D89.43
Billable codeSecondary mast cell activation
The ICD-10 code for secondary mast cell activation is D89.43.
Clinical notes
Code also
Two codes may be needed to fully describe a condition, but unlike Code First/Use Additional Code, the sequencing order is not mandated by convention.
- underlying etiology, if known
Also known as
Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.
- Secondary mast cell activation syndrome
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 2798Approximate match
Associated MS-DRGs
D89.43 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.