| Term 
 | Definition 
 
        | antigen causing an allergic reaction |  | 
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        | Term 
 | Definition 
 
        | physician who specializes in testing for and treating allergies |  | 
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        | Term 
 | Definition 
 
        | hypersensitivity to a common substance |  | 
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        | Term 
 | Definition 
 
        | disease resulting from immune system attacking its own body is if a pathogen; examples include rheumatoid arthritis and systemic lupus erythematosus |  | 
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        | Term 
 | Definition 
 
        | appearance of wheals as part of allergic reaction |  | 
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        | Term 
 
        | Human immunodeficiency virus (HIV) |  | Definition 
 
        | virus that causes AID; known as a retrovirus |  | 
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        | Term 
 | Definition 
 
        | immune system that does not function properly; also called immunodeficiency disorder |  | 
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        | Term 
 | Definition 
 
        | antibodies; assist in protecting the body |  | 
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        | Term 
 | Definition 
 
        | branch of medicine concerned with treating immune system disorders |  | 
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        | Term 
 | Definition 
 
        | tissues’ response to injury; redness, pain, swelling, and feeling hot to touch |  | 
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        | Term 
 | Definition 
 
        | excessive tissue fluid due to blocked lymphatic flow |  | 
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        | Term 
 | Definition 
 
        | infection appearing in immunocompromised person |  | 
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        | Term 
 | Definition 
 
        | severe itching associated with hives |  | 
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