Medicine Special Test-1 Solutions

01.A 56-year-old man is admitted to the hospital for chest pain of 2-hour
duration. His heart rate is 42 bpm, with sinus bradycardia on ECG, as
well as ST-segment elevation in leads II, III, and aVF. Which of the
following is the most likely diagnosis?

A. He is likely in good physical condition with increased vagal tone.
B. He likely has suffered an inferior wall MI.
C. He likely has an LV aneurysm.
D. The low heart rate is a reflection of a good cardiac ejection fraction.

B. Sinus bradycardia is often seen with inferior wall MI, because the
right coronary artery supplies the inferior wall of the left ventricle
and the sinoatrial node. The ischemic changes in leads II, III, and
aVF are in the region of the inferior leads. Understanding which
leads reflect which portion of the heart allows for an understanding
of the aspect of the heart that is affected. Also understanding the
area of the heart perfused by the various coronary arteries allows for
correlation of associated symptoms or therapy.

02.Which of the following is a useful clue to the
diagnosis of Legionella pneumonia?

(A) diarrhea
(B) rash
(C) pedal edema
(D) elevated serum glucose
(E) photophobia

(A) The spectrum of infection with Legionella
organisms ranges from asymptomatic seroconversion
to Pontiac fever (a flu-like illness) to
full-blown pneumonia. Cough is usually nonproductive
initially. Malaise, myalgia, and
headache are common. The diagnosis of
Legionella infection is suggested by extrapulmonary
signs and symptoms, including diarrhea,
abdominal pain, azotemia, and hematuria

03. Which of the following tests is the most important to follow for a
patient receiving isoniazid and rifampin for tuberculosis treatment?
A. Renal function tests
B. Liver function tests
C. Slit-lamp examinations
D. Amylase and lipase tests

B. Drug-induced hepatitis is a common complication of isoniazid
and rifampin and requires periodic surveillance. Alcohol use, prior
liver disease, and increased age are risk factors.


04.A 22-year-old woman is pregnant and at 14-week gestation. Her hemoglobin
level is 9 g/dL. She asks why she could have iron deficiency
when she is no longer menstruating. Which of the following is the best
explanation?
A. Occult gastrointestinal blood loss
B. Expanded blood volume and transport to the fetus
C. Hemolysis
D. Iron losses as a result of relative alkalosis of pregnancy

B. Iron deficiency occurs in pregnancy as a result of the expanded
blood volume and active transport of iron to the fetus.


05.While examining a 46-year-old woman, you hear
a diastolic murmur that is increased when the
patient is in the left lateral decubitus position.
You ask her to run in place for 3 minutes, and the
murmur is found to be accentuated as well by
exercise. What is the most likely valvular defect?
(A) aortic regurgitation
(B) mitral stenosis
(C) tricuspid stenosis
(D) pulmonic regurgitation
(E) VSD

(B) Heart sounds and murmurs can often be
accentuated by various physiologic and pharmacologic
maneuvers. These maneuvers aid in
the differentiation of multiple valvular and
other organic lesions from ordinary sounds.
Mitral stenosis is a diastolic murmur that grows
louder with increased flow across the stenotic
valve, as in exercise. Tricuspid stenosis is heard
best at the lower left sternal border. Aortic
regurgitation is generally reduced by dynamic
exercise due to shortened diastole. AVSD may
be small, and causes a systolic murmur; its
murmur will fade with maneuvers favoring forward
flow, such as vasodilatation with amyl
nitrate. The murmur of aortic stenosis is systolic
and will grow louder with increased flow across
the valve, as with amyl nitrate; it will diminish
with maneuvers that decrease flow across the
valve, as in stage two of the Valsalva maneuver.



06.A 23-year-old man presents complaining of
severe crampy abdominal pain and blood in
his stool over the past 2 days. Asimilar episode
occurred a few months ago and spontaneously
resolved. No history of travel. Abdominal x-ray
shows mild colonic dilatation. Which of the
following is the most likely diagnosis?
(A) ulcerative colitis
(B) viral gastroenteritis
(C) irritable bowel syndrome
(D) celiac sprue
(E) Whipple disease

(A) Ulcerative colitis typically presents between
the ages of 15 and 25 years with symptoms of
diarrhea with blood and abdominal pain.
Involvement begins in the rectum and is limited
to the colon. The recurrent episodes and hematochezia
make inflammatory bowel disease
most likely. (Kasper et al., 2005, pp. 1776–1789)


07.A 36-year-old woman with HIV is admitted with new-onset seizures.
The CT scan of the head reveals multiple ring enhancing lesions of
the brain. Which of the following is the best therapy for the likely
condition?
A. Rifampin, isoniazid, ethambutol
B. Ganciclovir
C. Penicillin
D. Sulfadiazine with pyrimethamine


D. The most common cause of a mass lesion of the brain in an HIV
patient is toxoplasmosis, which is treated with sulfadiazine with
pyrimethamine.



08. A 24-year-old man develops seizures following an emergent splenectomy
after a car accident. His serum sodium level is initially 116 mEq/L
and is corrected to 120 mEq/L over the next 3 hours with hypertonic saline.
Which of the following factors most likely led to his hyponatremia?
A. Elevation of serum vasopressin
B. Administration of hypertonic solutions
C. Volume depletion
D. Seizure-induced hyponatremia

A. In the postoperative state or in situations where the patient is in
pain, the serum vasopressin level may rise, leading to inappropriate
retention of free water, which leads to dilution of the serum.
Concomitant administration of hypotonic fluids may exacerbate the
situation.

09. Which of the following tests is the most important to follow for a
patient receiving isoniazid and rifampin for tuberculosis treatment?
A. Renal function tests
B. Liver function tests
C. Slit-lamp examinations
D. Amylase and lipase tests

B. Drug-induced hepatitis is a common complication of isoniazid
and rifampin and requires periodic surveillance. Alcohol use, prior
liver disease, and increased age are risk factors.



09.Which of the following agents most closely resembles the action of
alcohol in the brain?
A. Amphetamines
B. Marijuana
C. Cocaine
D. Benzodiazepine
E. Acetaminophen

D. Alcohol and benzodiazepines both interact with the ã-aminobutyric
acid (GABA) system; thus, benzodiazepines are the drugs of
choice for treatment of acute alcohol withdrawal.


10.A 57-year-old man is noted to have a blood pressure 68/50 mm Hg,
heart rate 140 bpm, elevated jugular venous pressure, inspiratory
crackles on examination, and cold clammy extremities. Which of the
following is the most likely etiology?
A. Septic shock
B. Adrenal crisis
C. Cardiogenic shock
D. Hypovolemic shock

C. The patient is hypotensive with signs of left- and right-heart failure,
that is, probably cardiogenic shock. Septic shock and adrenal crisis
both are forms of distributive shock that would produce warm
extremities. Hypovolemic shock should have flat neck veins and no
pulmonary edema.

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