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  1. <Quick facts
    Quick Facts: Immune Disorders
    Allergic Reactions and Other Hypersensitivity Disorders
    • Anaphylactic Reactions
      • What are anaphylactic reactions?
      • What causes an anaphylactic reaction?
      • What are the symptoms of an anaphylactic reaction?
      • How can doctors tell if I have an anaphylactic reaction?
      • How do doctors treat anaphylactic reactions?
      • How can I prevent an anaphylactic reaction?
    • Angioedema
      • What is angioedema?
      • What causes angioedema?
      • What are the symptoms of angioedema?
      • How can doctors tell if I have angioedema?
      • How do doctors treat angioedema?
    • Autoimmune Diseases
      • What is an autoimmune disease?
      • What causes an autoimmune disease?
      • What are the symptoms of an autoimmune disease?
      • How can doctors tell if I have an autoimmune disease?
      • How do doctors treat an autoimmune disease?
    • Food Allergy
      • What is a food allergy?
      • What foods cause allergic reactions?
      • What are the symptoms of a food allergy?
      • How can doctors tell if I have a food allergy?
      • How do doctors treat a food allergy?
    • Seasonal Allergy
      • What are seasonal allergies?
      • What causes seasonal allergies?
      • What are the symptoms of seasonal allergies?
      • How can my doctor tell if I have seasonal allergies?
      • How do doctors treat symptoms from seasonal allergies?
    • Overview of Allergic Reactions
      • What is an allergic reaction?
      • What causes an allergic reaction?
      • What are the symptoms of an allergic reaction?
      • How do doctors tell if I have an allergic reaction?
      • How do doctors treat an allergic reaction?
      • How can I prevent allergic reactions?
    • Hereditary and Acquired C1 Inhibitor Deficiency
      • What are hereditary and acquired C1 inhibitor deficiency?
      • What causes hereditary or acquired angioedema?
        • What can trigger an attack of angioedema?
      • What are the symptoms of hereditary and acquired angioedema?
      • How can doctors tell if I have hereditary or acquired angioedema?
      • How do doctors treat hereditary and acquired angioedema?
        • Blocked airway treatment
    • Exercise-Induced Allergic Reactions
      • What are exercise-induced allergic reactions?
      • What happens during an exercise-induced allergic reaction?
      • How do doctors tell if I have an exercise-induced allergic reaction?
      • How do doctors treat exercise-induced allergic reactions?
    • Mastocytosis
      • What is mastocytosis?
      • What causes mastocytosis?
        • What can trigger an attack of mastocytosis?
      • What are the symptoms of mastocytosis?
      • How do doctors tell if I have mastocytosis?
      • How do doctors treat mastocytosis?
    • Year-Round Allergies
      • What are year-round allergies?
      • What causes year-round allergies?
      • What are the symptoms of year-round allergies?
      • How do doctors treat year-round allergies?
      • How can I prevent symptoms from year-round allergies?
    Biology of the Immune System
    • Overview of the Immune System
      • What is the immune system?
      • What does the immune system do?
      • What are the main parts of the immune system?
      • What problems can the immune system have?
    Immunodeficiency Disorders
    • Overview of Immunodeficiency Disorders
      • What is an immunodeficiency disorder?
      • What causes an immunodeficiency disorder?
      • What are the symptoms of an immunodeficiency disorder?
      • How can doctors tell if I have an immunodeficiency disorder?
      • How do doctors treat immunodeficiency disorders?
        • How do I prevent infections if I have immunodeficiency?
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