Quick revision: every question with its correct answer. For the full explanation, open the test and tap View Solution.
8.4 Immunodeficiencies — Test 1
Q1. Immunodeficiencies are classified as primary or secondary, where primary means:✓ Inherited/genetic defects of the immune system
Q2. Severe combined immunodeficiency (SCID) is characterised by:✓ Defects affecting both T and B cell (adaptive) immunity
Q3. X-linked (Bruton) agammaglobulinaemia results from a defect in:✓ B-cell development (BTK), causing very low antibody
Q4. DiGeorge syndrome results from:✓ Thymic hypoplasia/aplasia causing T-cell deficiency
Q5. Chronic granulomatous disease (CGD) is caused by a defect in:✓ The phagocyte NADPH oxidase (respiratory burst)
Q6. The most common secondary (acquired) immunodeficiency worldwide is due to:✓ HIV infection (AIDS)
Q7. A patient with a pure antibody (B-cell) deficiency is especially susceptible to:✓ Recurrent pyogenic (encapsulated) bacterial infections
Q8. A patient with a T-cell deficiency is especially susceptible to:✓ Viral, fungal and intracellular infections
Q9. Complement deficiencies, particularly of early components (e.g. C1–C4), are associated with:✓ Immune-complex disease (lupus-like) and pyogenic infections
Q10. Deficiency of the late complement components (C5–C9, the membrane attack complex) characteristically predisposes to:✓ Recurrent Neisseria (meningococcal/gonococcal) infections
Q11. The defect in common X-linked SCID involves the:✓ Common γ-chain shared by several cytokine receptors
Q12. Wiskott-Aldrich syndrome classically presents with:✓ Eczema, thrombocytopenia and immunodeficiency
Q13. Selective IgA deficiency, the most common primary immunodeficiency, often presents with:✓ Mucosal/respiratory and gut infections (often mild) and possible transfusion reactions
Q14. A useful clue that an immunodeficiency is antibody-related rather than T-cell-related is:✓ Recurrent pyogenic bacterial infections after ~6 months of age
Q15. Leukocyte adhesion deficiency (LAD) impairs immunity because phagocytes cannot:✓ Adhere to endothelium and migrate into tissues
Q16. Live attenuated vaccines are generally contraindicated in patients with:✓ Severe T-cell immunodeficiency
Q17. A screening test historically used for chronic granulomatous disease is the:✓ Nitroblue tetrazolium (NBT) / DHR test of the respiratory burst
Q18. Hyper-IgM syndrome (CD40L deficiency) results in:✓ High IgM but low IgG/IgA/IgE due to failed class switching
Q19. Bone-marrow (haematopoietic stem cell) transplantation can be curative for:✓ Severe combined immunodeficiency (SCID)
Q20. DiGeorge syndrome is caused by:✓ Deletion on chromosome 22 (causing thymic aplasia)
Q21. Severe combined immunodeficiency (SCID) is characterised by:✓ Non-functional both B and T cells
Q22. Nude (athymic) mice are characterised by:✓ Absence of the thymus and a greatly reduced number of T cells
Q23. Match each immunodeficiency with its defect and select the correct option.✓ A-iii, B-i, C-ii, D-iv