What is the third step in the allergic cascade?
Click to see answer
Late-phase response to an allergen.
Click to see question
What is the third step in the allergic cascade?
Late-phase response to an allergen.
What are the two main classifications of adverse reactions to food?
Toxic and Non-toxic (host specific).
Where is epinephrine produced in the body?
By the adrenal gland.
What causes allergies?
Hypersensitivity of the immune system to environmental substances.
What do many insurers consider allergies or asthma related to allergies?
A pre-existing condition.
What is the primary function of the immune system?
To protect the body from potentially harmful foreign molecules.
What can infant-onset food allergies trigger later in life?
Other allergic diseases.
What is the typical evolution of allergic disease associated with asthma?
It often includes asthma and allergic rhinitis.
How much does a single consultation with an allergist cost in Hong Kong?
Around HKD 1,600, excluding medications.
Which test measures specific antibodies in the blood to diagnose food allergies?
Blood Test.
What is the primary strategy for managing food allergies?
Avoid the allergen-containing food(s).
What is epinephrine also known as?
Adrenaline.
What percentage of immune activity occurs in the intestinal tract?
Over 60%.
What percentage of children in Hong Kong are affected by food allergies?
5 - 8%.
Why is the intestinal tract significant for the immune system?
Because the majority of potentially harmful molecules enter the body through it.
When is epinephrine produced?
During the 'flight-or-fight' response.
What percentage of children aged 2 - 7 in Hong Kong have shown adverse effects from food?
8.1%.
What is the primary use of steroids in the context of the immune system?
To calm down the immune system cells.
What is the purpose of the Skin Prick Test?
To identify allergic reactions to specific allergens.
How long can the late-phase response last?
It can last for about 24 hours before subsiding.
Should steroids be used to treat anaphylaxis?
No, they should not be used for anaphylaxis.
What type of allergies can be detected through double-blind placebo-controlled food challenges?
Non-IgE mediated allergies.
What are some examples of foods that can cause allergies in the meat category?
Beef, lamb, and pork.
What is the role of macrophage cells in the immune system?
They act as 'scavenger' cells, removing and destroying damaging molecules.
What is a typical cutaneous symptom of IgE-mediated reactions?
Urticaria.
What skin condition is associated with Celiac Disease?
Dermatitis herpetiformis.
What is the first step in the allergic cascade?
Sensitization.
How can steroids be administered?
Orally or through injection.
What are mast cells?
Tissue cells of the immune system that cause allergic symptoms.
What type of spicy food can cause allergic reactions?
Hot peppers.
What is atopic dermatitis?
A cutaneous symptom associated with IgE-mediated reactions.
What organization conducted the food allergy perception survey in 2007?
IFIC Foundation.
What is a common screening tool for diagnosing food allergies?
Skin Prick Test.
Is the prevalence of food allergies higher in boys or girls in Hong Kong?
Slightly more among boys.
Where is the immune system most active in the body?
In areas with direct contact with the outside world, such as the skin, lungs, nose, and gastrointestinal tract.
What are the three levels of allergy prevention according to the World Allergy Organization?
Primary, Secondary, and Tertiary Prevention.
What is the typical evolution of allergic disease without asthma?
It may occur without asthma and allergic rhinitis.
What is the function of antihistamines?
They block the action of histamine.
What happens during the sensitization phase of an allergic reaction?
The body produces IgE antibodies specific to an allergen without experiencing a reaction.
What is the prevalence of food allergies in Germany?
2 - 3%.
Which immune cells are primarily involved in the late-phase response?
Eosinophils.
How many people are affected by asthma globally?
300 million.
What percentage of all food allergies do the 'Big 8' allergens account for?
More than 90%.
What is the definition of food allergy?
An abnormal immune response to specific food proteins.
What emergency therapy is recommended for food allergies?
Epinephrine (adrenaline) shot.
What are common gastrointestinal symptoms of Celiac Disease?
Mouth sores, abdominal bloating and pain, diarrhea, and steatorrhea.
What trend was observed in the incidence of food-induced anaphylaxis between 2009 and 2019?
There was more than a twofold increase in incidence.
What is the issue with allergy specialists in Hong Kong?
The ratio of allergy specialists per population is quite low.
What do B-cells produce?
Antibodies.
What percentage of children under 3 years of age have food allergies?
6%.
What percentage of the entire US population do people think have food allergies according to the survey?
25%.
How many participants were involved in the food allergy perception survey in the US?
1000 participants.
Are allergy tests and treatments expensive in Hong Kong?
Yes, they are very expensive.
How many emergency room visits are estimated per year due to food-induced anaphylaxis in the US?
50,000.
What is a potential consequence of having allergies classified as a pre-existing condition by insurers?
You may not be eligible for coverage.
What occurs following exposure to an allergen?
A series of reactions in the immune system.
What is the estimated number of deaths per year due to food-induced anaphylaxis in the US?
150 - 200.
What is histamine?
One of the major mediators that causes blood vessels to dilate and become leaky to plasma proteins.
What is anaphylactic shock?
A generalized shock reaction that can lead to multiple organ failure.
Is food-induced anaphylaxis considered rare?
No, it is not rare.
What is the first step in the allergic cascade?
Sensitization to an allergen.
What percentage of school-aged children are affected by one or more forms of allergy?
40 - 50%.
What effect does histamine have on sensory nerve terminals?
It causes itchiness.
How does the prevalence of food allergies vary among different age groups in Hong Kong?
It is similar among different age bands (infant, toddler, preschooler, primary school children, early secondary school children).
What are the severe symptoms of anaphylactic shock?
Severe loss of blood pressure and cardiac arrhythmia.
What is a food challenge in the context of food allergy diagnosis?
A test where the patient consumes the suspected allergen under medical supervision.
What is the second step in the allergic cascade?
Early-phase response upon re-exposure to an allergen.
How many children had food allergies in 2012?
4.1 million.
What can trigger allergic reactions in sensitive individuals?
Trace amounts (ppm concentrations) of the offending food.
What can happen if anaphylactic shock is not treated immediately?
It can be fatal.
What percentage of food allergies in Hong Kong are single item allergies?
85%.
What is the likelihood of infants outgrowing their food allergies?
Most infants outgrow their allergy within months, especially if it occurs before 3 years of age.
What is the prevalence of food allergies in Australia?
1 - 2% of the population.
What is the late-phase response in allergic reactions?
A secondary immune response that begins at the same time as the early-phase response but takes longer to manifest.
How many children had skin allergies in 2012?
8.8 million.
What is a Food Allergy Action Plan?
A plan that includes informing family, friends, and caretakers about the allergy.
What is the risk for infants with eczema regarding asthma and allergic rhinitis?
They have a higher risk of developing asthma and allergic rhinitis.
What are the primary causative agents of food allergies?
Naturally-occurring proteins.
What type of allergy is characterized by a chronic inflammatory response?
IgE mediated allergy.
What role do T-cells play in the immune system?
They conduct surveillance for potentially dangerous molecules and kill dangerous cells such as disease-causing bacteria.
What is the prevalence of food allergies in The Netherlands?
5%.
What type of proteins are usually responsible for food allergies?
Major proteins of the food.
How quickly do food allergy symptoms typically occur after exposure?
Within minutes to several hours.
What should be considered when using oils in relation to allergens?
Proceed with caution; highly refined oils largely remove protein, but cold-pressed oils may contain allergenic proteins.
When was the Hong Kong Institute of Allergy founded?
In 1996.
What type of allergic response is characterized by T-cells and macrophages?
Non IgE mediated Cell-Mediated Allergic Response.
What are examples of allergens that can be inhaled?
Pollen, mold, dust mites.
How many times were patients admitted for anaphylaxis during the 11-year span?
2,961 times.
What are mast cells compared to in the context of sensitization?
Little bombs that are armed and ready for explosion.
What condition is associated with gluten intolerance?
Celiac disease.
What is the risk percentage of allergic reactions to peanuts?
5%.
How long does it usually take for symptoms of an allergic reaction to appear?
It can take several days.
What type of allergy is characterized by an IgE mediated response?
IgE mediated allergy.
What is an example of a non IgE mediated allergic response?
Celiac Disease.
Does a positive skin prick test guarantee a reaction to that food when eaten?
No, it does not guarantee a reaction.
What are some management strategies for food allergies?
Avoidance of allergens, carrying emergency medication, and education.
Will reactions always become increasingly severe each time you have one?
No, reactions do not always become increasingly severe.
Can non-IgE mediated allergies be detected by the RAST test?
No, they cannot be detected.
What is the risk of allergy in infants fed with intact cow's milk protein after the first week of life?
20-30%.
What is the highest reported risk of allergy in infants?
50-60%.
What is an example of a food related to cow's milk that may cause allergic reactions?
Beef (hamburger).
Which food allergies are most commonly outgrown within the first ten years of life?
Allergies to milk, eggs, soy, and wheat.
What percentage of the Canadian population has food allergies?
1 - 2%.
What percentage of individuals outgrow peanut allergies?
Only 20%.
How many people are affected by allergic rhinitis globally?
400 million.
What does Secondary Prevention involve?
Staying away from known allergens.
What type of adverse reaction is a food allergy classified as?
Immune mediated.
What effect does epinephrine have on allergic reactions?
It reverses the allergic reaction by improving blood circulation.
What are the substances released by mast cells during an allergic response?
Histamine and other inflammatory mediators.
What type of allergy is associated with a late phase response?
IgE mediated allergy.
What is the prevalence of food allergies among adults in the US?
3.7%.
What symptoms can be more severe during the late-phase response compared to the initial response?
Congestion and certain other symptoms.
Where do IgE antibodies bind after being produced?
To special receptors on mast cells.
What is the role of Immunoglobulin E (IgE) in food allergies?
It is involved in IgE-mediated reactions.
What is the prevalence of celiac disease in the U.S.?
3.5 million people.
Which cytokine is involved in the late phase response?
Tumor Necrosis Factor - α (TNF - α).
Are food allergies common globally?
Yes.
What occurs during the early-phase of an allergic reaction?
Immediate release of mediators from mast cells and basophils.
What does ingestion of an allergen refer to?
Swallowing a type of food or medication.
What is the main goal of the Hong Kong Institute of Allergy?
To share the most up-to-date knowledge on the management of allergic diseases.
What are common symptoms of food allergies?
Symptoms can include hives, swelling, abdominal pain, and anaphylaxis.
What type of allergies cannot be detected by the Skin Prick Test?
Non-IgE mediated allergies.
What is involved in the diagnosis of a food allergy?
Clinical history, skin tests, and specific IgE tests.
What is the risk percentage of allergic reactions to tree nuts?
37%.
What is the prevalence of food allergies worldwide?
Food allergies affect millions of people globally, with varying rates by region.
What is the main focus of the Hong Kong Allergy Association?
To raise public awareness of allergy through education and provide support to those with allergies.
What are the effects of smooth muscle contraction in an allergic response?
It can lead to symptoms like dyspnea.
What role does histamine play in allergic reactions?
Histamine causes symptoms such as itchiness and rhinorrhea.
How does gluten affect the small intestine in celiac disease?
It damages the villi, making it difficult to absorb nutrients.
What are the effects of IgE mediated allergies?
Acute effect, late-phase effect, and chronic effect.
What is the risk percentage of allergic reactions to grains?
20%.
What is an example of Primary Prevention for allergies?
Breastfeeding and avoiding second-hand smoke and air pollutants.
What happens during the early-phase response upon re-exposure to an allergen?
IgE of mast cells binds to the allergen, leading to cross-linking.
What is the primary treatment for anaphylactic shock?
Epinephrine.
What is important for early detection of allergic reactions?
Early symptom recognition.
Which food allergies are often lifelong?
Peanut, tree nut, fish, and shellfish allergies.
What type of antibodies are involved in allergic reactions?
Immunoglobulin E (IgE) antibodies.
What is the focus of Tertiary Prevention?
Treatment and medication to reduce the risk of allergy.
What percentage of children with food allergies in Hong Kong have seen a doctor for a diagnosis?
4.6%.
What do IgE antibodies bind to in the allergic response?
An allergen and then to a receptor on mast cells.
What is an EpiPen?
A self-injectable device for administering epinephrine.
What can help identify individuals with food allergies in emergencies?
Medical identification necklaces or bracelets.
How can a person be initially exposed to an allergen?
Through inhalation, ingestion, touch, or injection.
What percentage of the population in Italy has food allergies?
6 - 8%.
How quickly do symptoms of an allergic response occur after re-exposure?
Within an hour after initial exposure.
What does it mean to be atopic?
Having an inherited sensitivity toward allergic disease.
What are examples of foods that can cause allergies?
Peanut, Mushroom, and Lactose.
Who organized the Hong Kong Institute of Allergy?
A group of Allergists, Respirologists, Paediatricians, and Dermatologists.
Are food allergies dangerous?
No, food allergies can be dangerous.
What are some chronic structural changes caused by allergic inflammation?
Muscle hypertrophy and organ dysfunction.
Which group of patients was significantly less likely to have prescriptions for adrenaline auto-injectors?
Adult patients.
What percentage of people with celiac disease are undiagnosed or misdiagnosed?
80%.
What cells contain mediators in IgE mediated allergies?
Mast cells.
What gastrointestinal symptoms can occur in IgE-mediated reactions?
Swelling of the lips, nausea, vomiting, abdominal pain, and diarrhea.
Where can skin testing be performed?
On the arm or back.
What is the risk percentage of allergic reactions to fish?
50%.
What are examples of other fish that may cause allergic reactions?
Swordfish, sole.
What are some examples of mediators released during mast cell activation?
Histamine and TNF-α.
What are some conditions that celiac disease can lead to?
Infertility, neurological disorders, some cancers, and other autoimmune diseases.
What happens if the patient's serum contains IgE antibodies?
Those antibodies will bind to the allergen.
What are examples of other grains that may cause allergic reactions?
Barley, rye.
How long after the initial allergic reaction can the late-phase response occur?
Anywhere from about three to 10 hours later.
What type of food challenge is conducted in a hospital environment?
Double-blind placebo-controlled food challenges.
Do antihistamines completely improve dangerous symptoms in anaphylaxis?
No, they do not completely improve the dangerous symptoms that affect breathing.
What is a food allergy?
An abnormal immune response to food.
What percentage of the United States population has food allergies?
4%.
What happens when an antibody binds to an antigen?
It identifies the molecule as potentially damaging and signals for its removal.
What do B cells produce in response to allergen sensitization?
IgE antibodies targeted to the specific allergen.
Can the 'Big 8' allergens be consumed raw or cooked?
Yes, they can be raw or cooked.
What are the two main types of immune responses in food allergies?
IgE mediated allergy and Non IgE mediated allergy.
What is a limitation of using steroids for treating allergic reactions?
They only relieve symptoms in the contact area and take a long time to work.
What do mast cells release that causes allergic symptoms?
Inflammatory chemicals such as histamine.
Which vegetable is mentioned as a potential allergen?
Garlic.
Where do many patients in Hong Kong go for allergy-related treatments?
To their general practitioners.
Which publication discusses the reaction pattern in food challenges?
Bindslev-Jensen C, BMJ 1998;316:1299.
What serves as a positive control in the Skin Prick Test?
Proven allergens like histamine.
How is the pathogenesis of non IgE mediated allergic responses defined?
It is not as clearly defined as for IgE mediated allergic responses.
What risk is associated with asymptomatic Celiac Disease?
Increased risk for malnutrition-related symptoms and complications.
What indicates an allergic reaction during the Skin Prick Test?
A hive forming at the injection site.
What is an example of an allergen that can be encountered through touch?
Poison ivy, latex, or certain metals like nickel.
When was the Hong Kong Allergy Association founded?
In 2008.
What are the two scenarios mentioned for the injection of an antigen?
Injection into the epidermis and response to an inhaled antigen.
What is a key feature of the acute response in IgE mediated allergies?
It occurs within minutes to 2 hours.
What are the two stages of IgE mediated allergy?
Sensitization and Mast cell activation.
What is anaphylactic shock?
A systemic symptom of IgE-mediated reactions that can be life-threatening.
What type of disorder is Celiac Disease?
A chronic inflammatory disorder of the small intestine.
What are some common symptoms of an IgE mediated allergy?
Symptoms include rhinorrhea, itchiness, dyspnea, itchy rash, throat swelling, and low blood pressure.
What are examples of other shellfish that may cause allergic reactions?
Crab, lobster.
What is the risk percentage of allergic reactions to cow's milk?
10%.
What are the 'Big 8' food allergens?
Milk, Eggs, Peanuts, Tree nuts, Soy, Wheat, Fish, Crustacean shellfish.
What are antibodies?
Long, branched molecules that recognize and bind to specific antigens.
What role do T cells play in sensitization to allergens?
T cells stimulate B cells to produce IgE antibodies.
Who is present during a double-blind placebo-controlled food challenge?
A doctor.
Which fruits are known to cause allergic reactions?
Mango and strawberries.
What does the WHO estimate about asthma prevalence by 2025?
400 million people will suffer from asthma.
What is the first step in the allergic cascade?
Sensitization to an allergen.
What is injected during an intradermal skin test?
A small amount of allergen just beneath the skin surface.
What can repeated allergen exposure lead to?
A chronic inflammatory response.
When does the late phase response occur after the original reaction?
2 to 24 hours.
What is used as a negative control in the Skin Prick Test?
Saline.
Can an antibody bind to multiple antigens?
No, an antibody will only bind to one specific antigen.
What is the function of macrophages in the immune system?
They act as scavenger cells to clean up residue and remove potentially dangerous substances.
Is processing and preparation information always available for allergenic foods?
No, it is not always available.
What do macrophages do after an antibody binds to a dangerous molecule?
They consume the molecule, taking it out of circulation and destroying it.
What can happen during a severe food allergy reaction?
Symptoms may include trouble breathing and low blood pressure.
What percentage of anaphylaxis survivors were prescribed adrenaline auto-injectors (AAI)?
Fewer than 15%.
What are the primary cells involved in non IgE mediated allergic responses?
T-cells, macrophages, and other cells.
How can allergens be introduced through injection?
By receiving a medication or being stung by an insect.
What areas of the body are affected by non IgE mediated allergic responses?
The gastrointestinal tract and skin.
What is the only treatment for celiac disease?
A strict gluten-free diet.
What type of disease is celiac disease?
A serious, genetic, autoimmune disease.
What triggers celiac disease?
Consuming gluten found in wheat, barley, and rye.
Are peanuts the only food that can cause a severe reaction?
No, many foods can cause severe reactions.
What is the local response in an IgE mediated allergy?
It includes symptoms like itchiness and localized swelling.
What is added after the patient's serum in the RAST test?
Radiolabeled anti-human IgE antibody.
How many other foods can cause allergic reactions?
More than 160.
What occurs when enough cross-linking of IgE happens?
Mast cells explode with histamine and other inflammatory substances.
What is the primary function of the immune system?
To protect the body from foreign invaders.
What percentage of all Americans have food allergies?
4% (approximately 12 million).
What are some characteristics of proteins that cause food allergies?
They are heat-resistant, resistant to digestion/proteolysis, and resistant to extremes in pH.
What are some common signs and symptoms of a food allergy?
Itchiness, swelling of the tongue, vomiting, diarrhea, hives, trouble breathing, or low blood pressure.
What type of adverse reaction is food intolerance classified as?
Non-immune mediated.
Why is education important in allergy prevention?
To teach the general public about allergies and ways to prevent them.
What symptoms can occur during an allergic response?
Wheezing, sneezing, coughing, itchy eyes, runny nose, and shortness of breath.
What is the reaction pattern observed in patients allergic to eggs during food challenges?
Reaction pattern during double-blind, placebo-controlled food challenge.
How many patients were admitted with a physician-reported diagnosis of anaphylaxis over 11 years?
A total of 2,854 patients.
Which cells are persistently infiltrated during a chronic inflammatory response?
Mast cells, leukocytes, and dendritic cells.
What is anaphylaxis?
A serious allergic reaction that is rapid in onset and may cause death.
What is the prevalence of cow milk allergy in the US?
2.5%.
How does allergic inflammation affect tissue cells?
It affects epithelial cells and muscle cells, causing chronic structural changes.
What types of leukocytes migrate to the initial site during the late phase response?
Neutrophils, Lymphocytes, Eosinophils, Macrophages.
What type of T-cell is involved in IgE mediated allergy?
Th2 (a type of T-cell).
What happens during the late-phase of an allergic reaction?
Inflammatory response that occurs hours after the initial reaction.
What do B-cells produce in IgE mediated allergies?
IgE (Immunoglobulin E).
How are food allergies diagnosed?
Through medical history, skin tests, and blood tests.
Who organized the Hong Kong Allergy Association?
Patients with allergy, their caregivers, and medical professionals.
Can cooking foods make them less allergenic?
Yes, cooking can make foods less allergenic.
What triggers Celiac Disease?
Hypersensitivity to gluten found in wheat, barley, rye, and certain other grains.
What does the RAST test detect?
Specific IgE antibodies to suspected or known allergens.
What is the risk percentage of allergic reactions to shellfish?
75%.
What is anaphylaxis in the context of allergic reactions?
Anaphylaxis is a severe, potentially life-threatening allergic reaction.
What does the amount of radioactivity indicate in the RAST test?
It is proportional to the serum IgE for the allergen.
Can foods contain multiple allergens?
Yes, foods can have one or many allergens in them.
What is angioedema?
A cutaneous symptom characterized by swelling beneath the skin.
Can Celiac Disease be asymptomatic?
Yes, it can be potentially asymptomatic.
What is the prevalence of celiac disease in Europe?
5 million people.
What are antibodies?
Proteins produced by B-cells that help identify and neutralize foreign objects like bacteria and viruses.
What is the prevalence of egg allergy in the US?
1.3%.
What respiratory symptom is associated with IgE-mediated reactions?
Rhinitis.
What is the prevalence of peanut allergy in the US?
0.8%.
What is laryngeal edema?
Swelling in the larynx, a respiratory symptom of IgE-mediated reactions.
What is a drawback of the Skin Prick Test?
It has a high false positive rate.
What are allergenic foods?
Foods that can trigger allergic reactions in susceptible individuals.
What happens to blood vessels during an acute allergic response?
Vasodilation and increased vascular permeability occur.
What occurs during the sensitization stage?
Production of IgE and binding of IgE to Mast cells.
What happens during mast cell activation?
Allergen binds to IgE on Mast cells, triggering the release of mediators.
What are some prevention strategies for food allergies?
Early introduction of allergenic foods and breastfeeding.
What is the risk of allergy in infants fed with intact cow's milk protein during the first week of life?
5-15%.
What is a systemic response in an allergic reaction?
A systemic response can include widespread symptoms like low blood pressure and throat swelling.
What are mediators in the context of mast cells?
Products released by mast cells that cause allergic symptoms.
How many people are affected by celiac disease in general?
1 in 133 people.
What is a symptom of the late phase response?
Further inflammation.
What are examples of other legumes that may cause allergic reactions?
Peas, lentils, beans.
Is it safe to have even one little bite of an allergenic food?
No, even one little bite is not okay.
Is there a cure for celiac disease?
No, there is no cure.
What are examples of other tree nuts that may cause allergic reactions?
Cashew, hazelnut.
What is anaphylaxis?
A severe, potentially life-threatening allergic reaction.
Can food allergies develop at any age?
Yes, they can develop at any age.
What is the risk of allergy in infants fed with intact cow's milk protein compared to breast-fed infants?
4 times higher in infants fed with intact cow's milk protein.
What is a characteristic feature of the small intestine in Celiac Disease?
Scalloping of folds and a 'cracked-mud' appearance.
What is the first step in the RAST test method?
The suspected allergen is bound to an insoluble material.
What is washed away after the binding process in the RAST test?
Unbound anti-human IgE antibodies.
What are food allergies?
Immune system reactions that occur after consuming certain foods.
What triggers food allergies?
Proteins in certain foods that the immune system mistakenly identifies as harmful.
