D89.41 — Monoclonal mast cell activation syndrome
D89.41 is a billable, specific ICD-10-CM code for monoclonal mast cell activation syndrome. It is valid for submission on a claim.
Risk adjustment
D89.41 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
D89.41 is named in 15 Medicare coverage policies — 15 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56638Billing and Coding: Gastrointestinal Pathogen (GIP) Panels Utilizing Multiplex Nucleic Acid Amplification Techniques (NAATs)
- A56642Billing and Coding: Gastrointestinal Pathogen (GIP) Panels Utilizing Multiplex Nucleic Acid Amplification Techniques (NAATs)
- A57689Billing and Coding: Lab: Flow Cytometry
- A58575Billing and Coding: Respiratory Pathogen Panel Testing
How D89.41 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to D89.41.
- Activation›mast cell›monoclonal
Related codes at this level
Codes that share D89.4. If D89.41 is not quite right, the correct code is usually one of these.
Questions about D89.41
- Is D89.41 a billable ICD-10-CM code?
- Yes. D89.41 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does D89.41 sit in the tabular list?
- Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89), in the block Certain disorders involving the immune mechanism (D80-D89).