Chapter 4: Diseases of the Immune System
ICD-11 codes 4A00-4B4Z
A new chapter in ICD-11 covering primary immunodeficiencies, autoimmune diseases, allergic and hypersensitivity conditions, and immune system disorders. This was separated from blood diseases to reflect modern understanding of immunology.
4A00-4A0Z
Primary immunodeficiencies
4A40-4A4Z
Nonorgan specific systemic autoimmune disorders
4A40Lupus erythematosus
4A41Idiopathic inflammatory myopathy
4A42Systemic sclerosis
4A43Overlap or undifferentiated nonorgan specific systemic autoimmune disease
4A44Vasculitis
4A45Antiphospholipid syndrome
4A4YOther specified nonorgan specific systemic autoimmune disorders
4A4ZNonorgan specific systemic autoimmune disorders, unspecified
4A60-4A6Z
Autoinflammatory disorders
4A80-4A8Z
Allergic or hypersensitivity conditions
4A80Allergic or hypersensitivity disorders involving the respiratory tract
4A81Allergic or hypersensitivity disorders involving the eye
4A82Allergic or hypersensitivity disorders involving skin or mucous membranes
4A83Allergic or hypersensitivity disorders involving the gastrointestinal tract
4A84Anaphylaxis
4A85Complex allergic or hypersensitivity conditions
4A8YAllergic or hypersensitivity conditions of other specified type
4A8ZAllergic or hypersensitivity conditions of unspecified type
4B00-4B0Z
Immune system disorders involving white cell lineages
4B00Disorders of neutrophil number
4B01Disorders of neutrophil function
4B02Eosinopenia
4B03Eosinophilia
4B04Disorders with decreased monocyte counts
4B05Disorders with increased monocyte counts
4B06Acquired lymphopenia
4B07Acquired lymphocytosis
4B0YOther specified immune system disorders involving white cell lineages
4B0ZImmune system disorders involving white cell lineages, unspecified
4B20-4B2Y
Certain disorders involving the immune system
Frequently Asked Questions
What ICD-11 codes are in Chapter 4?
Chapter 4: Diseases of the Immune System covers ICD-11 codes 4A00-4B4Z. It contains 6 code blocks with 41 top-level categories.
What conditions does ICD-11 Chapter 4 cover?
A new chapter in ICD-11 covering primary immunodeficiencies, autoimmune diseases, allergic and hypersensitivity conditions, and immune system disorders. This was separated from blood diseases to reflect modern understanding of immunology. This chapter includes codes from 4A00-4B4Z.
How is ICD-11 Chapter 4 different from ICD-10?
ICD-11 reorganized many chapters compared to ICD-10. Chapter 4 (Diseases of the Immune System) may include conditions that were in different ICD-10 chapters, and some conditions previously here may have moved. ICD-11 also adds new chapters for sleep-wake disorders, sexual health, and traditional medicine that did not exist in ICD-10.
How many code blocks are in ICD-11 Chapter 4?
Chapter 4 has 6 code blocks: 4A00-4A0Z (Primary immunodeficiencies), 4A40-4A4Z (Nonorgan specific systemic autoimmune disorders), 4A60-4A6Z (Autoinflammatory disorders), 4A80-4A8Z (Allergic or hypersensitivity conditions), and 2 more.
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