STEP 1 FIRST AID RAPID REVIEW QUESTIONS AND ANSWERS
200 COMPREHENSIVE QUESTIONS COMPLETE WITH 100%
VERIFIED ANSWERS
1. A 45-year-old woman presents with fatigue, weight gain, cold
intolerance, and constipation. Laboratory studies show elevated TSH
and low free T4. What is the most likely diagnosis?
A) Graves disease
B) Hashimoto thyroiditis
C) Subacute thyroiditis
D) Pituitary adenoma
Answer: B) Hashimoto thyroiditis
Rationale: Primary hypothyroidism is most commonly caused by
Hashimoto thyroiditis, an autoimmune destruction of the thyroid gland.
Elevated TSH with low free T4 indicates primary hypothyroidism, with
Hashimoto being the most frequent etiology in iodine-sufficient areas.
Antithyroid peroxidase antibodies are typically present.
2. Which medication is the first-line treatment for stable angina?
A) Nitroglycerin
B) Atenolol
C) Amlodipine
D) Aspirin
,Answer: B) Atenolol
Rationale: Beta-blockers are first-line therapy for stable angina as they
reduce myocardial oxygen demand by decreasing heart rate,
contractility, and blood pressure. They improve exercise tolerance and
reduce the frequency of anginal episodes. Nitroglycerin is used for
acute relief, while calcium channel blockers are alternatives.
3. A 60-year-old man with a history of hypertension presents with
sudden onset severe headache, nausea, and photophobia. CT scan
shows subarachnoid hemorrhage. What is the most common cause?
A) Arteriovenous malformation
B) Ruptured berry aneurysm
C) Hypertension
D) Trauma
Answer: B) Ruptured berry aneurysm
Rationale: Ruptured berry (saccular) aneurysms are the most common
cause of subarachnoid hemorrhage, accounting for approximately 85%
of cases. They typically occur at bifurcation points in the circle of Willis.
The most common location is the anterior communicating artery.
4. What organism is the most common cause of community-acquired
pneumonia in young adults?
A) Streptococcus pneumoniae
B) Mycoplasma pneumoniae
C) Chlamydophila pneumoniae
D) Haemophilus influenzae
,Answer: B) Mycoplasma pneumoniae
Rationale: In young adults (18-40 years), Mycoplasma pneumoniae is
the most common cause of atypical community-acquired pneumonia. It
presents with gradual onset, dry cough, and extrapulmonary
manifestations. Streptococcus pneumoniae remains most common
overall, but Mycoplasma predominates in this specific age group.
5. A 25-year-old woman presents with episodic palpitations, sweating,
and hypertension. Laboratory studies reveal elevated plasma
metanephrines. What is the most likely diagnosis?
A) Cushing syndrome
B) Pheochromocytoma
C) Hyperthyroidism
D) Carcinoid syndrome
Answer: B) Pheochromocytoma
Rationale: Pheochromocytoma is a catecholamine-secreting tumor of
the adrenal medulla that presents with episodic hypertension,
palpitations, diaphoresis, and headache. Elevated plasma
metanephrines is the most sensitive screening test. The "rule of 10s"
applies: 10% bilateral, 10% malignant, 10% extra-adrenal, 10% familial.
6. Which cardiac biomarker is most specific for acute myocardial
infarction?
A) CK-MB
B) Troponin I
, C) Myoglobin
D) LDH
Answer: B) Troponin I
Rationale: Troponin I and T are highly specific for cardiac muscle injury
and are the preferred biomarkers for diagnosing acute MI. They begin
to rise 3-4 hours after symptom onset and remain elevated for 7-10
days. Unlike CK-MB, they are not elevated in skeletal muscle injury.
7. A 55-year-old man with chronic alcoholism presents with confusion,
ataxia, and ophthalmoplegia. What vitamin deficiency is most likely
responsible?
A) Vitamin B1 (Thiamine)
B) Vitamin B3 (Niacin)
C) Vitamin B12
D) Vitamin B6
Answer: A) Vitamin B1 (Thiamine)
Rationale: Wernicke encephalopathy presents with the classic triad of
confusion, ataxia, and ophthalmoplegia. It is caused by thiamine
deficiency, most commonly seen in chronic alcoholics, but also occurs in
malnourished states. Immediate IV thiamine administration is required
to prevent progression to Korsakoff syndrome.
8. What electrolyte disturbance is most commonly associated with
digitalis toxicity?
200 COMPREHENSIVE QUESTIONS COMPLETE WITH 100%
VERIFIED ANSWERS
1. A 45-year-old woman presents with fatigue, weight gain, cold
intolerance, and constipation. Laboratory studies show elevated TSH
and low free T4. What is the most likely diagnosis?
A) Graves disease
B) Hashimoto thyroiditis
C) Subacute thyroiditis
D) Pituitary adenoma
Answer: B) Hashimoto thyroiditis
Rationale: Primary hypothyroidism is most commonly caused by
Hashimoto thyroiditis, an autoimmune destruction of the thyroid gland.
Elevated TSH with low free T4 indicates primary hypothyroidism, with
Hashimoto being the most frequent etiology in iodine-sufficient areas.
Antithyroid peroxidase antibodies are typically present.
2. Which medication is the first-line treatment for stable angina?
A) Nitroglycerin
B) Atenolol
C) Amlodipine
D) Aspirin
,Answer: B) Atenolol
Rationale: Beta-blockers are first-line therapy for stable angina as they
reduce myocardial oxygen demand by decreasing heart rate,
contractility, and blood pressure. They improve exercise tolerance and
reduce the frequency of anginal episodes. Nitroglycerin is used for
acute relief, while calcium channel blockers are alternatives.
3. A 60-year-old man with a history of hypertension presents with
sudden onset severe headache, nausea, and photophobia. CT scan
shows subarachnoid hemorrhage. What is the most common cause?
A) Arteriovenous malformation
B) Ruptured berry aneurysm
C) Hypertension
D) Trauma
Answer: B) Ruptured berry aneurysm
Rationale: Ruptured berry (saccular) aneurysms are the most common
cause of subarachnoid hemorrhage, accounting for approximately 85%
of cases. They typically occur at bifurcation points in the circle of Willis.
The most common location is the anterior communicating artery.
4. What organism is the most common cause of community-acquired
pneumonia in young adults?
A) Streptococcus pneumoniae
B) Mycoplasma pneumoniae
C) Chlamydophila pneumoniae
D) Haemophilus influenzae
,Answer: B) Mycoplasma pneumoniae
Rationale: In young adults (18-40 years), Mycoplasma pneumoniae is
the most common cause of atypical community-acquired pneumonia. It
presents with gradual onset, dry cough, and extrapulmonary
manifestations. Streptococcus pneumoniae remains most common
overall, but Mycoplasma predominates in this specific age group.
5. A 25-year-old woman presents with episodic palpitations, sweating,
and hypertension. Laboratory studies reveal elevated plasma
metanephrines. What is the most likely diagnosis?
A) Cushing syndrome
B) Pheochromocytoma
C) Hyperthyroidism
D) Carcinoid syndrome
Answer: B) Pheochromocytoma
Rationale: Pheochromocytoma is a catecholamine-secreting tumor of
the adrenal medulla that presents with episodic hypertension,
palpitations, diaphoresis, and headache. Elevated plasma
metanephrines is the most sensitive screening test. The "rule of 10s"
applies: 10% bilateral, 10% malignant, 10% extra-adrenal, 10% familial.
6. Which cardiac biomarker is most specific for acute myocardial
infarction?
A) CK-MB
B) Troponin I
, C) Myoglobin
D) LDH
Answer: B) Troponin I
Rationale: Troponin I and T are highly specific for cardiac muscle injury
and are the preferred biomarkers for diagnosing acute MI. They begin
to rise 3-4 hours after symptom onset and remain elevated for 7-10
days. Unlike CK-MB, they are not elevated in skeletal muscle injury.
7. A 55-year-old man with chronic alcoholism presents with confusion,
ataxia, and ophthalmoplegia. What vitamin deficiency is most likely
responsible?
A) Vitamin B1 (Thiamine)
B) Vitamin B3 (Niacin)
C) Vitamin B12
D) Vitamin B6
Answer: A) Vitamin B1 (Thiamine)
Rationale: Wernicke encephalopathy presents with the classic triad of
confusion, ataxia, and ophthalmoplegia. It is caused by thiamine
deficiency, most commonly seen in chronic alcoholics, but also occurs in
malnourished states. Immediate IV thiamine administration is required
to prevent progression to Korsakoff syndrome.
8. What electrolyte disturbance is most commonly associated with
digitalis toxicity?
