Immuno-diagnosis, skin prick tests Therapeutic strategies for Arthropod allergies Preventive strategies for Arthropod allergies Vaccination Specific allergen immunotherapy. Peptide immunotherapy Gene therapy

1. MANAGEMENT
OF Arthropod
Allergies
• Immuno-diagnosis, skin prick tests
• Therapeutic strategies for Arthropod allergies
• Preventive strategies for Arthropod allergies
MD Arthropod
D. Ibrahim

2. Immuno-diagnosis: Skin Prick Test
• Skin prick testing is an essential test procedure to confirm sensitization in IgE-
mediated allergic disease in subjects with rhino-conjunctivitis, asthma, urticaria,
anaphylaxis, atopic eczema, and food and drug allergy.
• The recommended method of prick testing includes the appropriate use of specific
allergen extracts, positive and negative controls, interpretation of the tests after 15–
20 minutes of application, with a positive result defined as a wheal ≥3 mm diameter.
General principle in SPT
SPT interpretation utilizes the presence and degree of cutaneous reactivity as a surrogate
marker for sensitization within target organs, i.e., eyes, nose, lung, gut and skin.
When relevant allergens are introduced into the skin, specific IgE bound to the surface
receptors on mast cells are cross-linked, mast cells degranulate, and histamine and other
mediators are released. This produces a wheal and flare response which can be
quantitated. Many different allergens can be tested simultaneously because the resultant
reaction to a specific allergen is localized to the immediate area of the SPT.

3. Skin Prick Testing
techniques
• Skin prick tests are usually performed on the inner
forearm. Any number of allergens can be tested, as few
as 3 or 4 or up to about 25 allergens. The following is a
brief overview of how the test is performed.
• Clean arm with soap and water or alcohol.
• The forearm is coded with a skin marker pen
corresponding to the number of allergens being tested.
Marks should be at least 2 cm apart.
• A drop of allergen solution is placed beside each
mark.
• A small prick through the drop is made to the skin
using a sterile prick lancet. A new lancet must be used for
each allergen tested.
• Excess allergen solution is dabbed off with a tissue.
• Observe skin reactions – if a reaction occurs it should
do so within 20–30 minutes.
• In addition to the allergens tested, there should be a
positive and negative control. The positive control,
usually a histamine solution, should become itchy within
a few minutes and then become red and swollen with a
“weal” in the center. The negative control, usually
a saline solution should show no response.

4. Interpretation of SPT results
There are a couple of grading scales used but the size of the weal is most accurate. The size of
the weal does not indicate the severity of the symptoms but shows us the degree of sensitivity
to the allergen.
Common problems with skin prick testing:
There are many reasons that cause a false-positive or false-negative skin prick test result.
Causes of a false-positive result
oA positive reaction from one test site may affect the result of a neighboring test site (place test sites
at least 2 cm apart)
oIrritant reaction
Causes of a false-negative result
• Medications such as antihistamines that block the effect of histamine (advise patients to stop taking
medication at least 72 hours prior to skin testing)
• Decreased reactivity of the skin in infants and elderly patients
• Allergen extract too diluted (especially with foods)
• Cross reacting allergens.
Weal size (mm) Old “+” scale Interpretation
<4 0+ Negative
5 – 10 ++ Mildly sensitive
10 – 15 +++ Moderately sensitive
>15 ++++ Very sensitive

5. • The development of safe and effective
medications for allergic diseases may depend on
the discovery of treatments that are more specific
for the atopic disease process, in order to avoid
side effects.
• Many drugs are now in development for the
treatment of atopic diseases, including asthma,
allergic rhinitis and atopic dermatitis. These
treatments are based on improvements in existing
therapies or on a better understanding of the
cellular and molecular mechanisms involved in
atopic diseases.
• Most of the many new therapies in
development are aimed at inhibiting components
of the allergic inflammatory response, but in the
future, there are real possibilities for the
development of preventative and even curative
treatments.
Therapeutic
Strategies for
allergic diseases

6. Corticosteroids.
Corticosteroids are the most effective treatment currently available for atopic diseases and high
doses of oral corticosteroids would control almost every atopic patient. However, systemic side
effects limit its long-term use.
Bronchodilators.
used for symptom relief in asthma but have no effect on the underlying inflammatory process.
Inhaled b2-adrenergic agonists are safe and highly effective bronchodilators.
Mediator antagonists.
Many inflammatory mediators are involved in atopic diseases, and in asthma. This implies that
inhibitors of single mediators would be unlikely to be of major clinical benefit.
- Antihistamines: New antihistamines, such as cetirizine, ebastine and astemizole, have been claimed
to have anti-asthma effects. These effects include an inhibitory effect on eosinophil chemotaxis, and
inhibition of eosinophil recruitment into asthmatic airways after allergen challenge.
- Antileukotrienes: 5-LO inhibitors (zileuton), and cysteinyl-leukotriene receptor (Cys-LT1) antagonists
(montelukast) have been developed for the treatment of asthma, and possibly other atopic diseases.
- Tryptase inhibitors: Mast-cell tryptase has several effects on airways, including increasing
responsiveness of airway smooth muscle to constrictors, increasing plasma exudation, potentiating
eosinophil recruitment and stimulating fibroblast proliferation. Some of these effects are mediated
by activation of the proteinase-activated receptor, PAR2. More potent tryptase inhibitors and PAR2
antagonists are now in development.

7. Cytokine modulators
• Multiple cytokines have been implicated in the pathophysiology of atopic diseases. There
are several possible approaches to inhibiting specific cytokines. These include the use of
drugs that inhibit cytokine synthesis (glucocorticoids, cyclosporin A and tacrolimus), and
drugs that block the signal-transduction pathways activated by cytokines:
- Anti-IL-5: Blocking antibodies to IL-5 inhibit eosinophilic inflammation and airway
hyperresponsiveness (AHR) in animal models of asthma. Humanized monoclonal antibodies to IL-5
have now been developed and a single injection reduces blood eosinophils for several weeks and
prevents eosinophil recruitment into the airways after allergen challenge.
- Anti-IL-4: IL-4 is critical for the synthesis of immunoglobulin E (IgE) by B lymphocytes and is also
involved in eosinophil recruitment to the airways. IL-4-receptor blocking antibodies inhibit allergen
induced AHR, goblet-cell metaplasia and pulmonary eosinophilia.
- Anti-IL-13: There is increasing evidence that IL-13 mimics many of the features of asthma,
including AHR and mucus hypersecretion. It is also a potent inducer of eotaxin secretion (Eotaxin is a
potent and eosinophil-specific chemoattractant) from airway epithelial cells.
- Anti-TNF: Tumor-necrosis factor (TNF-a is expressed in asthmatic airways and may be important in
amplifying asthmatic inflammation, through the activation of NF-kB, AP-1 and other transcription
factors. blocking antibody to TNF-a (infliximab) has produced remarkable clinical responses.

8. Chemokine inhibitors:
Chemokines are chemoattractant cytokine molecules. Chemokines may be crucial in the
recruitment of eosinophils in atopic patients. These chemokines act on a common receptor, the
CCR3 receptor, that is expressed predominantly on eosinophils. An antibody to human CCR3
blocks the chemotactic response of human eosinophils to all chemokines.
Tyrosine kinase inhibitors:
Spleen tyrosine kinase (Syk) is a protein tyrosine kinase that has a important role in
signaling of the high-affinity IgE receptor (FceRI) in mast cells. Syk inhibitors might have
several useful beneficial effects in atopic diseases.
Co-stimulation inhibitors:
Co-stimulatory molecules may be crucial in augmenting the interaction between
antigen-presenting cells (APCs) and CD4+ T lymphocytes. B7 is a type of integral
membrane protein found on activated antigen-presenting cells (APC) that, when paired
with either a CD28 or CD152 (CTLA-4) surface protein on a T cell. So, Blocking
antibodies to B7-2 inhibit the development of specific IgE, pulmonary eosinophilia and
AHR.

9. Immunosuppressants:
T lymphocytes may be important in initiating and maintaining the inflammatory process in
atopy through the release of cytokines that result in eosinophilic inflammation, indicating that
T-cell inhibitors may be useful in controlling atopic inflammation.
- The non-specific immunomodulator ,cyclosporin A, reduces the dose of oral steroids
needed to control asthma in patients with severe asthma.
- Topical tacrolimus seems to be effective in atopic dermatitis and is well tolerated.
- Novel immunomodulators that inhibit purine or pyrimidine pathways, such as
mycophenolate mofetil, leflunomide and brequinar sodium, may be less toxic and
therefore of greater potential value in asthma therapy.
Cell adhesion blockers:
Infiltration of inflammatory cells into tissues is dependent on adhesion of blood-borne inflammatory
cells to endothelial cells before migration to the inflammatory site. This depends upon specific
glycoprotein adhesion molecules. Monoclonal antibodies which inhibit these intracellular adhesion
molecules (ICAMs) may prevent inflammatory cell infiltration. Thus, a monoclonal antibody to ICAM-
1 on endothelial cells prevents the eosinophil infiltration into airways and the increase in bronchial
reactivity after allergen exposure in sensitized primates. Although blocking adhesion molecules is an
attractive new approach to the treatment of inflammatory disease, there may be potential dangers
in inhibiting immune responses leading to increased infections and increased risks of neoplasia.

10. Specific anti-allergic drugs
Although corticosteroids are effective in controlling atopic diseases, there are continuing
concerns about systemic side effects when high doses are needed. This has prompted a
search for more selective anti-inflammatory agents that would selectively target the
atopic disease process.
Cromones: The cromones (sodium cromoglycate and nedocromil sodium) are the most
specific anti-allergic drugs so far discovered. Topical application is effective in asthma,
rhinitis and allergic conjunctivitis. It was believed that the primary mode of action of
cromones involved inhibiting mast-cell mediator release It may inhibit mast-cell
degranulation
Anti-IgE:
Because release of mediators from mast cells in asthma is IgE-dependent, an attractive
approach is to block the activation of IgE using blocking antibodies that do not result in
cell activation. A humanized murine monoclonal antibody directed to the FceRI-binding
domain of human IgE (rhuMAb-E25) reduces allergen-specific IgE after intravenous
administration. This could be a realistic therapy for patients with more severe forms of
asthma or atopic dermatitis, in whom high IgE levels may be found.

11. Preventive strategies
for allergic diseases
• Vaccination
• Specific allergen immunotherapy.
• Peptide immunotherapy
• Gene therapy

12. Vaccination
• A relative lack of infections may be a factor that influences the development of atopy in
genetically predisposed individuals. This leads to the concept that vaccination may induce
protective Th1 responses to prevent sensitization and thus prevent the development of atopic
diseases. In this context, the following vaccinations are beneficial:
 Bacillus Calmette–Guérin (BCG) vaccine has been associated with a reduction in
atopic diseases in Japan. BCG reduced the formation of specific IgE in response to
allergen and the eosinophilic response and Aryl Hydrocarbon Receptor (AhR)
responses to allergen, with an increase in production of IFN- y.
 Mycobacterium vaccae is a nonpathogenic, saprophytic bacterium found
naturally in soil. M. vaccae is generally harmless to humans. Initial interest in M.
vaccae arose from observations that it might have potential therapeutic benefits
for certain allergic and autoimmune conditions. Some studies suggested that it
could modulate the immune system, shifting the balance from a Th2-type
response (which can be associated with allergic reactions) to a Th1-type
response.

13. Specific allergen immunotherapy (SIT)
- Allergen immunotherapy, also known as desensitization or hypo-sensitization.
- Treatment of allergic diseases consists in allergen avoidance and the use of
pharmacotherapy. This includes antihistamines, corticosteroids, antileukotrienes and
beta-2 agonists1. Although effective at controlling symptoms and inflammation, these
treatments can have side effects if used for a long time.
- In patients, where it has been demonstrated and documented that symptoms appear on
exposure to specific allergens, allergen-specific immunotherapy (SIT) should be indicated.
SIT is a treatment approach designed to alter the immune response to allergens,
ultimately reducing or eliminating symptoms triggered by allergen exposure. Thus, the
principle behind allergen immunotherapy shares similarities with vaccination. Both aim
to modify the immune response, but they achieve this in slightly different ways:
- Unlike pharmacotherapy, allergen immunotherapy provides long-term clinical benefits.
These include long-term disease remission, prevention of new atopic sensitizations, and a
reduction in disease progression from rhinitis to asthma.
Overview

14. 1. Identification of the Allergen:
The first step is to identify the exact cause of the allergic reaction. This is typically
done using skin testing or specific IgE blood tests.
2. Vaccine Preparation:
Once the specific allergen is identified, a vaccine containing a tiny amount of the
allergen is prepared.
3. Administration:
SIT typically involves two phases:
a) Up-dosing or Build-up Phase: This phase usually lasts several weeks to
months. During this time, the patient receives increasing amounts of the
allergen vaccine at regular intervals. This is typically done once or twice a
week.
b) Maintenance Phase: After reaching the maximum dose, the frequency of
injections decreases, usually to once every 2-4 weeks. This phase can last
for several years or even lifelong in some cases.
Specific allergen immunotherapy involves the followings:

15. 5. Mechanism of Action:
• The objective of immunotherapy is to direct the immune response away
from humoral immunity and toward cellular immunity, thereby encouraging the
body to produce fewer IgE antibodies and more CD4+ T regulatory cells that
secrete IL-10 and TGF-β, which skews the response away from IgE production.
• Oral immunotherapy also creates an increase in allergen-specific IgG4 antibodies
and a decrease in allergen-specific IgE antibodies, as well as diminished mast
cells and basophils, two cell types that are large contributors to allergic reaction.
4. Routes of Administration:
a) Subcutaneous: Subcutaneous immunotherapy (SCIT), also known as allergy shots, is the
historical route of administration and consists of injections of allergen extract.
b) Sublingual: Sublingual immunotherapy involves putting drops or a tablet of allergen
extracts under the tongue, which are then absorbed through the buccal mucosa.
c) Oral: Oral immunotherapy (OIT) involves feeding an allergic individual increasing
amounts of a food allergen in order to raise the threshold which triggers a reaction.
d) Transdermal: The introduction of transdermal immunotherapy in the form of topical
application. Topical creams are easier for both adults and children to apply at home.

16. 6. Safety:
While SIT is considered safe when administered under medical supervision, there's
a risk of allergic reactions, including anaphylaxis, with the injections. This is why it's
essential to get the shots in a setting where allergic reactions can be promptly
treated. Patients are typically observed for at least 30 minutes after receiving an
injection.
7. Duration of Treatment:
The duration of SIT varies, but many patients undergo treatment for 3-5 years. The
decision to stop therapy is typically based on the patient's clinical response and
the physician's assessment.
8. Contraindications and Precautions:
Contraindications can include certain medical conditions, such as uncontrolled
asthma, and certain medications, such as beta-blockers.
9. Alternative Therapies:
For those who can't undergo SIT or choose not to, it's essential to have an
emergency plan in place. This might include carrying an epinephrine auto-injector
and wearing a medical alert bracelet.

17. Peptide Immunotherapy
• Peptide immunotherapy is an emerging treatment approach that offers a potentially safer
and more efficient method of desensitization than the traditional whole-allergen specific
immunotherapy (SIT). Instead of using whole allergen extracts, peptide immunotherapy uses
small fragments (peptides) of the allergenic proteins, which are designed to modulate the
immune system without causing an allergic reaction.
Mechanism of Action:
Peptide immunotherapy is designed to induce tolerance by modulating the T-cell response.
The treatment aims to shift the balance from a Th2 (allergic) immune response to a Th1
(non-allergic) or regulatory T-cell response.
Potential Advantages Over Traditional SIT:
a) Safety: Since the peptides can't cross-link IgE, there's a potentially reduced risk of allergic
reactions during treatment.
b) Efficacy: By targeting T cells directly, peptide immunotherapy may offer a more effective and
rapid induction of tolerance.
c) Simpler Treatment Regimen: With increased safety and efficacy, the treatment regimen might
be shorter and more straightforward than traditional SIT.

18. • Allergic diseases are associated with the skewing of
immune responses towards (TH2) phenotype, resulting in
eosinophilic inflammation. TH2 cytokines, such as
interleukin (IL)-4, IL-5 and IL-13, promote IgE production,
mast cell differentiation, and eosinophil growth, migration
and activation which then lead to the pathologic
abnormalities in allergic diseases. Moreover, the impaired
function of regulatory T cells has been noted in allergic
diseases.
• To date, treatments for allergic diseases, such as
antihistamines, corticosteroids, bronchodilators and some
allergen-specific immunotherapy, are effective but costly
and require long-term and recurrent drug administration.
Moreover, despite all existing therapies, there are still a
considerable number of patients with a poor quality of life
due to uncontrolled or partially controlled asthma, that
could benefit from additional treatment options
• Gene therapy has been shown to be an effective, and
convenient treatment by delivering the allergen or the
therapeutic protein in the form of plasmid DNA in vivo to
modulate allergic immune responses.

19. How does gene therapy work?
Gene therapy works by altering the genetic code to recover the functions of critical proteins
The instructions for making proteins are carried in a person’s genetic code, and variants (or
mutations) in this code can impact the production or function of proteins that may be
critical to how the body works. Repairing of disease-causing genetic changes may restore
the role of these important proteins and allow the body to function as expected.
Gene therapy can compensate for genetic alterations in a couple
different ways:
• Gene transfer therapy: Introduces new genetic material into cells. If an altered gene
causes a necessary protein to be faulty or missing, gene transfer therapy can introduce
a normal copy of the gene to recover the function of the protein. Alternatively, the
therapy can introduce a different gene that provides instructions for a protein that
helps the cell function normally, despite the genetic alteration.
• Genome editing: A newer technique that may potentially be used for gene therapy.
Instead of adding new genetic material, genome editing introduces gene-editing tools
that can change the existing DNA in the cell. Genome editing technologies allow
genetic material to be added, removed, or altered at precise locations in the genome.

20. Which of the following is the first-line treatment for severe allergic reactions, including those caused by
arthropod stings or bites?
a) Oral antihistamines
b) Corticosteroids
c) Epinephrine (adrenaline)
d) Bronchodilators
Venom immunotherapy is primarily used to:
a) Treat acute allergic reactions to insect stings.
b) Prevent future allergic reactions to insect stings.
c) Cure insect venom allergies permanently.
d) Relieve itching and redness after an insect sting.
Before undergoing allergen-specific immunotherapy, a patient should:
a) Undergo skin testing or specific IgE blood tests to confirm the allergy.
b) Take high doses of antihistamines for a week.
c) Be stung by the arthropod again to observe the reaction.
d) All of the above.
How long is venom immunotherapy typically recommended for patients with severe insect sting allergies?
a) 3-6 months
b) 6-12 months
c) 1-3 years
d) 3-5 years or longer
For patients with a history of severe allergic reactions to arthropod stings, it's recommended to:
a) Avoid carrying epinephrine auto-injectors to reduce anxiety.
b) Carry an epinephrine auto-injector at all times.
c) Rely solely on oral antihistamines during reactions.
d) Immediately apply ice on the sting site and ignore other symptoms.
Assessment MCQs

21. The hygiene hypothesis suggests that:
a) Increased cleanliness and decreased exposure to certain microbes can lead to a higher
prevalence of allergies.
b) Keeping a home too clean can increase arthropod infestations.
c) Regular exposure to insect venom can cure allergies.
d) Dirty environments are the leading cause of arthropod allergies.
In some individuals, symptoms of an allergic reaction to an insect sting can manifest
hours after the sting. This is known as:
a) An immediate hypersensitivity reaction
b) A prophylactic reaction
c) A delayed hypersensitivity reaction
d) A pseudo-allergic reaction
Which of the following arthropods is NOT typically associated with venom that can cause allergic
reactions in humans?
a) Honeybees
b) Fire ants
c) Ladybugs
d) Wasps
Which of the following is a major allergen found in honeybee venom?
a) Tropomyosin
b) Mellitin
c) Albumin
d) Histamine

22. Which treatment method involves giving gradually increasing doses of the allergen to reduce
sensitivity?
a) Steroid therapy
b) Epinephrine prophylaxis
c) Allergen-specific immunotherapy
d) Anti-IgE therapy
Systemic allergic reactions to insect stings can manifest as:
a) Urticaria and swelling distant from the sting site
b) Mild pain at the sting site
c) An itch without any visible skin changes
d) Localized dry skin
A person who has experienced a systemic allergic reaction to an insect sting:
a) Is less likely to react to subsequent stings.
b) Will always react to subsequent stings.
c) Has a significant risk of experiencing another systemic reaction to subsequent stings.
d) Will only react if stung by a different species of insect.
A bite from which of the following arthropods can potentially trigger an allergy to red meat in some
individuals?
a) Mosquito
b) Lone Star tick
c) Bedbug
d) Sandfly

23. Which of the following is NOT a recommended strategy to avoid bee stings?
a) Swatting at flying bees
b) Keeping food covered when eating outside
c) Avoiding floral-patterned clothing
d) Staying calm and still if a bee approaches
In an allergic reaction to insect venom, which cell releases histamine and other mediators
when activated by allergens?
a) Eosinophils
b) Neutrophils
c) Basophils
d) Monocytes
For individuals with severe arthropod allergies, what is a long-term approach to reduce the
risk of anaphylaxis after a sting?
a) Taking daily antihistamines indefinitely
b) Allergen-specific immunotherapy
c) Regularly applying insect repellent creams
d) Weekly corticosteroid injections
An individual who is allergic to the venom of one species of wasp:
a) Will never be allergic to bee venom.
b) Might also be allergic to the venom of other species of wasps or bees.
c) Can safely handle other arthropods without risk.
d) Is more likely to be allergic to ant bites.

24. How should epinephrine auto-injectors be stored for individuals at risk of anaphylaxis from insect stings?
a) In the refrigerator
b) In direct sunlight
c) At room temperature, away from extreme heat or cold
d) In a vehicle's glove compartment for easy access
After using an epinephrine auto-injector due to a suspected severe allergic reaction to an insect sting, what
should an individual do next?
a) Resume regular activities
b) Lay down and rest at home
c) Seek immediate medical attention or call emergency services
d) Take a cold shower to soothe the sting site
John, a 35-year-old man, is stung by a bee while gardening. He experiences difficulty breathing, rapid heartbeat,
and widespread hives.
What is the most immediate first-line treatment John should receive?
a) Oral antihistamines
b) Corticosteroids
c) Epinephrine (adrenaline) injection
d) Painkiller
Case Scenario 2: Maria, a 28-year-old woman, visits her allergist after experiencing localized swelling and itching
after a wasp sting. She is concerned about potential future reactions. What might her allergist recommend to
determine her risk of a severe allergic reaction to future stings?
a) Complete blood count
b) X-ray of the sting site
c) Skin testing or specific IgE blood tests
d) A full body scan

25. Case Scenario 3: David, a 40-year-old man, is known to have a severe allergy to fire ant stings. While on a
camping trip, he forgets his epinephrine auto-injector at home. In case David gets stung by a fire ant and starts to
show signs of an allergic reaction, what should he do?
a) Wait for symptoms to subside on their own
b) Apply a tourniquet above the sting site
c) Seek immediate medical attention or call emergency services
d) Take a nap to calm down
Case Scenario 4: Lisa, a 50-year-old woman, has undergone allergen-specific immunotherapy for her known bee
venom allergy. She is on her maintenance phase and receives injections every month. How long might Lisa
typically need to continue her maintenance venom immunotherapy?
a) 3-6 months
b) 6-12 months
c) 1-3 years
d) 3-5 years or longer
Case Scenario 5: Alex, a 22-year-old college student, was recently diagnosed with a mosquito allergy. After
getting bitten, he develops large areas of redness and swelling, much larger than typical mosquito bites. What is
a suitable treatment option to reduce the itching and swelling for mosquito bites?
a) Regularly consume alcohol to improve blood flow
b) Oral antihistamines and topical corticosteroid creams
c) Immediate epinephrine injection
d) Intravenous antibiotics
Case Scenario 6: Sarah, a 29-year-old woman, visits a tropical country for vacation. After her return, she notices a
strange rash and recalls being bitten by some unfamiliar insects during her trip. What should be Sarah's
immediate course of action after noticing the rash?
a) Ignore it, thinking it's a temporary travel-related rash
b) Apply hot water on the rash
c) Consult a doctor or dermatologist to rule out any tropical arthropod-related disease
d) Start taking antibiotics she has at home

26. Case Scenario 7: Kevin, a 45-year-old hiker, gets stung by an insect. He's not sure which one, but soon after he
experiences abdominal pain, dizziness, and a drop in blood pressure. Kevin's symptoms suggest that he might be
experiencing:
a) A mild allergic reaction
b) Anaphylaxis
c) Food poisoning
d) A regular insect bite response
Case Scenario 8: Emily, a 33-year-old woman, knows she's allergic to bee stings. She's attending an outdoor
summer party. Which precaution should Emily especially consider to minimize her risk of getting stung?
a) Avoid drinking any fluids during the party
b) Keep her skin fully covered with heavy clothing
c) Avoid wearing floral or brightly colored clothing
d) Stay indoors throughout the entire event
Case Scenario 9: Rahul, a 50-year-old man with a history of severe reactions to hornet stings, is mowing his lawn
when he accidentally disturbs a hidden hornet's nest. He gets stung multiple times. What is the best course of
action for Rahul after being stung?
a) Remove the stingers by squeezing them out
b) Administer his epinephrine auto-injector and then seek emergency medical attention
c) Wait to see if he develops any allergic symptoms before taking any action
d) Apply ice on all the sting sites and continue mowing
Case Scenario 10: Clara, a 27-year-old woman, undergoes allergy testing and finds out she's allergic to a specific
type of ant. She's provided with an epinephrine auto-injector as a precaution. Clara's friend advises her to test
the auto-injector on herself to know how it feels. What should Clara do?
a) Test the auto-injector to familiarize herself
b) Only use the auto-injector in the event of a severe allergic reaction
c) Carry the auto-injector but rely mainly on oral antihistamines
d) Return the auto-injector since she's never had a severe reaction before

27. D. Ibrahim
Abouelasaad