Exam 3- ch 55, 56, 57

immunocompetence

when the immune system responds appropriately to a foreign stimulus, the body’s integrity is maintained

-ability to mobilize and use it’s antibodies and other responses to stimulation by an antigen

immunoincompetence

when the immune system is too weak or too vigorous and homeostasis is disrupted causing a malfunction in the system

inappropriate immune responses

allergies, immunodeficiencies (AIDS), autoimmune disorders (thyroid disease, SLE, RA), attacks on benign foreign tissue

immunity

the quality of being insusceptible to or unaffected by a particular disease or condition- can be innate (natural) or adaptive (acquired)

innate immunity

provides physical, mechanical, and chemical barriers to invading pathogens and protects against the external environment

-intact skin, mucous membranes, cilia, stomach acid, tears, saliva, sebaceous glands, secretions and flora of the intestines and v*gina

adaptive immunity

provides a specific reaction to each invading antigen and has the unique ability to remember the antigen that caused the attack → produces antibodies

-thymus gland, spleen, bone marrow, blood and lymph

-specific immune response

innate cells and specificity

-cells: phagocytes, natural killer (NK) cells

-nonspecific- inflammatory response

adaptive cells and specifity

-cells: T and B cells

-specific

types of acquired immunity

-active- natural (exposure) and artificial (vaccine)

-passive- natural (from mother), artificial (injection of antibodies from another source)

humoral immunity

a form of immunity that responds to antigens- mediated by B cells

-B cells produce antibodies in response to antigen challenge upon first exposure

two system that activate from exposure to antigen

-complement: one of 25 complex serum proteins that together compose a system that breaks down bacteria and releases lysosomes to destroy bacteria

-antigen-antibody: results in mast cells releasing histamine which produces symptoms of allergy

allergen

substance that can produce a hypersensitivity reaction in the body but may not be inherently harmful

immunogen

any agent or substance capable of provoking an immune response or producing immunity

cellular immunity

mechanism of acquired immunity characterized by the dominant role of T cells

-once T cells have been sensitized, they are released into blood and tissue and attach to the organism and destroy it

ratio of T-helper cells to T-suppressor cells

2:1; when ratio is disrupted, autoimmune and immunodeficiency diseases occur

t-helper cells

coordinate immune response by activating phagocytes and other T cells, and by stimulating B cells to produce antibodies

negative effects of cellular immunity

rejection of transplanted tissues, contact hypersensitivity reactions, certain autoimmune diseases

four R’s of immune response

-recognize self from nonself

-respond to nonself invaders

-remember the invader

-regulate its actions

early signs of infection in the older adult

lethargy, fatigue, disorientation, irritability, loss of appetite

immunization

controlled exposure to a disease-producing pathogen develops antibodies while preventing disease

-vaccines are attenuated (weakened)

-vaccines stimulate humoral immunity- provides protection for months to years

immunotherapy

special treatment of allergic responses wherein the patient receives doses of offending allergens over a period of 1-3 years to develop immunity gradually (weekly tx)

-inject patient with very diluted antigen which patient had type I hypersensitivity response

Hypersensitivity disorders

excessive reaction to a particular stimulus- can be harmless such as pollens and foods

-believed to be caused by a genetic defect that allows increased production of IgE with release of histamine and other mediators from mast cells and basophils

-humoral reactions immediate, cellular reactions delayed

what does histamine release cauase?

vasodilation, edema, bronchoconstriction, mucus secretion, and pruritis

factors that influence hypersensitivity

-host response to allergen

-exposure amount

-nature of allergen

-route of allergen entry

-repeated exposure

anaphylaxis

sudden, severe vasodilation as a consequence of the release of certain chemical mediators from mast cells

-vasodilation causes increase in capillary permeability causing fluid to seep into the interstitial space from the vascular space

-s/s: decreased bp, laryngeal edema, and bronchospasm leading to cardiovascular collapse, MI, and respiratory failure

tx of anaphylaxis

-immediate, aggressive tx with epinephrine (bronchodilation and vasoconstriction)

-subq for mild and IV or IM for severe

-diphenhydramine 50-100 mg IM or IV

-IV therapy with volume expanders and vasopressor agents may be initiated to prevent vascular collapse

-intubation may be necessary

latex allergies

latex proteins can become aerosolized through powder on gloves and can be inhaled

allergic reaction to latex can also result in an allergic reaction to?

bananas, avocados, kiwi, tomatoes, apples, chestnuts, melons

types of latex allergies