ICD-10-CM 2027
ICD-10 code for Macrophage activation syndrome
From the official ICD-10-CM alphabetic index entry “Syndrome › macrophage activation”. Page updated September 29, 2026.
About coding Macrophage activation syndrome
The ICD-10-CM code for Macrophage activation syndrome is D76.1 (Hemophagocytic lymphohistiocytosis). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on D76.1.
Within D76 (other specified diseases with participation of lymphoreticular and reticulohistiocytic tissue), D76.1 is specifically for Hemophagocytic lymphohistiocytosis. Related codes cover Hemophagocytic syndrome, infection-associated (D76.2) and other histiocytosis syndromes (D76.3).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 814 (Reticuloendothelial and Immunity Disorders with MCC, relative weight 2.0729), DRG 815 (Reticuloendothelial and Immunity Disorders with CC, relative weight 1.0444) and DRG 816 (Reticuloendothelial and Immunity Disorders without CC/MCC, relative weight 0.7381), in MDC 16 (Diseases and Disorders of the Blood and Blood Forming Organs and Immunological Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific Macrophage activation syndrome codes (official index)
- due to infection D76.2 — Hemophagocytic syndrome, infection-associated
Common questions about Macrophage activation syndrome ICD-10 codes
What is the ICD-10 code for Macrophage activation syndrome?
- D76.1 — Hemophagocytic lymphohistiocytosis. More specific codes apply when the documentation supports them: D76.2.
Is D76.1 billable?
- Yes. D76.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D76.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D76.1 as a principal diagnosis.
Is D76.1 a CC or MCC?
- D76.1 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.