D89.4
Header — not billableMast cell activation syndrome and related disorders
The ICD-10 code for mast cell activation syndrome and related disorders is D89.4.
D89.4 is a non-billable header code. It groups related conditions but cannot be used on its own for reimbursement — select one of the 6 more specific codes below.
Clinical notes
Excludes1 (not coded here)
An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).
- aggressive systemic mastocytosis (C96.21)
- congenital cutaneous mastocytosis (Q82.2)
- (non-congenital) cutaneous mastocytosis (D47.01)
- (indolent) systemic mastocytosis (D47.02)
- malignant mast cell neoplasm (C96.2-)
- malignant mastocytoma (C96.29)
- mast cell leukemia (C94.3-)
- mast cell sarcoma (C96.22)
- mastocytoma NOS (D47.09)
- other mast cell neoplasms of uncertain behavior (D47.09)
- systemic mastocytosis associated with a clonal hematologic non-mast cell lineage disease (SM-AHNMD) (D47.02)
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This is a non-billable header code. Documentation must support a more specific child code before this diagnosis can be reported on a claim.
- •Confirm the excluded condition(s) listed above are not also present — Excludes1 conditions cannot be coded together with this one.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
- D89.0Polyclonal hypergammaglobulinemia
- D89.1Cryoglobulinemia
- D89.2Hypergammaglobulinemia, unspecified
- D89.3Immune reconstitution syndrome
- D89.8Other specified disorders involving the immune mechanism, not elsewhere classifiednon-billable header
- D89.9Disorder involving the immune mechanism, unspecified
- D89.4Mast cell activation syndrome and related disordersnon-billable header