ICD-10-CM 2027
ICD-10 code for Leptocytosis
From the official ICD-10-CM alphabetic index entry “Leptocytosis, hereditary”. Page updated September 29, 2026.
About coding Leptocytosis
The ICD-10-CM code for Leptocytosis is D56.9 (Thalassemia, unspecified).
Within D56, choose D56.9 (unspecified) only when documentation doesn't support a more specific option: alpha thalassemia (D56.0), beta thalassemia (D56.1), Delta-beta thalassemia (D56.2), minor (D56.3), hereditary persistence of fetal hemoglobin [HPFH] (D56.4), hemoglobin E-beta thalassemia (D56.5) and other thalassemias (D56.8).
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 791 (Prematurity with Major Problems, relative weight 4.1075), DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), DRG 811 (Red Blood Cell Disorders with MCC, relative weight 1.3988) and DRG 812 (Red Blood Cell Disorders without MCC, relative weight 0.9234), in MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period) and 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.
Common questions about Leptocytosis ICD-10 codes
What is the ICD-10 code for Leptocytosis?
- D56.9 — Thalassemia, unspecified.
Is D56.9 billable?
- Yes. D56.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D56.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D56.9 as a principal diagnosis.
Is D56.9 a CC or MCC?
- No. D56.9 is neither a CC nor an MCC under MS-DRG v44.0.