Question

Kevin, a 54-year-old personal trainer hears a bee uzzing around his gym. Kevin anxiously opens the windows and doors in hopes the bee will fly out. Kevin mentions he has a severe allergy to bee venom and carries an EpiPen in the event he is stung. 1. Which hypersensitivity (I, II, III or IV) does Kevin suffer from? (1p) 2. Explain what happens to the immune system upon the first exposure (first bee sting) to bee venom. For full credit, include the following terms: allergen (bee venom), basophils/mast cells, plasma B cells, and IgE. (lp) 3. Next, explain what happens to the immune system upon a second exposure (second bee sting) to bee venom. For full credit, include the following terms: allergen (bee venom, basophils/mast cells, memory B cells, IgE and histamine. (Ip) 4. Anaphylaxis can result from severe allergic reactions. What are the signs and symptoms of anaphylaxis? How do you know if a patient has anaphylactic shock? (1p) 5. Research what epinephrine does to the body and state why it is useful in treating anaphylactic shock. (lp)

Answer 1

ANSWER:- 1. TYPE I hypersentivity.

2. When a bee stings you, a chemical is released is know as Allergen. In anaphylactic reaction body's immune system thinks that the allergen is a foreign Invader. In response to this illusion the immune system releases the antibodies.These antibodies recognize the allergen & bind to it.

These antibodies also causes the release of some other chemicals like- histamine, serotonin & leukotriene. These chemicals can cause the symptoms like- Itchy feeling ,difficulty in swallowing ,hives, nausea ,increased heart rate,a sudden feeling of weakness,collapse & unconsciousness ,difficulty in breathing & ultimately death.

4. Anaphylaxis most commonly affects the cutaneous, respiratory, cardiovascular, and gastrointestinal systems. The skin or mucous membranes are involved in 80-90% of cases. A majority of adult patients have some combination of urticaria, erythema, pruritus, or angioedema. However, for poorly understood reasons, children may present more commonly with respiratory symptoms followed by cutaneous symptoms. ^[3] It is also important to note that some of the most severe cases of anaphylaxis present in the absence of skin findings.

Initially, patients often experience pruritus and flushing. Other symptoms can evolve rapidly, such as the following:

• Dermatologic/ocular: Flushing, urticaria, angioedema, cutaneous and/or conjunctival injection or pruritus, warmth, and swelling

• Respiratory: Nasal congestion, coryza, rhinorrhea, sneezing, throat tightness, wheezing, shortness of breath, cough, hoarseness, dyspnea

• Cardiovascular: Dizziness, weakness, syncope, chest pain, palpitations

• Gastrointestinal: Dysphagia, nausea, vomiting, diarrhea, bloating, cramps

• Neurologic: Headache, dizziness, blurred vision, and seizure (very rare and often associated with hypotension)

• Other: Metallic taste, feeling of impending doom

See Clinical Presentation for more detail.

Diagnosis

Anaphylaxis is primarily a clinical diagnosis. The first priority in the physical examination should be to assess the patient’s airway, breathing, circulation, and adequacy of mentation (eg, alertness, orientation, coherence of thought).

Examination may reveal the following findings:

• General appearance and vital signs: Vary according to the severity of the anaphylactic episode and the organ system(s) affected; patients are commonly restless and anxious

• Respiratory findings: Severe angioedema of the tongue and lips; tachypnea; stridor or severe air hunger; loss of voice, hoarseness, and/or dysphonia; wheezing

• Cardiovascular: Tachycardia, hypotension; cardiovascular collapse and shock can occur immediately, without any other findings

• Neurologic: Altered mentation; depressed level of consciousness or may be agitated and/or combative

• Dermatologic: Classic skin manifestation is urticaria (ie, hives) anywhere on the body; angioedema (soft-tissue swelling); generalized (whole-body) erythema (or flushing) without urticaria or angioedema

• Gastrointestinal: Vomiting, diarrhea, and abdominal distention

5. Epinephrine is the drug of choice for treating anaphylaxis. It has alpha-agonist effects that include increased peripheral vascular resistance and reversed peripheral vasodilatation, systemic hypotension, and vascular permeability. Its beta-agonist effects include bronchodilatation, chronotropic cardiac activity, and positive inotropic effects.