Allergic disorders Flashcards
Autoimmune disease
Reactions occur when self-antigens are recognized by the body’s normal defense mechanisms as foreign
- B cells become hyperactive
- increased amount of IgE
- result = hypersensitivity or allergy response
What does hypersensitivity lead to?
Inflammation and destruction of healthy issue
What factors play a role in autoimmune disorders?
Genetric, hormonal and environmental
IgE-mediated allergic reactions: Atopic causes
- Hereditary predisposition and production of local reaction to IgE antibodies
- Allergic rhinitis
- Asthma
- Dermatitis/eczema
IgE-mediated allergic reactions: nonatopic causes
Lack of the genetic component and organ specific
Tetanus vaccine
Insect venom
Airborne allergens
Diagnostic testing for allergic disorders
CBC Eosinophil count IgE levels Skin test Radioallergosorbent testing Proactive testing
How can you obtain an eosinophil count?
nasal secretions/sputum
When would someones IgE levels be high?
with allergic diseases
Type 1 hypersensitivity
Anaphylactic
Type 1 (anaphylactic) s/s
Rapid onset
Edema in many tissues (larynx)
Hypotension, bronchospasm, cv collapse,
Local and systemic anaphylaxis
What is type II hypersensitivity?
Cytotoxic – system mistakenly identifies a normal constituent as foreign
Possible cell and tissue damage
Type 2 hypersensitivity (cytotoxic) – Myasthenia Gravis
mistakenly generates antibodies against normal nerve ending receptors
What is a type III hypersensitivity called?
Immune complex – formed when antigens bind to antibodies
– deposited in tissues or vascular endothelium
Result: increase in vascular permeability and tissue injury
What is type 4 hypersensitivity called?
Delayed-type – t-cell depended macrophage activation and inflammation cause tissue injury
example: TB test
What is anaphylaxis?
Severe allergic reaction - rapid onset - various systemic reactions
Type 1 hypersensitivity
When does an anaphylactic reaction occur?
Occurs when immune system produces IgE antibodies toward a substance that is normally nontoxic.
Antibodies are stored after initial exposure.
Re-exposure releases excess amounts of protein histamine.
what are s/s of histamine release?
Flushing, urticaria, angioedema, hypotension, bronchoconstriction
What are common foods that cause anaphylaxis?
peanuts tree nuts (walnuts, pecans, cashews, almonds) shelfish (shrimp, lobster, crab) fish milk soy wheat
What are common medications that can cause anaphylactic reaction?
Antibiotics (especially penicillin and sulfa antibiotics) allopurinol
radiocontrast agents
anesthetic agents (lidocaine, procaine)
vaccines
hormones (insulin, vasopressin, adrenocorticotropic hormone [ACTH]
aspirin
nonsteroidal anti-inflammatory drugs [NSAIDs]).
What are other pharmaceuticals/biologic agents that can cause anaphylactic reaction?
Animal serums (tetanus antitoxin, snake venom antitoxin, rabies antitoxin), antigens used in skin testing
What insect stings can cause anaphylaxis?
Bees, wasps, hornets, yellow jackets, ants (including fire ants)
what is a common medical item that can cause an anaphylactic reaction?
Latex - medical and non-medical products
The severity of an anaphylactic reaction depends on what?
The degree of allergy and the dose of allergen
Anaphylactic patterns: Uniphasic
Symptoms within 30 minutes of exposure
Resolve within 1-2 hours with or without treatment
Anaphylactic patterns: biphasic
Initial reaction – followed by subsequent symptoms up to 8 hours after first reaction
Need to be managed in ER
Anaphylactic patterns: protracted
Reaction that may last for 32 hours
Can include cardiogenic or septic shock and respiratory distress despite medical treatment
Anaphylaxis: mild s/s
Peripheral tingling Sensation of warmth Sensation of fullness in the mouth and throat Nasal Congestion Periorbital swelling Pruritus Sneezing Tearing of the eyes
Anaphylaxis: moderate s/s
Flushing Warming Anxiety Itching Includes all mild symptoms Bronchospasm & edema of airway and larynx with dyspnea, cough and wheezing Within 2 hours of exposure
Anaphylaxis: severe reaction
Rapid Progression of symptoms Bronchospasm Laryngeal edema Sever dyspnea Cyanosis Hypotension Abrupt onset Dysphagia Abdominal Cramping Vomiting/Diarrhea Seizures Cardiac Arrest
What is important to monitor when someone has an anaphylactic reaction?
Hemodynamic stability - HR, Rhythm, BP
Anaphylaxis reactions mngmnt
Strict avoidance of potential allergens Screening patients for allergies prior to medication Wear a medical alert bracelet Desensitizing Epinephrine
Epinephrine education considerations
No preparation
Carry it with you at all times
Education on how to administered
If used, must go to ER for monitoring for 12-14 hours
Anaphylaxis - medical management
Respiratory and cv - must be evaluated
High concentration of CO2 if cyanotic, dyspneic or wheezing
How to administer epi?
Upper extremity or thigh - SQ first
- IV if still needed
Adverse responses: epi
Mostly occur when given too much or given IV
High risk patients = elderly, HTN, arteriopathies, ischemic heart disease
When should you do if someone goes into cardiac arrest while treating them for anaphylactic reaction
Begin CRP then administer high concentration of o2
Anaphylaxis - antihistamines
onset use and types
Can take up to 80 minutes to only do 50% of the suppression
Used for urticaria and angioedema
H1: Diphenhydramine and Hydroxyzine
H2: Cetirizine and Loratadine and Fexofenadine
Anaphylaxis treatment: adrenergic agents do what?
Vasoconstriction of mucosal vessels
Limited use to avoid rebound congestion
What are sfx of adrenergic agents?
HTN, dysrhythmias, palpitations, CNS stimulant, irritability, tremors
What are examples of adrenergic agents for anaphylaxis treatment
Afrin - nasal
Alphagan P - eyes
Anaphylaxis - corticosteroid treatment
Used for urticaria & angioedema
Suppress major symptoms
Can take 2 weeks for full effect
Taper dosing
Anaphylaxis treatment: IV fluids (NS), volume expanders, vasopressors
maintains BP and hemodynamics
Anaphylaxis treatment: aminophyline
Used in conjunction with corticosteroids
Used on patients with Asthma or COPD
Improve airway patency and function
What do we need to monitor while taking diphenhydramine?
anticholinergic effects – dry mouth, constipation, difficult urinating, loss of accommodation – acetachloline is your parasympathetic
Anaphylaxis: nursing management
Initial action - access the patient for s/s of anaphylaxis
- assess airway, breathing pattern and other vitals
- increased edema and respiratory distress
Call 911 and initiation of emergent measures
Once recovered: explanation to avoid future exposure
In the event of an acute allergic reaction, the nurse recognizes that ET intubation may be difficult or impossible because it can result in increased laryngeal edema, bleeding, and further narrowing of the glottic opening. Fiberoptic ET intubation, needle cricothyrotomy (followed by transtracheal ventilation), or cricothyrotomy may be necessary
what is allergic rhinitis
Hay Fever, seasonal allergic rhinitis – Most common form of chronic respiratory allergic disease
Caused by an allergen-specific IgE-mediated immunologic response
Often in conjunction with other conditions – conjunctivitis, sinusitis, and asthma
Severe symptoms can interfere with sleep, leisure and school/work activities
Untreated allergic rhinitis can lead to what?
Untreated – asthma, chronic nasal obstruction, chronic otitis media with hearing loss, anosmia
Because allergic rhinitis is induced by airborne pollens or molds, it is activated by the following seasonal occurrences:
Early spring: Tree pollen (oak, elm, poplar), mold spores
Early summer: Rose pollen (rose fever), grass pollen (timothy, red-top)
Early fall: Weed pollen (ragweed), mold spores
Allergic rhinitis clinical manifestations
Sneezing, nasal congestion Clear, watery, nasal discharge Itchy eyes and nose, lacrimation postnasal drip headache pain over paranasal sinuses Epistaxis Nasal congestion or rhinorrhea Enlarge anterior cervical lymph nodes Sinus tenderness on palpations
Allergic rhinitis: diagnostics
Nasal smear Peripheral blood counts Serum IgE Epicutaneous and intradermal testing Radioallergosorbent test (RAST) Food elimination and challenge Nasal provocation test
Allergic Rhinitis: avoidance therapy
Remove allergens
If acquires URI – take dep breaths and cough frequently to ensure gas exchange
Seek medical attention if get URI
Allergic Rhinitis tx: antihistamines
used for mild allergic disorders
Seasonal basis – not continuous
Allergic Rhinitis tx: adrenergic agents
Help relieve severity of symptoms of narrowing blood vessels in the nasal passageways
Allergic Rhinitis tx: mast cell stabilizers
Reducing the release of histamine and other mediators of the allergic response
Benefits may take 1-2 weeks
Allergic Rhinitis tx: corticosteroids
Anti-inflammatory actins – effective in preventing or suppressing the major symptoms of allergic rhinitis
Allergic Rhinitis tx: immunotherapy
Allergy shots
Allergic Rhinitis tx: homeopathic modalities
? look up ?
Allergic Rhinitis: avoidance
- air cleaners/purifiers, humidifiers dehumiditers, keeping windows closed during high pollen counts and windy conditions
- Remove dust-catching furnishings. PETS – remove
What is something to incorporate to reduce allergic rhinitis?
Using air-conditioning as much as possible
How can allergic rhinitis affect QOL?
producing fatigue, loss of sleep, poor concentration, and interference with physical activities.
What is contact dermatitis
Acute or chronic skin inflammation that results from direct skin contact with chemicals or allergens
What type of hypersensitivity is contact dermatitis
type 4
What are the types of contact dermatitis
Allergic
Irritant
Phototoxic
Photoallergic
Allergic contact dermatitis: etiology
Results from contact of skin and allergenic substance. Has a sensitization period of 10–14 days.
Allergic contact dermatitis: clinical presentation
Vasodilation and perivascular infiltrates on the dermis
Intracellular edema
Usually seen on dorsal aspects of hand
Allergic contact dermatitis: diagnostic testing
Patch testing (contraindicated in acute, widespread dermatitis)
Allergic contact dermatitis: treatment
Avoidance of offending material
Burow solution (aluminum acetate in water) is a drying agent for weeping skin lesions or cool water compress
Systemic corticosteroids (prednisone) for 7–10 days
Topical corticosteroids for mild cases
Oral antihistamines to relieve pruritus
Irritant contact dermatitis: etiology
Results from contact with a substance that chemically or physically damages the skin on a nonimmunologic basis. Occurs after first exposure to irritant or repeated exposures to milder irritants over an extended time.
Irritant contact dermatitis: clinical presentation
Dryness lasting days to months
Vesiculation, fissures, cracks
Most common on hands and lower arms
Irritant contact dermatitis: diagnostic testing
Clinical picture
Appropriate negative patch tests
irritant contact dermatitis: treatment
Identification and removal of source of irritation
Application of hydrophilic cream or petrolatum to soothe and protect
Topical corticosteroids and compresses for weeping lesions
Antibiotics for infection, and oral antihistamines for pruritus
Phototoxic contact dermatitis: etiology
Resembles the irritant type but requires sun and a chemical in combination to damage the epidermis.
Phototoxic contact dermatitis: clinical presentation
Similar to irritant dermatitis
Phototoxic contact dermatitis: diagnostic testing
Photopatch test
Phototoxic contact dermatitis: treatment
Same as for allergic and irritant dermatitis
Photoallergic contact dermatitis: etiology
Resembles allergic dermatitis but requires light exposure in addition to allergen contact to produce immunologic reactivity.
Photoallergic contact dermatitis: clinical presentation
Similar to allergic dermatitis
Photoallergic contact dermatitis: diagnostic testing
photopatch test
Photoallergic contact dermatitis: treatment
Same as for allergic and irritant dermatitis
What is Atopic Dermatitis
Type I immediate hypersensitivity disorder characterized by inflammation and hyperreactivity of the skin, often causing pruritus
Significant elevation of serum IgE and peripheral eosinophilia
s/s - atopic dermatitis
pruritus and hyperirritability of the skin
- Excessive dryness
- Immediate redness appears and followed in 15-30 second by pallor – persisting for 1-3 minutes
Atopic dermatitis - management
Stop the itching and scratching
Cope with the disorder
What kind of hypersensitivity is dermatitis Medicamentosa
Type 1
Dermatitis Medicamentosa: causes and s/s
Drug reactions
s/s:
Appear suddenly
Vivid color
Intense characteristics – similar of infectious origin
Disappear rapidly after the medication is withdrawn
Rash can be generalized or systemic
Dermatitis Medicamentosa management
Find the cause
Stabilize patient
Frequent assessments
Carry a card identifying their allergy to this medication
Urticaria is what type of hypersensitivity
Type 1 hypersensitivity allergic reaction
Urticaria s/s
Pinkish, edematous elevation
Vary in size and shape
Itch
Local discomfort
Angioneurotic Edema s/s
Deeper layers of the skin – diffuse swelling
Involves lips, eyelids, cheeks, hands, feet, genitalia and tongue
Suddenly – 2 hours – lasting 24-36 hours
s/s food allergy
urticaria, dermatitis, wheezing, cough, laryngeal edema, angioedema
GI – swelling of lips, tongue, abdominal pain, nausea, cramps, vomiting/diarrhea
Food allergy - management
Family to help recognize symptoms
Children – food allergies disappear over time
Education – read labels, contamination
What type of hypersensitivity of serum sickness
Type 3
What is happening with serum sickness?
Hypersensitivity complexes get deposited in tissues or vascular endothelium – increase vascular permeability and tissue injury – vasculitis
Often from prevention of infectious diseases – tetanus, PNA, rabies, diphtheria, botulism
Begins 6-10 days after administration – inflammatory reaction at the site of injection of the medication – followed by regional and generalized lymphadenopathy and fever
Serum sickness - s/s
Skin rash, joints are tender and swollen
Vasculitis – any organ, common in the kidney
Cardiac involvement
Serum sickness: management
treat the clinical syndrome symptomatically
Latex allergy is an implication with what other conditions?
Implicated in rhinitis, conjunctivitis, contact dermatitis, urticaria, asthma, and anaphylaxis
What food sensitivities are related to latex allegies?
kiwi, bananas, pineapples, mangoes, passion fruit, avocados, and chestnuts
What happens if latex allergy is a type 1 response?
rapid onset – urticaria, wheezing, dyspnea, laryngeal edema, bronchospasm, angioedema, hypotension, and cardiac arrest
Latex allergies: risk factors
healthcare workers, atopic allergies, multiple surgeries, factory workers
Latex allergy: prevention
Avoid latex if at all possible
Ask about Allergy prior to any procedure
A latex allergy can cause what?
Irritant contact dermatitis
Allergic contact dermatitis
