Exam 5 Full Study Guide Flashcards
Define Hypersensitivity
An exaggerated immune response to a typically harmless antigen
What are the Four Categories of Hypersensitivity?
Type I, Type II, Type III, Type IV.
Compare Immediate vs. Delayed Hypersensitivity Reactions
Immediate occurs within minutes to hours; Delayed occurs 48-72 hours after exposure.
What mediates Type I Hypersensitivity?
IgE, Histamine, Heparin; mediated by Mast cells and Basophils.
What are the 3 phases of Type I Hypersensitivity?
Sensitization, Activation, Effector Phases.
Common allergens associated with Type I Hypersensitivity
Food allergies, Rhinitis, Asthma, Urticaria (“hives”) wheal-and-flare reaction, systemic anaphylaxis.
What is Anaphylaxis?
A severe and most immediate hypersensitivity, potentially life-threatening allergic reaction.
What treatments are available for Type I Hypersensitivity?
Antihistamines, Epinephrine pens, Allergy shots (AIT), In vivo skin tests: evaluates the cellular immune response, and Monoclonal anti-IgE antibody.
What is RAST testing?
Radioallergosorbent test used to detect specific IgE antibodies.
What characterizes Type II Hypersensitivity?
Cytotoxic reactions against cell surface antigens; mediated by IgG and IgM.
What are common examples of Type II Hypersensitivity?
Transfusion reactions, Hemolytic disease of the newborn (HDN), Autoimmune hemolytic anemias.
What tests are used for Type II Hypersensitivity?
Indirect Antiglobulin Test (IAT); Coombs’ test and Direct Antiglobulin Test (DAT).
What defines Type III Hypersensitivity?
Immune complex-mediated hypersensitivity, small antigen-antibody complexes precipitate out and deposit in tissue
Examples of diseases associated with Type III Hypersensitivity
Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA), Glomerulonephritis.
What are common tests for Type III Hypersensitivity?
Rheumatoid Factor (RF), Complement levels, Antinuclear Antibody (ANA) testing.
What is Type IV Hypersensitivity?
Delayed-type hypersensitivity mediated by T-cells. Hypersensitivity peaks 48 to 72 hours after antigen exposure
What are common examples of Type IV Hypersensitivity?
Contact (dermatitis) allergies- poison ivy, poision oak, nickel salts, materials in cosmetics and hair dyes, latex
Infections with intracellular pathogens- tuberculosis and herpes simplex virus
Tuberculin skin test (Mantoux test).
What does a positive PPD test indicate?
Exposure to M. tuberculosis.
Define Autoimmune Disease and Autoantibody
A condition where the immune system attacks the body’s own tissues.
Antibody produced against an antigen found in an individual’s own cells, tissues, or organs
What are ANAs?
Antinuclear antibodies that target substances within the nucleus of cells.
Includes: Anti-ds DNA (Lupus-specific) and Anti-Sm (Smith antigen) specific for SLE
What is the IIF test?
The most widely used, highly sensitive, inexpensive, wide range of Ab, easy to perform
It incubates patient serum with Hep-2 cells fixed onto a microscope slide
(Hep-2 cells are a human epithelial cell line; used because of their large nuclei)
It washes and incubates fluorescein- labeled anti-human IgG
What are the ANA patterns associated with SLE?
Homogeneous, Peripheral (Rim), and Fine/Coarse Speckled.
What is Rheumatoid Arthritis (RA)?
An autoimmune disease characterized by joint inflammation, chronic arthritis of peripheral joints that can progress to joint deformity and disability.
What antibodies are associated with RA?
Rheumatoid Factor (RF): IgM autoantibody directed against the Fc portion of IgG (capillary swelling, inflammation, deposits of immune complexes; initiates complement cascade) and Anti-Citrullinated Protein Antibodies (Anti-CCP).
What is Sjogren’s Syndrome?
An autoimmune condition affecting exocrine glands like the salivary and tear ducts, leading to dry eyes and mouth (sicca).
What antibodies are directed against in Sjogren’s Syndrome?
Anti-RNA antibodies, specifically anti-SS-A and anti-SS-B.
What is Scleroderma?
An autoimmune disease characterized by skin thickening and organ involvement.
Fibrosis and vasculitis affects the skin, joints, and other organs
What does CREST stand for?
Calcinosis, Raynaud’s phenomenon, Esophageal dysmotility, Sclerodactyly, Telangiectasia.
What is Hashimoto’s Thyroiditis?
An autoimmune disorder leading to hypothyroidism.
What are the lab findings in Hashimoto’s Thyroiditis?
Normal TSH and decreased Free T4.
What is Graves Disease?
An autoimmune disorder leading to hyperthyroidism.
What are the lab findings in Graves Disease?
Decreased TSH and increased Free T4.
What is Type I Diabetes?
An autoimmune condition characterized by hyperglycemia due to pancreatic islet cell destruction.
What triggers Celiac Disease?
Dietary gluten.
What antibodies are associated with Celiac Disease?
Antibodies against gliadin.
What is Multiple Sclerosis?
An autoimmune disease characterized by the destruction of myelin in the CNS.
What antibodies are tested for in Multiple Sclerosis?
Antibodies against myelin basic protein.
What defines Plasma Cell Dyscrasias?
Abnormal proliferation of plasma cells leading to various diseases.
What is Multiple Myeloma?
A malignancy of mature plasma cells characterized by excessive plasma cells in the bone marrow.
What does CRABS stand for in Multiple Myeloma?
Calcium elevation, Renal failure, Anemia, Bone lesions.
What are Bence Jones Proteins?
Monoclonal light chains found in urine in Multiple Myeloma.
What is Waldenstrom Macroglobulinemia?
A malignancy characterized by the proliferation of lymphoplasmacytic cells producing IgM.
What are the key markers for Waldenstrom Macroglobulinemia?
CD19 and CD22.
What is the primary immunoglobulin seen in Waldenstrom Macroglobulinemia?
IgM.
What is the main difference between Multiple Myeloma and Waldenstrom Macroglobulinemia?
Type of plasma cell malignancy; MM involves IgG, while Waldenstrom involves IgM.
