ABM in Allergy and Immunology Practice Exam
Question 1: Which type of immunity is present at birth and acts as the first line of defense against
pathogens?
A. Adaptive immunity
B. Innate immunity
C. Humoral immunity
D. Cell-mediated immunity
Answer: B
Explanation: Innate immunity is non-specific, present at birth, and provides immediate defense against
pathogens without prior exposure.
Question 2: Which immunoglobulin is primarily associated with allergic reactions?
A. IgA
B. IgG
C. IgE
D. IgM
Answer: C
Explanation: IgE mediates allergic reactions by binding to allergens and triggering mast cell
degranulation.
Question 3: What is the main function of histamine in an allergic reaction?
A. Inhibits cytokine production
B. Causes vasoconstriction
C. Increases vascular permeability and induces smooth muscle contraction
D. Enhances antibody production
Answer: C
Explanation: Histamine released during allergic reactions increases vascular permeability and causes
smooth muscle contraction, leading to symptoms like edema and bronchoconstriction.
Question 4: Which of the following is a characteristic feature of Type I hypersensitivity reactions?
A. Delayed cell-mediated response
B. Antibody-mediated cytotoxicity
C. IgE-mediated immediate reaction
D. Immune complex deposition
Answer: C
Explanation: Type I hypersensitivity reactions are IgE-mediated and occur immediately upon exposure to
the allergen.
Question 5: Which cell type plays a central role in releasing mediators during an allergic reaction?
A. Neutrophils
B. Mast cells
C. Lymphocytes
D. Monocytes
Answer: B
Explanation: Mast cells are key in releasing histamine and other mediators during an allergic response.
,Question 6: What distinguishes innate immunity from adaptive immunity?
A. Innate immunity is antigen-specific while adaptive is non-specific.
B. Innate immunity provides a delayed response while adaptive immunity is immediate.
C. Innate immunity is present at birth and non-specific, whereas adaptive immunity develops over time
and is specific.
D. Adaptive immunity uses phagocytosis exclusively.
Answer: C
Explanation: Innate immunity is non-specific and present at birth, while adaptive immunity is specific
and develops after exposure to antigens.
Question 7: Which of the following immunoglobulins is most abundant in serum?
A. IgA
B. IgD
C. IgE
D. IgG
Answer: D
Explanation: IgG is the most abundant immunoglobulin in the serum and plays a major role in the
secondary immune response.
Question 8: What role do cytokines play in allergic reactions?
A. They directly kill pathogens.
B. They mediate communication between immune cells and amplify the inflammatory response.
C. They are involved in antibody production.
D. They are responsible for phagocytosis.
Answer: B
Explanation: Cytokines facilitate cell signaling in the immune system, amplifying the inflammatory
response during allergies.
Question 9: In the context of allergy, what is the significance of the late-phase reaction?
A. It is mediated by IgM antibodies.
B. It occurs immediately after allergen exposure.
C. It involves the recruitment of inflammatory cells leading to sustained symptoms.
D. It only occurs in autoimmune diseases.
Answer: C
Explanation: The late-phase reaction occurs hours after the initial allergen exposure, involving
inflammatory cell recruitment and prolonged symptoms.
Question 10: Which T cell subtype is primarily involved in maintaining immune tolerance?
A. Cytotoxic T cells
B. Helper T cells
C. Regulatory T cells (Tregs)
D. Memory T cells
Answer: C
Explanation: Regulatory T cells (Tregs) help maintain immune tolerance by suppressing excessive
immune responses.
,Question 11: Which condition is characterized by seasonal symptoms due to airborne allergens like
pollen?
A. Allergic rhinitis
B. Asthma
C. Atopic dermatitis
D. Food allergy
Answer: A
Explanation: Allergic rhinitis, particularly the seasonal form, is often triggered by airborne allergens such
as pollen.
Question 12: What is the primary mechanism behind occupational asthma?
A. Viral infection
B. Allergic reaction to workplace substances
C. Genetic mutation
D. Autoimmune destruction
Answer: B
Explanation: Occupational asthma is often caused by exposure to allergens or irritants in the workplace.
Question 13: Which of the following best describes atopic dermatitis?
A. A respiratory allergic reaction
B. A chronic inflammatory skin condition with an allergic component
C. An acute food allergy reaction
D. A type of contact dermatitis
Answer: B
Explanation: Atopic dermatitis is a chronic inflammatory skin condition with an allergic component,
often seen in patients with other atopic diseases.
Question 14: Which type of allergy is associated with immediate reactions after ingestion of certain
foods?
A. Contact dermatitis
B. Delayed hypersensitivity
C. Food allergy
D. Autoimmune reaction
Answer: C
Explanation: Food allergies cause immediate hypersensitivity reactions after ingestion of the allergen.
Question 15: What is the key difference between skin prick tests and intradermal tests in allergy
diagnosis?
A. Skin prick tests are more invasive.
B. Intradermal tests are more sensitive than skin prick tests.
C. Skin prick tests measure delayed hypersensitivity reactions.
D. Intradermal tests do not require allergen extracts.
Answer: B
Explanation: Intradermal tests are more sensitive compared to skin prick tests, although they carry a
higher risk of systemic reactions.
, Question 16: Which laboratory test is most useful for quantifying total IgE levels in the serum?
A. Skin prick test
B. RAST
C. Total IgE assay
D. Spirometry
Answer: C
Explanation: A total IgE assay measures the overall concentration of IgE in the serum and can indicate
atopic status.
Question 17: What is the purpose of the methacholine challenge test?
A. To assess skin reactivity
B. To evaluate airway hyperresponsiveness in suspected asthma
C. To measure IgE levels
D. To test for food allergies
Answer: B
Explanation: The methacholine challenge test is used to assess airway hyperresponsiveness, which is a
hallmark of asthma.
Question 18: Which imaging modality is often used to evaluate sinus involvement in allergic rhinitis?
A. MRI
B. Ultrasound
C. Sinus CT scan
D. X-ray of the extremities
Answer: C
Explanation: A sinus CT scan provides detailed images of the sinus anatomy and is useful in evaluating
sinusitis associated with allergic rhinitis.
Question 19: What is the role of leukotriene receptor antagonists in the management of allergic
diseases?
A. They block the action of histamine.
B. They inhibit the synthesis of prostaglandins.
C. They block the effects of leukotrienes involved in inflammation.
D. They stimulate IgE production.
Answer: C
Explanation: Leukotriene receptor antagonists block the action of leukotrienes, reducing inflammation
and bronchoconstriction in allergic conditions such as asthma.
Question 20: Which treatment is most effective in providing long-term relief for patients with allergic
rhinitis?
A. Oral antihistamines
B. Intranasal corticosteroids
C. Decongestants
D. Antibiotics
Answer: B
Explanation: Intranasal corticosteroids are considered the most effective long-term treatment for
controlling the inflammation associated with allergic rhinitis.
Question 1: Which type of immunity is present at birth and acts as the first line of defense against
pathogens?
A. Adaptive immunity
B. Innate immunity
C. Humoral immunity
D. Cell-mediated immunity
Answer: B
Explanation: Innate immunity is non-specific, present at birth, and provides immediate defense against
pathogens without prior exposure.
Question 2: Which immunoglobulin is primarily associated with allergic reactions?
A. IgA
B. IgG
C. IgE
D. IgM
Answer: C
Explanation: IgE mediates allergic reactions by binding to allergens and triggering mast cell
degranulation.
Question 3: What is the main function of histamine in an allergic reaction?
A. Inhibits cytokine production
B. Causes vasoconstriction
C. Increases vascular permeability and induces smooth muscle contraction
D. Enhances antibody production
Answer: C
Explanation: Histamine released during allergic reactions increases vascular permeability and causes
smooth muscle contraction, leading to symptoms like edema and bronchoconstriction.
Question 4: Which of the following is a characteristic feature of Type I hypersensitivity reactions?
A. Delayed cell-mediated response
B. Antibody-mediated cytotoxicity
C. IgE-mediated immediate reaction
D. Immune complex deposition
Answer: C
Explanation: Type I hypersensitivity reactions are IgE-mediated and occur immediately upon exposure to
the allergen.
Question 5: Which cell type plays a central role in releasing mediators during an allergic reaction?
A. Neutrophils
B. Mast cells
C. Lymphocytes
D. Monocytes
Answer: B
Explanation: Mast cells are key in releasing histamine and other mediators during an allergic response.
,Question 6: What distinguishes innate immunity from adaptive immunity?
A. Innate immunity is antigen-specific while adaptive is non-specific.
B. Innate immunity provides a delayed response while adaptive immunity is immediate.
C. Innate immunity is present at birth and non-specific, whereas adaptive immunity develops over time
and is specific.
D. Adaptive immunity uses phagocytosis exclusively.
Answer: C
Explanation: Innate immunity is non-specific and present at birth, while adaptive immunity is specific
and develops after exposure to antigens.
Question 7: Which of the following immunoglobulins is most abundant in serum?
A. IgA
B. IgD
C. IgE
D. IgG
Answer: D
Explanation: IgG is the most abundant immunoglobulin in the serum and plays a major role in the
secondary immune response.
Question 8: What role do cytokines play in allergic reactions?
A. They directly kill pathogens.
B. They mediate communication between immune cells and amplify the inflammatory response.
C. They are involved in antibody production.
D. They are responsible for phagocytosis.
Answer: B
Explanation: Cytokines facilitate cell signaling in the immune system, amplifying the inflammatory
response during allergies.
Question 9: In the context of allergy, what is the significance of the late-phase reaction?
A. It is mediated by IgM antibodies.
B. It occurs immediately after allergen exposure.
C. It involves the recruitment of inflammatory cells leading to sustained symptoms.
D. It only occurs in autoimmune diseases.
Answer: C
Explanation: The late-phase reaction occurs hours after the initial allergen exposure, involving
inflammatory cell recruitment and prolonged symptoms.
Question 10: Which T cell subtype is primarily involved in maintaining immune tolerance?
A. Cytotoxic T cells
B. Helper T cells
C. Regulatory T cells (Tregs)
D. Memory T cells
Answer: C
Explanation: Regulatory T cells (Tregs) help maintain immune tolerance by suppressing excessive
immune responses.
,Question 11: Which condition is characterized by seasonal symptoms due to airborne allergens like
pollen?
A. Allergic rhinitis
B. Asthma
C. Atopic dermatitis
D. Food allergy
Answer: A
Explanation: Allergic rhinitis, particularly the seasonal form, is often triggered by airborne allergens such
as pollen.
Question 12: What is the primary mechanism behind occupational asthma?
A. Viral infection
B. Allergic reaction to workplace substances
C. Genetic mutation
D. Autoimmune destruction
Answer: B
Explanation: Occupational asthma is often caused by exposure to allergens or irritants in the workplace.
Question 13: Which of the following best describes atopic dermatitis?
A. A respiratory allergic reaction
B. A chronic inflammatory skin condition with an allergic component
C. An acute food allergy reaction
D. A type of contact dermatitis
Answer: B
Explanation: Atopic dermatitis is a chronic inflammatory skin condition with an allergic component,
often seen in patients with other atopic diseases.
Question 14: Which type of allergy is associated with immediate reactions after ingestion of certain
foods?
A. Contact dermatitis
B. Delayed hypersensitivity
C. Food allergy
D. Autoimmune reaction
Answer: C
Explanation: Food allergies cause immediate hypersensitivity reactions after ingestion of the allergen.
Question 15: What is the key difference between skin prick tests and intradermal tests in allergy
diagnosis?
A. Skin prick tests are more invasive.
B. Intradermal tests are more sensitive than skin prick tests.
C. Skin prick tests measure delayed hypersensitivity reactions.
D. Intradermal tests do not require allergen extracts.
Answer: B
Explanation: Intradermal tests are more sensitive compared to skin prick tests, although they carry a
higher risk of systemic reactions.
, Question 16: Which laboratory test is most useful for quantifying total IgE levels in the serum?
A. Skin prick test
B. RAST
C. Total IgE assay
D. Spirometry
Answer: C
Explanation: A total IgE assay measures the overall concentration of IgE in the serum and can indicate
atopic status.
Question 17: What is the purpose of the methacholine challenge test?
A. To assess skin reactivity
B. To evaluate airway hyperresponsiveness in suspected asthma
C. To measure IgE levels
D. To test for food allergies
Answer: B
Explanation: The methacholine challenge test is used to assess airway hyperresponsiveness, which is a
hallmark of asthma.
Question 18: Which imaging modality is often used to evaluate sinus involvement in allergic rhinitis?
A. MRI
B. Ultrasound
C. Sinus CT scan
D. X-ray of the extremities
Answer: C
Explanation: A sinus CT scan provides detailed images of the sinus anatomy and is useful in evaluating
sinusitis associated with allergic rhinitis.
Question 19: What is the role of leukotriene receptor antagonists in the management of allergic
diseases?
A. They block the action of histamine.
B. They inhibit the synthesis of prostaglandins.
C. They block the effects of leukotrienes involved in inflammation.
D. They stimulate IgE production.
Answer: C
Explanation: Leukotriene receptor antagonists block the action of leukotrienes, reducing inflammation
and bronchoconstriction in allergic conditions such as asthma.
Question 20: Which treatment is most effective in providing long-term relief for patients with allergic
rhinitis?
A. Oral antihistamines
B. Intranasal corticosteroids
C. Decongestants
D. Antibiotics
Answer: B
Explanation: Intranasal corticosteroids are considered the most effective long-term treatment for
controlling the inflammation associated with allergic rhinitis.
