ICD-10-CM 2027
ICD-10 code for thrombocytosis
From the official ICD-10-CM alphabetic index entry “Thrombocytosis”. Page updated September 29, 2026.
About coding thrombocytosis
The ICD-10-CM code for thrombocytosis is D75.839 (Thrombocytosis, unspecified). The official index lists 6 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on D75.839.
Within D75.83, choose D75.839 (unspecified) only when documentation doesn't support a more specific option: other thrombocytosis (D75.838).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
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 thrombocytosis codes (official index)
Common questions about thrombocytosis ICD-10 codes
What is the ICD-10 code for thrombocytosis?
- D75.839 — Thrombocytosis, unspecified. More specific codes apply when the documentation supports them: D47.3, D47.3, D47.3, D75.838 and others below.
What is the ICD-10 code for essential thrombocytosis?
- D47.3 — Essential (hemorrhagic) thrombocythemia.
What is the ICD-10 code for idiopathic thrombocytosis?
- D47.3 — Essential (hemorrhagic) thrombocythemia.
What is the ICD-10 code for primary thrombocytosis?
- D47.3 — Essential (hemorrhagic) thrombocythemia.
What is the ICD-10 code for reactive thrombocytosis?
- D75.838 — Other thrombocytosis.
What is the ICD-10 code for secondary thrombocytosis?
- D75.838 — Other thrombocytosis.
Is D75.839 billable?
- Yes. D75.839 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D75.839 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D75.839 as a principal diagnosis.
Is D75.839 a CC or MCC?
- No. D75.839 is neither a CC nor an MCC under MS-DRG v44.0.