Term
| Autoimmune hemolytic anemia |
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Definition
Type II Hypersensitivity
Target Antigen: Red cell membrane proteins (Rh blood group antigens, I antigen)
Mechanisms of Disease: Opsonization and phagocytosis of red cells
Clinicopathologic Manifestations: Hemolysis, anemia |
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Term
| Autoimmune thrombocytopenic purpura |
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Definition
Type II Hypersensitivity
Target Antigen: Platelet membrane proteins (Gpllb: Illa integrin)
Mechanisms of Disease: Opsonization and phagocytosis of platelets
Clinicopathologic Manifestations: Bleeding |
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Term
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Definition
Type II Hypersensitivity
Target Antigen: Proteins in intercellular junctions of epidermal cells (epidermal cadherin)
Mechanisms of Disease: Antibody-mediated activation of proteases, disruption of intercellular adhesions
Clinicopathologic Manifestations: Skin vesicles (bullae) |
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Term
| Vasculitis caused by ANCA |
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Definition
Type II Hypersensitivity
Target Antigen: Neutrophil granule proteins, presumably released from activated neutrophils
Mechanisms of Disease: Neutrophil degranulation and inflammation
Clinicopathologic Manifestations: Vasculitis |
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Term
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Definition
Type II Hypersensitivity
Target Antigen: Noncollagenous protein in basement membranes of kidney glomeruli and lung alveoli
Mechanisms of Disease: Complement- and Fc receptorÐmediated inflammation
Clinicopathologic Manifestations: Nephritis, lung hemorrhage |
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Term
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Definition
Type II Hypersensitivity
Target Antigen: Streptococcal cell wall antigen; antibody cross-reacts with myocardial antigen
Mechanisms of Disease: Inflammation, macrophage activation
Clinicopathologic Manifestations: Myocarditis, arthritis |
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Term
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Definition
Type II Hypersensitivity
Target Antigen: Acetylcholine receptor
Mechanisms of Disease: Antibody inhibits acetylcholine binding, down-modulates receptors
Clinicopathologic Manifestations: Muscle weakness, paralysis |
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Term
| Graves disease (hyperthyroidism) |
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Definition
Type II Hypersensitivity
Target Antigen: TSH receptor
Mechanisms of Disease: Antibody-mediated stimulation of TSH receptors
Clinicopathologic Manifestations: Hyperthyroidism |
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Term
| Insulin-resistant diabetes |
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Definition
Type II Hypersensitivity
Target Antigen: Insulin receptor
Mechanisms of Disease: Antibody inhibits binding of insulin
Clinicopathologic Manifestations: Hyperglycemia, ketoacidosis |
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Term
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Definition
Type II Hypersensitivity
Target Antigen: Intrinsic factor of gastric parietal cells
Mechanisms of Disease: Neutralization of intrinsic factor, decreased absorption of vitamin B12
Clinicopathologic Manifestations: Abnormal erythropoiesis, anemia |
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Term
| Systemic lupus erythematosus |
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Definition
Type III Hypersensitivity
Antigen Involved: Nuclear antigens
Clinicopathologic Manifestations: Nephritis, skin lesions, arthritis, others |
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Term
| Poststreptococcal glomerulonephritis |
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Definition
Type III Hypersensitivity
Antigen Involved: Streptococcal cell wall antigen(s); may be ÒplantedÓ in glomerular basement membrane
Clinicopathologic Manifestations: Nephritis |
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Term
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Definition
Type III Hypersensitivity
Antigen Involved: Hepatitis B virus antigens in some cases
Clinicopathologic Manifestations: Systemic vasculitis |
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Term
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Definition
Type III Hypersensitivity
Antigen Involved: Bacterial antigens (e.g., Yersinia)
Clinicopathologic Manifestations: Acute arthritis |
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Term
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Definition
Type III Hypersensitivity
Antigen Involved: Various proteins, e.g., foreign serum protein (horse anti-thymocyte globulin)
Clinicopathologic Manifestations: Arthritis, vasculitis, nephritis |
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Term
| Arthus reaction (experimental) |
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Definition
Type III Hypersensitivity
Antigen Involved: Various foreign proteins
Clinicopathologic Manifestations: Cutaneous vasculitis |
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Term
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Definition
Type IV Hypersensitivity
Specificity of Pathogenic T Cells Clinicopathologic: Antigens of pancreatic islet _ cells (insulin, glutamic acid decarboxylase, others)
Manifestations: Insulitis (chronic inflammation in islets), destruction of _ cells; diabetes |
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Term
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Definition
Type IV Hypersensitivity
Specificity of Pathogenic T Cells Clinicopathologic: Protein antigens in CNS myelin (myelin basic protein, proteolipid protein)
Manifestations: Demyelination in CNS with perivascular inflammation; paralysis, ocular lesions |
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Term
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Definition
Type IV Hypersensitivity
Specificity of Pathogenic T Cells Clinicopathologic: Unknown antigen in joint synovium (type II collagen?); role of antibodies?
Manifestations: Chronic arthritis with inflammation, destruction of articular cartilage and bone |
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Term
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Definition
Type IV Hypersensitivity
Specificity of Pathogenic T Cells Clinicopathologic: Unknown antigen; role for commensal bacteria
Manifestations: Chronic intestinal inflammation, obstruction |
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Term
| Peripheral neuropathy; Guillain-Barr syndrome? |
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Definition
Type IV Hypersensitivity
Specificity of Pathogenic T Cells Clinicopathologic: Protein antigens of peripheral nerve myelin
Manifestations: Neuritis, paralysis |
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Term
| Contact sensitivity (dermatitis) |
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Definition
Type IV Hypersensitivity
Specificity of Pathogenic T Cells Clinicopathologic: Various environmental antigens (e.g., poison ivy)
Manifestations: Skin inflammation with blisters |
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