COMSAE Phase 1 Exam Form 114
Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. The most common cause of community-acquired pneumonia in
adults is:
A. Haemophilus influenzae
B. Mycoplasma pneumoniae
C. Streptococcus pneumoniae
D. Staphylococcus aureus
Rationale: Streptococcus pneumoniae is the leading cause of
community-acquired pneumonia in adults worldwide due to its
prevalence and pathogenicity. Mycoplasma pneumoniae is more
common in younger patients.
2. A 5-year-old child presents with fever, cough, and a barking cough.
The most likely diagnosis is:
, A. Asthma
B. Croup (laryngotracheobronchitis)
C. Bronchiolitis
D. Epiglottitis
Rationale: Croup typically presents with a barking cough, stridor, and
fever in children aged 6 months to 5 years. Asthma usually presents
with wheezing without stridor.
3. The primary mechanism of action of beta-lactam antibiotics is:
A. Inhibition of protein synthesis
B. Inhibition of bacterial cell wall synthesis
C. Disruption of DNA replication
D. Inhibition of folate synthesis
Rationale: Beta-lactams, such as penicillins and cephalosporins, inhibit
transpeptidase enzymes, preventing cross-linking of peptidoglycan in
bacterial cell walls, leading to lysis.
4. The most appropriate initial test for suspected pulmonary
embolism is:
A. Chest X-ray
B. CT pulmonary angiography
C. D-dimer alone
D. MRI of the chest
,Rationale: CT pulmonary angiography is the gold standard for
diagnosing pulmonary embolism in stable patients, providing direct
visualization of thrombi in pulmonary arteries.
5. A patient with chronic alcoholism presents with confusion, ataxia,
and ophthalmoplegia. The most likely diagnosis is:
A. Hepatic encephalopathy
B. Stroke
C. Wernicke encephalopathy
D. Korsakoff syndrome
Rationale: Wernicke encephalopathy results from thiamine deficiency,
commonly in alcoholics, and presents with the classic triad: confusion,
ataxia, and ophthalmoplegia. Korsakoff syndrome involves chronic
memory impairment.
6. A 30-year-old woman presents with heat intolerance, weight loss,
and palpitations. Laboratory findings reveal low TSH and elevated
T3/T4. The most likely diagnosis is:
A. Hypothyroidism
B. Subclinical hypothyroidism
C. Hyperthyroidism (Graves’ disease likely)
D. Hashimoto thyroiditis
, Rationale: Hyperthyroidism presents with low TSH and high thyroid
hormones. Graves’ disease is the most common cause in adults,
characterized by diffuse goiter and sometimes ophthalmopathy.
7. The most common cause of hypothyroidism worldwide is:
A. Iodine deficiency
B. Hashimoto thyroiditis
C. Pituitary failure
D. Hashimoto thyroiditis
Rationale: In iodine-sufficient countries, Hashimoto thyroiditis is the
leading cause of hypothyroidism, an autoimmune destruction of the
thyroid gland.
8. A 65-year-old man presents with resting tremor, rigidity, and
bradykinesia. The most likely diagnosis is:
A. Essential tremor
B. Huntington disease
C. Parkinson disease
D. Multiple sclerosis
Rationale: Parkinson disease presents with the classic triad of resting
tremor, rigidity, and bradykinesia, typically in older adults.
9. The most appropriate initial therapy for anaphylaxis is:
A. Corticosteroids
Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. The most common cause of community-acquired pneumonia in
adults is:
A. Haemophilus influenzae
B. Mycoplasma pneumoniae
C. Streptococcus pneumoniae
D. Staphylococcus aureus
Rationale: Streptococcus pneumoniae is the leading cause of
community-acquired pneumonia in adults worldwide due to its
prevalence and pathogenicity. Mycoplasma pneumoniae is more
common in younger patients.
2. A 5-year-old child presents with fever, cough, and a barking cough.
The most likely diagnosis is:
, A. Asthma
B. Croup (laryngotracheobronchitis)
C. Bronchiolitis
D. Epiglottitis
Rationale: Croup typically presents with a barking cough, stridor, and
fever in children aged 6 months to 5 years. Asthma usually presents
with wheezing without stridor.
3. The primary mechanism of action of beta-lactam antibiotics is:
A. Inhibition of protein synthesis
B. Inhibition of bacterial cell wall synthesis
C. Disruption of DNA replication
D. Inhibition of folate synthesis
Rationale: Beta-lactams, such as penicillins and cephalosporins, inhibit
transpeptidase enzymes, preventing cross-linking of peptidoglycan in
bacterial cell walls, leading to lysis.
4. The most appropriate initial test for suspected pulmonary
embolism is:
A. Chest X-ray
B. CT pulmonary angiography
C. D-dimer alone
D. MRI of the chest
,Rationale: CT pulmonary angiography is the gold standard for
diagnosing pulmonary embolism in stable patients, providing direct
visualization of thrombi in pulmonary arteries.
5. A patient with chronic alcoholism presents with confusion, ataxia,
and ophthalmoplegia. The most likely diagnosis is:
A. Hepatic encephalopathy
B. Stroke
C. Wernicke encephalopathy
D. Korsakoff syndrome
Rationale: Wernicke encephalopathy results from thiamine deficiency,
commonly in alcoholics, and presents with the classic triad: confusion,
ataxia, and ophthalmoplegia. Korsakoff syndrome involves chronic
memory impairment.
6. A 30-year-old woman presents with heat intolerance, weight loss,
and palpitations. Laboratory findings reveal low TSH and elevated
T3/T4. The most likely diagnosis is:
A. Hypothyroidism
B. Subclinical hypothyroidism
C. Hyperthyroidism (Graves’ disease likely)
D. Hashimoto thyroiditis
, Rationale: Hyperthyroidism presents with low TSH and high thyroid
hormones. Graves’ disease is the most common cause in adults,
characterized by diffuse goiter and sometimes ophthalmopathy.
7. The most common cause of hypothyroidism worldwide is:
A. Iodine deficiency
B. Hashimoto thyroiditis
C. Pituitary failure
D. Hashimoto thyroiditis
Rationale: In iodine-sufficient countries, Hashimoto thyroiditis is the
leading cause of hypothyroidism, an autoimmune destruction of the
thyroid gland.
8. A 65-year-old man presents with resting tremor, rigidity, and
bradykinesia. The most likely diagnosis is:
A. Essential tremor
B. Huntington disease
C. Parkinson disease
D. Multiple sclerosis
Rationale: Parkinson disease presents with the classic triad of resting
tremor, rigidity, and bradykinesia, typically in older adults.
9. The most appropriate initial therapy for anaphylaxis is:
A. Corticosteroids
