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JACI Primer EXAM NEWEST 2025/2026 ACTUAL EXAM QUESTIONS
AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |A+
GRADED
Question 1. Which of the following statements concerning severe combined
immunodeficiency (SCID) is true?
A. SCID is characterized by severe deficiency of T cells.
B. SCID is characterized by severe deficiency of T and B cells.
C. SCID is characterized by severe deficiency of T, B, and natural killer cells.
D. SCID is characterized by severe deficiency of both lymphocytes and
neutrophils. - ANSWER-1. Answer: A
Explanation: SCID includes a heterogeneous group of disorders
characterized by severe defects in T-cell development. Some (but not
all) forms of SCID also have defects in B-cell development, natural killer
cell development, or both, whereas impaired myeloid differentiation is
restricted to a few rare forms of SCID. Regardless of the presence or
absence of B cells, patients with SCID have a severe defect in antibody
production, reflecting a lack of T lymphocytes.
Question 2. Which of the following statements concerning X- linked
agammaglobulinemia (XLA) is true?
A. XLA is characterized by lack of immunoglobulins in spite of a normal
number of circulating B cells.
B. XLA is characterized by a virtual lack of circulating B cells.
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C. In patients with XLA, the profound deficiency of immunoglobulins reflects
defects of TH lymphocytes.
D. The mainstay of treatment of patients with XLA is antibiotic prophylaxis. -
ANSWER-2. Answer: B
Explanation: XLA and all other forms of congenital
agammaglobulinemia are caused by genetic defects that affect
signaling through the pre-B-cell receptor in the bone marrow. Therefore
patients with congenital agammaglobulinemia typically lack circulating
mature B cells.
Question 3. Which of the following presentations is common in patients with
chronic granulomatous disease?
A. autoimmune manifestations resembling systemic lupus erythematosus
B. interstitial pneumonia caused by Pneumocystis jiroveci
C. purulent lymphadenitis
D. recurrent otitis media - ANSWER-3. Answer: C
Explanation: Neutrophils are important in the defense against bacteria
and fungi. Patients with neutrophil defects often present with severe
infections, among which purulent lymphadenitis is common.
Question 4. Which of the following statements concerning treat- ment with
immunoglobulins is true?
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A. Initial treatment for patients with agammaglobulinemia should be with
intravenous immunoglobulin, 100 mg/kg every 3 weeks.
B. Subcutaneous immunoglobulins should be used at the dose of 100
mg/kg/wk in children less than 14 years of age. Beyond that age, the dose
for adults is 4 g/wk.
C. The usual dose for subcutaneous immunoglobulins is 100 mg/kg/wk.
D. Patients with IgA deficiency should receive preparations enriched in IgA.
- ANSWER-4. Answer: C
Explanation: It is important that patients with antibody deficiency
receive appropriate replacement treatment. This is usually achieved
with 400 mg/kg/mo intravenous immunoglobulins or with weekly
injections of subcutaneous immunoglobulins at a dose of 100 mg/kg/
wk. This regimen applies to patients of any age.
Question 5. An 18-year-old woman presents with a history of recurrent
respiratory tract infections in the past 3 months. She has been previously
healthy. Which of the following is the most likely cause of immunodeficiency
in this patient?
A. severe combined immunodeficiency
B. HIV infection
C. X-linked agammaglobulinemia
D. hyper-IgM syndrome - ANSWER-1. Answer: B
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Explanation: From the 4 options, option B is the most likely answer.
HIV infection can be considered as a cause of immunodeficiency at any
age. Options A, C, and D are primary immunodeficiencies that present
clinically in infancy or early childhood.
Question 6. Which of the following is a characteristic of a sec- ondary
immunodeficiency?
A. The clinical presentation is variable.
B. A defect in T-cell function can always be identified.
C. Management should prioritize immunoglobulin supplementation in all
cases.
D. Phagocyte chemotaxis is normal. - ANSWER-2. Answer: A
Explanation: Secondary immunodeficiencies have a variable clinical
presentation. T-cell, B-cell, or innate immunity components, including
phagocyte function, might or might not be affected. Management
should include immunoglobulin supplementation only if humoral
responses are not restored despite optimal control of the primary
disease.
Question 7. Calcineurin inhibitors primarily inhibit—
A. oxidative burst.
B. complement activation.
C. T-cell activation.
JACI Primer EXAM NEWEST 2025/2026 ACTUAL EXAM QUESTIONS
AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |A+
GRADED
Question 1. Which of the following statements concerning severe combined
immunodeficiency (SCID) is true?
A. SCID is characterized by severe deficiency of T cells.
B. SCID is characterized by severe deficiency of T and B cells.
C. SCID is characterized by severe deficiency of T, B, and natural killer cells.
D. SCID is characterized by severe deficiency of both lymphocytes and
neutrophils. - ANSWER-1. Answer: A
Explanation: SCID includes a heterogeneous group of disorders
characterized by severe defects in T-cell development. Some (but not
all) forms of SCID also have defects in B-cell development, natural killer
cell development, or both, whereas impaired myeloid differentiation is
restricted to a few rare forms of SCID. Regardless of the presence or
absence of B cells, patients with SCID have a severe defect in antibody
production, reflecting a lack of T lymphocytes.
Question 2. Which of the following statements concerning X- linked
agammaglobulinemia (XLA) is true?
A. XLA is characterized by lack of immunoglobulins in spite of a normal
number of circulating B cells.
B. XLA is characterized by a virtual lack of circulating B cells.
,2|Page
C. In patients with XLA, the profound deficiency of immunoglobulins reflects
defects of TH lymphocytes.
D. The mainstay of treatment of patients with XLA is antibiotic prophylaxis. -
ANSWER-2. Answer: B
Explanation: XLA and all other forms of congenital
agammaglobulinemia are caused by genetic defects that affect
signaling through the pre-B-cell receptor in the bone marrow. Therefore
patients with congenital agammaglobulinemia typically lack circulating
mature B cells.
Question 3. Which of the following presentations is common in patients with
chronic granulomatous disease?
A. autoimmune manifestations resembling systemic lupus erythematosus
B. interstitial pneumonia caused by Pneumocystis jiroveci
C. purulent lymphadenitis
D. recurrent otitis media - ANSWER-3. Answer: C
Explanation: Neutrophils are important in the defense against bacteria
and fungi. Patients with neutrophil defects often present with severe
infections, among which purulent lymphadenitis is common.
Question 4. Which of the following statements concerning treat- ment with
immunoglobulins is true?
,3|Page
A. Initial treatment for patients with agammaglobulinemia should be with
intravenous immunoglobulin, 100 mg/kg every 3 weeks.
B. Subcutaneous immunoglobulins should be used at the dose of 100
mg/kg/wk in children less than 14 years of age. Beyond that age, the dose
for adults is 4 g/wk.
C. The usual dose for subcutaneous immunoglobulins is 100 mg/kg/wk.
D. Patients with IgA deficiency should receive preparations enriched in IgA.
- ANSWER-4. Answer: C
Explanation: It is important that patients with antibody deficiency
receive appropriate replacement treatment. This is usually achieved
with 400 mg/kg/mo intravenous immunoglobulins or with weekly
injections of subcutaneous immunoglobulins at a dose of 100 mg/kg/
wk. This regimen applies to patients of any age.
Question 5. An 18-year-old woman presents with a history of recurrent
respiratory tract infections in the past 3 months. She has been previously
healthy. Which of the following is the most likely cause of immunodeficiency
in this patient?
A. severe combined immunodeficiency
B. HIV infection
C. X-linked agammaglobulinemia
D. hyper-IgM syndrome - ANSWER-1. Answer: B
, 4|Page
Explanation: From the 4 options, option B is the most likely answer.
HIV infection can be considered as a cause of immunodeficiency at any
age. Options A, C, and D are primary immunodeficiencies that present
clinically in infancy or early childhood.
Question 6. Which of the following is a characteristic of a sec- ondary
immunodeficiency?
A. The clinical presentation is variable.
B. A defect in T-cell function can always be identified.
C. Management should prioritize immunoglobulin supplementation in all
cases.
D. Phagocyte chemotaxis is normal. - ANSWER-2. Answer: A
Explanation: Secondary immunodeficiencies have a variable clinical
presentation. T-cell, B-cell, or innate immunity components, including
phagocyte function, might or might not be affected. Management
should include immunoglobulin supplementation only if humoral
responses are not restored despite optimal control of the primary
disease.
Question 7. Calcineurin inhibitors primarily inhibit—
A. oxidative burst.
B. complement activation.
C. T-cell activation.
