Aggressive systemic mastocytosis

This code represents a rare and severe form of mastocytosis characterized by the abnormal proliferation and accumulation of mast cells in various organs, leading to organ damage and dysfunction. It is distinguished from other forms of mastocytosis by its aggressive clinical course and involvement of non-cutaneous tissues.

This code is appropriate for patients diagnosed with aggressive systemic mastocytosis, often confirmed by bone marrow biopsy showing dense mast cell infiltrates and evidence of organ damage. Documentation should clearly specify the aggressive nature of the disease and systemic involvement, differentiating it from indolent or cutaneous forms.

• Differentiate from other mastocytosis codes (e.g., C96.20, C96.29) based on the specific type and aggressiveness.
• Ensure documentation supports systemic involvement and organ damage, not just cutaneous manifestations.
• Consider sequencing with codes for associated organ dysfunction or complications.