Immunocompetence is when the bodys immune system is

IMMUNOCOMPETENCE IS WHEN THE BODYS IMMUNE SYSTEM IS ABLE TO IDENTIFY
AND INACTIVATE OR DESTROY FOREIGN SUBSTANCES.
When the immune response doesn’t work , patients get severe infections,
immunodeficiency diseases and malignancies. When the immune response
overreacts, hypersensitivity disorders which as allergies and autoimmune diseases
may develop.
HYPERSENSITIVITY DISORDERS: The immune system can overreact OR react
against its own tissue, resulting in tissue damage. These reactions are called

hypersensitivity reactions. Autoimmune diseases are a type of hypersensitivity
response and occurs when the body reacts to “self” antigens. We will talk about
this a little later on.
There are 4 types of hypersensitivity reactions. Types I, II and III are immediate and
are examples of humoral immunity. Type IV is a delayed hypersensitivity reaction
and is related to cell-mediated immunity.
Type I: IgE-Mediated
Anaphylaxis occur when a person is highly sensitized to specific allergens. When
the antigen is present, there are clinical symptoms of an allergic response. The
patients will have smooth muscle contraction, increased vascular permeability,
vasodilation, hypotension, increased secretion of mucous and itching. Many allergic
responses are hereditary. In an allergic response, the mediators like histamine,
leukotrienes, prostaglandins and serotonin are short acting, therefore, the effects
are reversible. The patient with an anaphylactic reaction will have different
presentations, depending on whether the mediators remain localized, or become
systemic AND whether or not the mediators affect particular organs. When the
mediators remain local, it is called the “wheal and flare reaction”, where a pale
wheal containing edematous fluid is surrounded by a red flare from the hyperemia.
This reaction occurs in minutes to hours and usually is not dangerous.
Classic…..mosquito bite. This wheal and flare reaction serves as a diagnostic tool
when attempting to determine which allergens a patient responds to during a skin
test. Common allergic reactions include anaphylaxis and atopic reactions.
Anaphylaxis can occur with mediators are released systemically (following an
injection or after an insect sting). This reaction is within minutes and can be life
threatening because of bronchial constriction, which can lead to airway obstruction
and vascular collapse. Initial symptoms include itching at the site of exposure.
Shock can come on quickly and is manifested by a rapid, weak pulse; hypotension;
dilated pupils’ dyspnea and possibly cyanosis. This is compounded by bronchial
edema and angioedema. Can result in death if not treated quickly. Drugs are the
leading antigen leading to anaphylaxis, however it can also be caused by food,
treatment measures to include blood products and contrast media, insect venoms
and animal sera, which is used to make antitoxins to some things like diphtheria,
rabies, snake venom and tetanus.