COMSAE ASA 110I- PHASE 1,
LEVEL 1 ACTUAL EXAM 2026-2027
COMLETE EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS
WITH RATIONALES (VERIFIED
ANSWERS) ALREADY GRADED
A+
ANSWER KEY PROVIDED
,Answer Key
.
Q# Ans Q# Ans Q# Ans Q# Ans Q# Ans
1. B 21. D 41. D 61. E 81. D
2. C 22. B 42. A 62. C 82. E
3. A 23. B 43. B 63. A 83. A
4. C 24. C 44. E 64. B 84. B
5. A 25. E 45. B 65. A 85. D
6. D 26. B 46. A 66. E 86. A
7. A 27. C 47. C 67. A 87. D
8. A 28. D 48. D 68. A 88. C
9. E 29. A 49. D 69. A 89. A
10. A 30. C 50. B 70. A 90. E
11. E 31. C 51. A 71. A 91. E
12. B 32. B 52. B 72. B 92. A
13. C 33. E 53. E 73. C 93. E
14. E 34. D 54. D 74. D 94. D
15. A 35. E 55. C 75. E 95. C
16. B 36. C 56. B 76. D 96. E
17. D 37. C 57. D 77. C 97. C
18. B 38. A 58. B 78. E 98. B
19. E 39. B 59. D 79. D 99. D
20. C 40. E 60. D 80. B 100. E
,Practice Questions with Rationales
1. An 8-year-old boy develops a facial rash described as 'slapped cheeks' followed several
days later by joint pain in his knees. His mother, who is 10 weeks pregnant, is concerned
about exposure. Which of the following structural proteins does the causative virus use to
bind host erythroid precursor cells?
A. Sialic acid residues on respiratory epithelium
B. P antigen (globoside) receptor on erythroid progenitor cells
C. Nicotinic acetylcholine receptor
D. ACE2 receptor
E. CD4 receptor
Correct Answer: B. P antigen (globoside) receptor on erythroid progenitor cells
Rationale:
Parvovirus B19 binds to the P antigen (globoside), a glycolipid receptor expressed on erythroid
progenitor cells in the bone marrow, which explains its tropism for these cells and its ability to
cause transient aplastic crisis in patients with underlying hemolytic conditions (such as sickle
cell disease) and hydrops fetalis in fetal infection, since fetal erythropoiesis is particularly
vulnerable. ACE2 is the receptor for SARS-CoV-2, unrelated to parvovirus B19. CD4 is the
primary receptor for HIV. Sialic acid residues are used as receptors by influenza virus for
respiratory epithelial binding. Nicotinic acetylcholine receptors are not viral receptors relevant to
this scenario; they are relevant to neuromuscular pharmacology and toxins like botulinum toxin.
2. A 32-year-old woman in her third trimester of pregnancy presents with severe headache,
visual disturbances, and a blood pressure of 165/110 mmHg. Urinalysis shows significant
proteinuria. Which of the following best describes the underlying pathophysiology of this
condition?
A. Pre-existing chronic hypertension unrelated to pregnancy
B. Autoimmune destruction of glomerular basement membrane
C. Abnormal placental vascularization leading to endothelial dysfunction and
systemic vasospasm
D. Acute fatty liver of pregnancy causing hepatic failure
E. Gestational diabetes causing vascular damage
Correct Answer: C. Abnormal placental vascularization leading to endothelial
dysfunction and systemic vasospasm
Rationale:
Preeclampsia is thought to result from abnormal placental implantation and vascularization
(inadequate trophoblastic invasion of maternal spiral arteries), leading to placental ischemia,
release of antiangiogenic factors, widespread endothelial dysfunction, and systemic vasospasm,
producing hypertension, proteinuria, and end-organ effects such as headache and visual
disturbances (cerebral vasospasm/edema). It is not primarily an autoimmune glomerular
basement membrane process (that would describe conditions like anti-GBM disease). The new
onset of hypertension and proteinuria in the third trimester, rather than predating pregnancy,
argues against pre-existing chronic hypertension as the primary process here. Gestational
diabetes is a separate metabolic condition not directly causing this acute hypertensive,
, proteinuric presentation. Acute fatty liver of pregnancy presents with hepatic dysfunction,
hypoglycemia, and coagulopathy, a distinct (though sometimes overlapping) entity from
preeclampsia.
3. A 6-year-old boy presents with periorbital edema, proteinuria of 4 g/day,
hypoalbuminemia, and hyperlipidemia. Renal biopsy under light microscopy appears
normal, but electron microscopy shows diffuse effacement of podocyte foot processes.
Which of the following is the most likely diagnosis?
A. Minimal change disease
B. Membranous nephropathy
C. IgA nephropathy
D. Diffuse proliferative glomerulonephritis
E. Focal segmental glomerulosclerosis
Correct Answer: A. Minimal change disease
Rationale:
Minimal change disease is the most common cause of nephrotic syndrome in children and
classically shows normal glomeruli on light microscopy with diffuse podocyte foot process
effacement seen only on electron microscopy. It typically responds well to corticosteroids. Focal
segmental glomerulosclerosis would show segmental sclerosis on light microscopy.
Membranous nephropathy shows diffuse capillary wall thickening with subepithelial deposits
('spike and dome' pattern) on electron microscopy, more common in adults. Diffuse proliferative
glomerulonephritis shows hypercellularity and is associated with lupus nephritis, presenting with
a nephritic, not purely nephrotic, picture. IgA nephropathy shows mesangial IgA deposits and
typically presents with episodic hematuria following mucosal infections.
4. A 55-year-old man with a history of chronic alcohol use presents with confusion, ataxia,
and ophthalmoplegia. He is given thiamine before glucose is administered. Which of the
following enzymes is most directly affected by thiamine deficiency, contributing to this
presentation?
A. Phosphofructokinase
B. Glycogen phosphorylase
C. Alpha-ketoglutarate dehydrogenase
D. Hexokinase
E. Glucose-6-phosphate dehydrogenase
Correct Answer: C. Alpha-ketoglutarate dehydrogenase
Rationale:
Thiamine (vitamin B1) is a cofactor for several key enzymes, including alpha-ketoglutarate
dehydrogenase (in the TCA cycle), pyruvate dehydrogenase, transketolase (in the pentose
phosphate pathway), and branched-chain alpha-ketoacid dehydrogenase. Deficiency impairs
cellular energy metabolism, particularly in highly metabolically active tissues like neurons,
leading to Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia) in chronic alcohol
users who have poor thiamine intake and absorption. Administering glucose without first
replenishing thiamine can precipitate or worsen Wernicke encephalopathy by further consuming
LEVEL 1 ACTUAL EXAM 2026-2027
COMLETE EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS
WITH RATIONALES (VERIFIED
ANSWERS) ALREADY GRADED
A+
ANSWER KEY PROVIDED
,Answer Key
.
Q# Ans Q# Ans Q# Ans Q# Ans Q# Ans
1. B 21. D 41. D 61. E 81. D
2. C 22. B 42. A 62. C 82. E
3. A 23. B 43. B 63. A 83. A
4. C 24. C 44. E 64. B 84. B
5. A 25. E 45. B 65. A 85. D
6. D 26. B 46. A 66. E 86. A
7. A 27. C 47. C 67. A 87. D
8. A 28. D 48. D 68. A 88. C
9. E 29. A 49. D 69. A 89. A
10. A 30. C 50. B 70. A 90. E
11. E 31. C 51. A 71. A 91. E
12. B 32. B 52. B 72. B 92. A
13. C 33. E 53. E 73. C 93. E
14. E 34. D 54. D 74. D 94. D
15. A 35. E 55. C 75. E 95. C
16. B 36. C 56. B 76. D 96. E
17. D 37. C 57. D 77. C 97. C
18. B 38. A 58. B 78. E 98. B
19. E 39. B 59. D 79. D 99. D
20. C 40. E 60. D 80. B 100. E
,Practice Questions with Rationales
1. An 8-year-old boy develops a facial rash described as 'slapped cheeks' followed several
days later by joint pain in his knees. His mother, who is 10 weeks pregnant, is concerned
about exposure. Which of the following structural proteins does the causative virus use to
bind host erythroid precursor cells?
A. Sialic acid residues on respiratory epithelium
B. P antigen (globoside) receptor on erythroid progenitor cells
C. Nicotinic acetylcholine receptor
D. ACE2 receptor
E. CD4 receptor
Correct Answer: B. P antigen (globoside) receptor on erythroid progenitor cells
Rationale:
Parvovirus B19 binds to the P antigen (globoside), a glycolipid receptor expressed on erythroid
progenitor cells in the bone marrow, which explains its tropism for these cells and its ability to
cause transient aplastic crisis in patients with underlying hemolytic conditions (such as sickle
cell disease) and hydrops fetalis in fetal infection, since fetal erythropoiesis is particularly
vulnerable. ACE2 is the receptor for SARS-CoV-2, unrelated to parvovirus B19. CD4 is the
primary receptor for HIV. Sialic acid residues are used as receptors by influenza virus for
respiratory epithelial binding. Nicotinic acetylcholine receptors are not viral receptors relevant to
this scenario; they are relevant to neuromuscular pharmacology and toxins like botulinum toxin.
2. A 32-year-old woman in her third trimester of pregnancy presents with severe headache,
visual disturbances, and a blood pressure of 165/110 mmHg. Urinalysis shows significant
proteinuria. Which of the following best describes the underlying pathophysiology of this
condition?
A. Pre-existing chronic hypertension unrelated to pregnancy
B. Autoimmune destruction of glomerular basement membrane
C. Abnormal placental vascularization leading to endothelial dysfunction and
systemic vasospasm
D. Acute fatty liver of pregnancy causing hepatic failure
E. Gestational diabetes causing vascular damage
Correct Answer: C. Abnormal placental vascularization leading to endothelial
dysfunction and systemic vasospasm
Rationale:
Preeclampsia is thought to result from abnormal placental implantation and vascularization
(inadequate trophoblastic invasion of maternal spiral arteries), leading to placental ischemia,
release of antiangiogenic factors, widespread endothelial dysfunction, and systemic vasospasm,
producing hypertension, proteinuria, and end-organ effects such as headache and visual
disturbances (cerebral vasospasm/edema). It is not primarily an autoimmune glomerular
basement membrane process (that would describe conditions like anti-GBM disease). The new
onset of hypertension and proteinuria in the third trimester, rather than predating pregnancy,
argues against pre-existing chronic hypertension as the primary process here. Gestational
diabetes is a separate metabolic condition not directly causing this acute hypertensive,
, proteinuric presentation. Acute fatty liver of pregnancy presents with hepatic dysfunction,
hypoglycemia, and coagulopathy, a distinct (though sometimes overlapping) entity from
preeclampsia.
3. A 6-year-old boy presents with periorbital edema, proteinuria of 4 g/day,
hypoalbuminemia, and hyperlipidemia. Renal biopsy under light microscopy appears
normal, but electron microscopy shows diffuse effacement of podocyte foot processes.
Which of the following is the most likely diagnosis?
A. Minimal change disease
B. Membranous nephropathy
C. IgA nephropathy
D. Diffuse proliferative glomerulonephritis
E. Focal segmental glomerulosclerosis
Correct Answer: A. Minimal change disease
Rationale:
Minimal change disease is the most common cause of nephrotic syndrome in children and
classically shows normal glomeruli on light microscopy with diffuse podocyte foot process
effacement seen only on electron microscopy. It typically responds well to corticosteroids. Focal
segmental glomerulosclerosis would show segmental sclerosis on light microscopy.
Membranous nephropathy shows diffuse capillary wall thickening with subepithelial deposits
('spike and dome' pattern) on electron microscopy, more common in adults. Diffuse proliferative
glomerulonephritis shows hypercellularity and is associated with lupus nephritis, presenting with
a nephritic, not purely nephrotic, picture. IgA nephropathy shows mesangial IgA deposits and
typically presents with episodic hematuria following mucosal infections.
4. A 55-year-old man with a history of chronic alcohol use presents with confusion, ataxia,
and ophthalmoplegia. He is given thiamine before glucose is administered. Which of the
following enzymes is most directly affected by thiamine deficiency, contributing to this
presentation?
A. Phosphofructokinase
B. Glycogen phosphorylase
C. Alpha-ketoglutarate dehydrogenase
D. Hexokinase
E. Glucose-6-phosphate dehydrogenase
Correct Answer: C. Alpha-ketoglutarate dehydrogenase
Rationale:
Thiamine (vitamin B1) is a cofactor for several key enzymes, including alpha-ketoglutarate
dehydrogenase (in the TCA cycle), pyruvate dehydrogenase, transketolase (in the pentose
phosphate pathway), and branched-chain alpha-ketoacid dehydrogenase. Deficiency impairs
cellular energy metabolism, particularly in highly metabolically active tissues like neurons,
leading to Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia) in chronic alcohol
users who have poor thiamine intake and absorption. Administering glucose without first
replenishing thiamine can precipitate or worsen Wernicke encephalopathy by further consuming
