Code First Notes in Chapter 3: Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism ICD-10-CM
A Code First note means the underlying condition named in the note is sequenced before this code. In Chapter 3 (D50-D89), notes printed in the chapter name other codes 30 times, and Code First Notes anywhere in the Tabular List name the chapter’s codes 27 times, covering 20 distinct codes, categories and ranges. Switch views to read the list either way.
Code First Notes by the code that carries the note
- D59.39 Other hemolytic-uremic syndrome
- D61.2 Aplastic anemia due to other external agents
- D63.0 Anemia in neoplastic disease
- D63.1 Anemia in chronic kidney disease
- underlying chronic kidney disease (CKD) (N18.-)
- D63.8 Anemia in other chronic diseases classified elsewhere
- D64.2 Secondary sideroblastic anemia due to drugs and toxins
- D69.42 Congenital and hereditary thrombocytopenia purpura
- thrombocytopenia with absent radius (TAR syndrome) (Q87.2)
- D72.18 Eosinophilia in diseases classified elsewhere
- chronic myelomonocytic leukemia (C93.1-)
- D75.81 Myelofibrosis
- malignant neoplasm of breast (C50.-)
- D77 Other disorders of blood and blood-forming organs in diseases classified elsewhere
- D84.81 Immunodeficiency due to conditions classified elsewhere
- D50.0-D64.9 Iron deficiency anemia secondary to blood loss (chronic) to Anemia, unspecified 127 codes
- I21.A1 Myocardial infarction type 2: anemia (D50.0-D64.9)
- M90.5 Osteonecrosis in diseases classified elsewhere: hemoglobinopathy (D50-D64)
- D51.0 Vitamin B12 deficiency anemia due to intrinsic factor deficiency
- G32.0 Subacute combined degeneration of spinal cord in diseases classified elsewhere: vitamin B12 deficiency anemia due to intrinsic factor deficiency (D51.0)
- D51.3 Other dietary vitamin B12 deficiency anemia
- G32.0 Subacute combined degeneration of spinal cord in diseases classified elsewhere: other dietary vitamin B12 deficiency anemia (D51.3)
- D51.8 Other vitamin B12 deficiency anemias
- G32.0 Subacute combined degeneration of spinal cord in diseases classified elsewhere: vitamin B12 deficiency anemia, unspecified (D51.8)
- M36.3 Arthropathy in other blood disorders: thalassemia (D56.-)
- D56-D76 Thalassemia to Other specified diseases with participation of lymphoreticular and reticulohistiocytic tissue 202 codes
- Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances: blood disorders (D56-D76)
- N08 Glomerular disorders in diseases classified elsewhere: sickle-cell disease (D57.0-D57.8)
- D58.2 Other hemoglobinopathies
- M36.3 Arthropathy in other blood disorders: other hemoglobinopathies (D58.2)
- D65 Disseminated intravascular coagulation [defibrination syndrome]
- N08 Glomerular disorders in diseases classified elsewhere: disseminated intravascular coagulation (D65)
- D66 Hereditary factor VIII deficiency
- D67 Hereditary factor IX deficiency
- M36.2 Hemophilic arthropathy: with vascular defect (D68.0-)
- D68.1 Hereditary factor XI deficiency
- M36.2 Hemophilic arthropathy: hemophilia C (D68.1)
- D69.0 Allergic purpura
- M36.4 Arthropathy in hypersensitivity reactions classified elsewhere: Henoch (-Schönlein) purpura (D69.0)
- R50.81 Fever presenting with conditions classified elsewhere: neutropenia (D70.-)
- D75.9 Disease of blood and blood-forming organs, unspecified
- M36.3 Arthropathy in other blood disorders: disease of blood and blood-forming organs, unspecified (D75.9)
- M36.8 Systemic disorders of connective tissue in other diseases classified elsewhere: hypogammaglobulinemia (D80.-)
- J84.170 Interstitial lung disease with progressive fibrotic phenotype in diseases classified elsewhere: sarcoidosis (D86.-)
- D89.1 Cryoglobulinemia
The first view lists notes printed in this chapter (a note on a category or block applies to every code beneath it). The second lists codes of this chapter named by Code First Notes anywhere in the Tabular List, including notes in other chapters.
Questions About Code First Notes
What does a Code First note mean?
A Code First note means the underlying condition named in the note is sequenced before the code that carries the note. Under the etiology/manifestation convention, a “code first” note appears at the manifestation code and a “use additional code” note at the etiology code (Section I.A.13). The FY 2027 Tabular List has 810 of them; 600 name other codes, with 736 references to 429 distinct codes, categories and ranges.
Can a code with a Code First note be the principal diagnosis?
Not when it is a manifestation code. Codes titled “in diseases classified elsewhere” are never permitted as the first-listed or principal diagnosis; they must follow the underlying condition. The etiology and manifestation page lists them all.
Related References
Source: FY 2027 ICD-10-CM Tabular List (CMS and NCHS) and the ICD-10-CM Official Guidelines for Coding and Reporting FY 2027, Section I.A. ICD List is not affiliated with CMS or NCHS.