informational only, not coding or medical advice. Verify against the official ICD-10-CM (FY2026) and your payer's guidelines.

Code the diagnosis right