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Posted by baba from IP 24.34.79.246 on August 06, 2014 at 04:18:59:

A previously healthy, 22-year-old woman comes to
medical attention because of mild jaundice, low-grade
fever, arthralgia, malaise, and amenorrhea for 3
months. She does not drink alcohol or smoke. She
does not take any medications other than oral
contraceptives. Serum chemistry studies show
elevated AST and ALT levels,
hypergammaglobulinemia, and high titers of
circulating antinuclear and anti-smooth muscle
autoantibodies. Serologic studies of antibodies to
hepatitis viruses are as follows:

HAV
Negative
HBV
Negative
HCV
Positive, by enzyme immunoassay
HCV
Negative, by recombinant immunoblot assay
(RIBA)


A liver biopsy demonstrates lymphocytic portal
inflammation with early bridging necrosis. Which of
the following is the most likely diagnosis?


A. Autoimmune hepatitis

B. Chronic hepatitis C

C. Hepatic adenoma

D. Nonalcoholic steatohepatitis

E. Primary biliary cirrhosis


Explanation:

The correct answer is A. Clinical symptomatology
and laboratory findings are consistent with chronic
"autoimmune" hepatitis (AH). The biopsy findings
support this diagnosis, demonstrating portal
inflammation with lobular damage resulting in
bridging necrosis. The young age of the patient and
presence of hypergammaglobulinemia are also
common in this condition. There are two major types
of AH. Type I, or the classic type, is the most
frequent; it is associated with antinuclear and
anti-smooth muscle autoantibodies. Type II, which is
more common in women of Western European
descent, is associated with autoantibodies to
circulating liver-kidney microsomes. The onset is
usually insidious, and a history of amenorrhea is
frequently present.

Chronic hepatitis C (choice B) develops in 80% of
cases of hepatitis C virus infection. It may manifest
years after the often-asymptomatic acute infection
with signs and symptoms of chronic hepatitis or liver
failure. The diagnosis is confirmed by positive
enzyme immunoassay test for HCV-antibodies.
However, this test may be falsely positive in
situations with hypergammaglobulinemia. In such
cases, positivity should be confirmed by a more
specific RIBA. In this case, RIBA was negative, ruling
out hepatitis C.

Hepatic adenoma (choice C) is a benign
hepatocellular neoplasm associated with use of oral
contraceptives or anabolic androgens. It is usually
clinically silent but may occasionally manifest with
life-threatening peritoneal bleeding.

Nonalcoholic steatohepatitis (choice D) mimics
alcoholic hepatitis both clinically and
histopathologically. It is characterized by fatty
change of the liver with associated laboratory signs
of hepatocellular injury. Obesity and diabetes are
the most common predisposing conditions.

Primary biliary cirrhosis (choice E) has a
predilection for middle-aged women. It manifests
with progressive signs of cholestasis, in which
pruritus and xanthomas are often the earliest signs.
Antimitochondrial autoantibodies are found in 90% to
95% of these patients.


A 3-week-old boy presents to the physician's office
with a 1-week history of forceful, projectile vomiting.
He has been vomiting after almost every feeding.
The vomitus contains mostly undigested formula and
is non-bilious. On examination, his oral mucosa is
dry, his anterior fontanel appears to be depressed,
and his capillary refill is 3-4 seconds. An abdominal
examination reveals an olive-sized mass in the
epigastrium. Which of the following electrolyte
findings will most likely be seen?


A. Hypochloremic metabolic acidosis

B. Hypochloremic metabolic alkalosis

C. Normal electrolytes

D. Respiratory acidosis with metabolic
compensation

E. Respiratory alkalosis


Explanation:

The correct answer is B. This baby most likely
has pyloric stenosis. Pyloric stenosis occurs in
approximately 1:500 births. Male infants are more
commonly affected than female infants are, and the
incidence is far greater in full-term infants than in
preterm infants. Clinical manifestations include
projectile non-bilious vomiting shortly after feeding
and an olive-sized mass palpable in the
epigastrium. Symptoms typically present in the 2nd
or 3rd week of life. As the vomiting continues,
hydrogen ions and chloride ions begin to decrease
in the body, causing hypochloremic metabolic
alkalosis. In addition, the infant might also be
hypokalemic from repeated vomiting. Plain
radiographs may demonstrate the absence of air
distal to the obstructed pylorus. In barium contrast
studies, a small amount of barium may pass through
the hypertrophied pylorus, causing the "string sign."
Ultrasound studies are also useful in demonstrating
the hypertrophied pylorus. The dehydration and
electrolyte abnormalities should be corrected.
Definite treatment is pyloromyotomy.


A 4th-year medical student is performing a mental
status examination on a 78-year-old man with a
history of Alzheimer disease and recent cognitive
decline. She asks the patient what he would do if he
found someone else's social security check mixed in
with his own mail at home. Which of the following is
the student testing in the mental status examination
by asking this question?


A. Abstract thinking

B. Cognition

C. Insight

D. Intelligence

E. Judgment


Explanation:

The correct answer is E. Judgment is the ability
of a patient to evaluate a particular course of
action in order to determine if it is the most
appropriate one within the patient's particular value
system. If the patient were to say he would put the
letter back in the mail or give it back to the
postman, this would indicate appropriate judgment.

Abstract thinking (choice A) is the ability to think
or perform symbolically, or to evaluate various
aspects of a situation and shift between
alternatives.

Cognition (choice B) is tested by evaluating the
intellectual and perceptual levels of mental
functioning.

Insight (choice C) is the ability to recognize the
objective reality of a situation.

Intelligence (choice D) is the ability to learn and
apply learned information to a given situation.


A 12-year-old female comes to the physician
because of a vaginal discharge. The discharge
started about 2 months ago and is whitish in color.
There is no odor. The patient has no complaints of
itching, burning, or pain. The patient started breast
development at 9 years of age and her pubertal
development has proceeded normally to this point.
She has not had her first menses and she is not
sexually active. She has no medical problems.
Examination is normal for a 12-year-old female.
Microscopic examination of the discharge shows no
evidence of pseudohyphae, clue cells, or
trichomonads. Which of the following is the most
likely diagnosis?


A. Bacterial vaginosis

B. Candida vulvovaginitis

C. Physiologic leukorrhea

D. Syphilis

E. Trichomoniasis


Explanation:

The correct answer is C. Physiologic leukorrhea
can be seen during 2 different periods of childhood.
Some female neonates develop a physiologic
leukorrhea shortly after birth as maternal circulating
estrogens stimulate the newborn's endocervical
glands and vaginal epithelium. The discharge in
these neonates is often gray and gelatinous.
Physiologic leukorrhea can also be seen during the
months preceding menarche. During this time, rising
estrogen levels lead to a whitish discharge not
associated with any symptoms of irritation. This
patient has a whitish discharge, no other symptoms,
and she has had normal pubertal development up to
this point. The discharge itself has no
characteristics of infection. Therefore, physiologic
leukorrhea is the most likely diagnosis.

Bacterial vaginosis (choice A) is not the most likely
diagnosis in this patient because the discharge is
not malodorous and there are no clue cells seen on
microscopic examination of the discharge.

Candida vulvovaginitis (choice B) is not the most
likely diagnosis because the discharge is not thick
and white (or "cottage-cheese"-like) and the patient
has no irritative symptomatology.

Syphilis (choice D) most often presents with a
painless ulcer (called a chancre) or is found with
serologic testing. A nonmalodorous, whitish vaginal
discharge in a 12-year-old female who is not
sexually active is almost certainly not evidence of
syphilis.

Trichomoniasis (choice E) is also highly unlikely in
this patient and the lack of trichomonads on the
microscopic examination effectively rules out this
diagnosis.


A 49-year-old woman has a firm, 2-cm mass in the
right breast that has been present for 3 months.
Mammogram has been read as "cannot rule out
cancer," but it cannot diagnose cancer either. A
fine-needle aspiration of the mass (FNA) and
cytology do not identify any malignant cells. Which
of the following is the most appropriate next step in
management?


A. Reassurance and reappointment in a year

B. Repeat mammogram and FNA in 1 month

C. Core or incisional biopsies

D. Lumpectomy and axillary dissection

E. Modified radical mastectomy


Explanation:

The correct answer is C. Negative findings do
not have the same diagnostic value that positive
findings have. If this had been a 19-year-old
woman suspected of having a fibroadenoma, one
would have been satisfied with negative imaging
studies (in that age, a sonogram) or the negative
FNA. But, at age 49, the risk of cancer is much
higher. Given negative findings in the least invasive
studies, one would feel compelled to move to more
aggressive ways to obtain better tissue sampling.

Obviously, reassurance (choice A) is not justified
yet, and waiting a whole year with what may be a
cancer would be malpractice.

Repeating the same studies in a month (choice B)
leaves you with the quandary of what to do if they
are negative again. No, you need more tissue for
the pathologist right now.

Lumpectomy and axillary dissection (choice D) is
too much to do before the diagnosis has been
established. Lumpectomy alone might have been
okay. An excisional biopsy could indeed be justified
under the circumstances, and a lumpectomy is not
much more than a big excisional biopsy. But,
messing with the axilla should not happen before
we know it is cancer.

Mastectomy (choice E) is even less acceptable.
Patients are grateful when a cancer is ruled out by
procedures that they do not perceive as mutilating.
But, when surgery leaves them deformed, the
"good news" that there was no cancer may lead
them to call their lawyer.


A vomiting infant is brought to the emergency room.
The blood work results reveal a normal blood count,
but a hyponatremic, hypochloremic, metabolic
alkalosis. Which of the following would be consistent
with these findings?


A. Diabetes mellitus

B. Cystic fibrosis

C. Ethanol poisoning

D. Iron ingestion

E. Isoniazid ingestion


Explanation:

The correct answer is B. Although metabolic
alkalosis is an uncommon presentation for cystic
fibrosis, it is the correct answer. Particularly in the
summer time with excess sweating, infants with
cystic fibrosis may present with dehydration and
this electrolyte pattern.

Although diabetes (choice A) might present with a
low serum sodium, it is associated with
ketoacidosis, not alkalosis.

Ethanol poisoning (choice C) poses particular
problems with hypoglycemia, respiratory
depression, and metabolic acidosis.

Acute iron poisoning (choice D) may result in
metabolic acidosis, not alkalosis. Fever and
leukocytosis may be present and coma may ensue.
Also, acute iron ingestion may present with
hemorrhagic gastroenteritis.

Isoniazid ingestion (choice E) is associated with
metabolic acidosis and an elevated anion gap.


A 34-year-old perfume saleswoman presents
complaining of lower abdominal cramps and diarrhea.
She has no prior history of gastrointestinal illnesses
and began noting frequent loose stools 3 days
earlier. The stools have subsequently become bloody
and associated with urgency and nocturnal bowel
movements. She has also developed an increased
temperature of 38.4 C (101.1 F). On examination, she
has mild periumbilical and left lower quadrant
tenderness. On rectal examination, the stool is
bloody. Which of the following organisms is most
likely causing her symptoms?


A. Campylobacter jejuni

B. Cryptosporidium

C. Giardia lamblia

D. Staphylococcus aureus

E. Toxigenic Escherichia coli


Explanation:

The correct answer is A.Campylobacter jejuni is a
common cause of community-acquired bloody
diarrhea. It is acquired via the fecal-oral route and
may produce a non-bloody or bloody diarrhea. If the
symptoms are as severe as in this patient,
antibiotics (e.g., ciprofloxacin) would be appropriate.

Cryptosporidium(choice B) is a parasite that can
infect immunocompetent individuals and will produce
a self-limited watery diarrhea. When it infects AIDS
patients it typically leads to a chronic, watery
diarrheal syndrome that produces severe weight
loss.

Giardia lamblia(choice C) also causes an upper
gastrointestinal infection but presents with upper
abdominal symptoms and a non-bloody diarrhea.

Staphylococcus aureus(choice D) causes a
food-borne infection that will produce upper
abdominal pain and nausea and vomiting,
secondary to a preformed ingested toxin. The
characteristic feature of this infection is its prompt
occurrence, i.e., within approximately 4-8 hours of
the ingestion of the tainted food.

Toxigenic Escherichia coli(choice E) presents with
a watery diarrhea, acquired through the fecal-oral
route as a traveler's diarrhea.


A 43-year-old African American woman comes to the
physician because of her concern regarding breast
cancer. She has no complaints at present. In past
years, she had noted bilateral breast tenderness
prior to her menses, but this has since abated. She
has no medical problems. She had two cesarean
deliveries, but no other surgeries. She takes a
low-dose oral contraceptive pill and has no known
drug allergies. She does not smoke, and her family
history is negative. Physical examination is normal.
All mammograms (yearly since age 40) have been
negative to date. She wants to know whether BRCA1
and BRCA2 screening would be appropriate for her.
Which of the following is the correct response?


A. BRCA1 and 2 screening is not
recommended

B. BRCA1 and 2 screening should be
performed after age 50

C. BRCA1 and 2 screening should be
performed if breast pain recurs

D. BRCA1 screening is recommended

E. BRCA2 screening is recommended


Explanation:

The correct answer is A. Of the cases of breast
cancer that are heritable, approximately 80% are
due to mutations in BRCA1 and BRCA2. BRCA1 is
associated with high risk for breast and ovarian
cancer. BRCA2 is associated with a high risk of
female and male breast cancer. On the basis of our
current understanding, however, less than 10% of
all breast cancer cases can be considered to be
heritable. Therefore, the total number of breast
cancer cases associated with BRCA1 and BRCA2
mutations is a small percentage of the total number
of breast cancer cases. Furthermore, there are
numerous mutations that can occur in the BRCA1
and BRCA2 genes and can be related to an
increased cancer risk. Some patients who have a
mutation associated with cancer will not go on to
develop cancer. Other patients may have a strong
family history of breast cancer but no identifiable
mutation. At present, therefore, screening of the
general population is not recommended. This
patient has no family history and is not in a high-risk
group. Her prior breast tenderness was likely
mastalgia related to the premenstrual phase.
Therefore, BRCA1 and 2 screening would not be
recommended for this patient.

To state that BRCA1 and 2 screening should be
performed after age 50 (choice B) is incorrect. As
noted above, given the limitations of the testing for
BRCA1 and 2 mutations, screening of the general
population is not recommended.

To state that BRCA1 and 2 screening should be
performed if breast pain recurs (choice C) is
incorrect. This patient does not need screening, not
because her breast pain has resolved, but rather
because BRCA1 and 2 screening is not appropriate
for the general population at this time. As noted
above, her breast pain was likely cyclic mastalgia
secondary to hormonal changes prior to menses.

To state that either BRCA1 screening (choice D) or
BRCA2 screening (choice E) is recommended is
not correct. As explained above, screening for
neither of these is recommended.


A 23-year-old African American man with AIDS is
sent for work up of the nephrotic syndrome. His
blood pressure is 140/82 mm Hg. He has 3+ edema
in both legs. His risk factor for AIDS is IV heroin use.
His creatinine is 2.0 mg/dL, and his urine reveals +3
protein, no blood. A kidney biopsy would most likely
reveal which of the following?


A. Diabetic nephropathy

B. Focal glomerular sclerosis

C. IgA nephropathy

D. Membranous nephropathy

E. Nil disease


Explanation:

The correct answer is B. Focal glomerular
sclerosis is the type of nephropathy most
commonly seen in African American IV drug users
with AIDS. It is likely to lead to a very rapid loss of
renal function.

There is no clinical evidence to indicate that this
person has diabetes, making diabetic nephropathy
(choice A) unlikely.

Nil disease (choice E), IgA nephropathy (choice
C) and membranous nephropathy (choice D) are
only very rarely associated with AIDS.


A 70-year-old woman with long history of diabetes
mellitus presents with sudden onset of weakness in
the right arm. Physical examination confirms loss of
strength in the right upper extremity and further
demonstrates subtle bilateral neurologic deficits,
both sensory and motor. A CT scan of the head
shows small punched-out hypodense areas in the
basal ganglia and anterior limb of the left internal
capsule. Which of the following is the most likely
diagnosis?


A. Berry aneurysms

B. Cerebral hemorrhage

C. Embolic infarcts

D. Lacunar infarcts

E. Metastatic lesions


Explanation:

The correct answer is D. Lacunar infarcts are
small (less than 0.5 cm) focal areas of parenchymal
loss found in the basal ganglia, anterior limb of the
internal capsule, pons, and occasionally cerebral
white matter. They are presumed to be of ischemic
origin, but their pathogenetic mechanism has not
yet been elucidated. It is a fact that lacunae are
particularly frequent in persons suffering from
hypertension or diabetes mellitus, both conditions
being associated with systemic arteriolosclerosis.
Arteriolosclerosis leads to ischemic damage to
several organs, particularly the brain and kidneys.
Lacunar infarcts manifest with focal neurologic
deficits that tend to recover spontaneously.

Berry aneurysms (choice A) are either
asymptomatic or manifest with sudden
subarachnoid bleeding. Only rarely do they
manifest by compression of cranial nerves.
Aneurysms of the circle of Willis are not visible on
regular CT scans.

Cerebral hemorrhage (choice B) is identified on
CT scans as intraparenchymal hyperdense areas.
Hypertension is the most common predisposing
condition. The patient usually presents with sudden
onset of headache and rapid deterioration of
mental status.

Embolic infarcts (choice C) are most commonly
hemorrhagic in origin. They usually involve the
cerebral cortex in a wedge-shaped distribution.

Metastatic lesions (choice E) manifest as sharply
demarcated nodules usually located at the junction
between gray and white matter


After a minor but distressing automobile accident, a
patient is unable to move one leg. Careful physical
examination demonstrates no obvious injury that
might have caused the paralysis. His reflexes are
intact. A CT of the spine demonstrates no back
injury. The patient is reassured, and the paralysis
resolves over a 2-week period. Which of the
following is the most likely diagnosis?


A. Body dysmorphic disorder

B. Conversion disorder

C. Munchausen syndrome

D. Pain disorder

E. Somatization disorder


Explanation:

The correct answer is B. This case illustrates
conversion disorder. In this condition, physical
symptoms are caused by psychological conflict.
The symptoms develop unconsciously and are, by
definition, limited to those that mimic a neurologic
disorder, such as impaired coordination, weakness,
paralysis, loss of sensation, blindness, deafness,
or inability to speak. The onset is usually abrupt
and linked to a stressful event. In most patients,
symptoms improve within 2 weeks, although some
patients will have persistent or recurrent problems.

Body dysmorphic disorder (choice A) refers to an
abnormal body image, such as when a youthful
patient believes she is terribly wrinkled even when
everyone around her perceives her as young.

Patients with Munchausen syndrome (choice C)
tend to have elaborate and deliberate fabrications
of illness that don't usually resolve spontaneously.

Pain disorder (choice D) is the term used for
patients with persistent problems of psychogenic
pain.

Somatization disorder (choice E) usually involves
long-standing, nonspecific bodily complaints.


A 40-year-old woman has an 8-month history of
diffuse joint pain and swelling that involves both
hands and knees. She states that she cannot get any
work done in the morning due to the pain, but it
usually subsides as the day progresses. She tires
easily and constantly feels "feverish". Her
temperature is 37.8 C (100 F), blood pressure is
110/70 mm Hg, pulse is 60/min, and respirations are
18/min. Physical examination shows tender, swollen,
and "boggy" hands and knees. Laboratory studies
show:

Hematocrit............34%

Hemoglobin...........10 g/dLA radiograph of this
patient's knee is most likely to show which of the
following?


A. Bone erosions

B. Osteophyte formation

C. Subchondral cyst formation

D. Subchondral sclerosis

E. Subchondral tophi


Explanation:

The correct answer is A. This patient most likely
has rheumatoid arthritis, a chronic inflammatory
disorder characterized by symmetrical joint
involvement and extraarticular manifestations. It
typically affects middle-aged women. Symptoms
include joint pain and swelling, low-grade fever,
malaise, fatigue, vasculitis, pericarditis, rheumatic
nodules, episcleritis, and scleritis. Laboratory
findings include normochromic, normocytic anemia,
increased erythrocyte sedimentation rate, and
serum rheumatoid factors. The proximal
interphalangeal joints (PIP), metacarpophalangeal
joints (MCP), and the wrist joints are the most
commonly involved joints. Distal interphalangeal
joints (DIP) are usually spared. Radiographic
findings include soft tissue swelling, joint effusions,
juxtaarticular osteopenia, loss of articular cartilage,
joint space narrowing, and bone erosions. The
treatment includes rest, physical therapy, NSAIDs,
aspirin, corticosteroids, gold, methotrexate,
penicillamine, cyclosporine, sulfasalazine, and
hydroxychloroquine.

Osteophyte formation (choice B), subchondral cyst
formation (choice C), and subchondral sclerosis
(choice D) are the radiographic findings of
osteoarthritis. Osteoarthritis is a noninflammatory
joint disease characterized by loss of articular
cartilage and the aforementioned findings. The
symptoms include a deep, aching joint pain that is
aggravated by use and relieved by rest. Physical
examination shows joint tenderness, bony crepitus,
warmth and deformities (Heberden's nodes-DIP and
Bouchard's nodes-PIP). Age, wear and tear,
obesity, trauma, and certain chronic conditions are
factors that increase the risk of osteoarthritis. The
treatment includes weight loss, physical therapy,
acetaminophen, and surgery.

Subchondral tophi (choice E) are found in gouty
arthritis. They typically appear as "punched out"
lesions of the subchondral bone. A tophus is a
collection of urate crystals, inflammatory cells, and
fibrosis. Tophi can lead to cartilage and bone
destruction.


A 39-year-old automobile mechanic presents
because of the new onset of wheezing. He is
otherwise healthy and runs approximately 3 miles per
day. He denies any nocturnal wheezing or cough. He
has a history of chronic heartburn, for which he takes
ranitidine nightly. He also has a history of
hypertension, which has been difficult to control, and
over the past several months he has been taking a
combination of propranolol, enalapril, and
hydrochlorothiazide. His only other medication is
occasional pseudoephedrine for symptoms of allergic
rhinitis. On physical examination, he appears
comfortable. His blood pressure is 134/88 mm Hg,
pulse is 68/min, and respirations are 18/min. On lung
examination, soft expiratory wheezes are heard
throughout both lung fields. Which of the following
medications is most likely contributing to his
wheezing?


A. Enalapril

B. Hydrochlorothiazide

C. Propranolol

D. Pseudoephedrine

E. Ranitidine


Explanation:

The correct answer is C. Propranolol, like other
nonspecific beta blockers, may cause
bronchospasm by blocking the beta receptors in the
bronchial tree. Beta stimulation in the lungs
produces bronchodilation, and its blockade leads to
bronchoconstriction. In fact, propranolol is
contraindicated in patients with known asthma or
chronic obstructive pulmonary disease (COPD).

Enalapril (choice A) may cause pulmonary
symptoms, in that it may cause a nonproductive
cough, but is not usually associated with wheezing.

Hydrochlorothiazide (choice B) and ranitidine
(choice E) have no effect on airway
responsiveness, although the patient's underlying
gastroesophageal refl

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