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In the 25th week of pregnancy, a G1P0 woman develops increased blood pressure (160/95) and proteinuria.
Physical examination demonstrates generalized edema, and serum chemistries demonstrate hyperuricemia and
increased concentrations of liver enzymes. Which of the following usually provides definitive therapy for this
patient's medical condition
A. Anti-hypertensive medical therapy
B. Delivery
C. Low dose aspirin
D. Oxygen supplementation
E. Renal dialysis
Explanation:
The correct answer is B. The woman has preeclampsia, the features of which include proteinuria and increased
blood pressure. A wide variety of other features of preeclampsia can also be seen, including excessive weight
gain, generalized edema, ascites, hyperuricemia, hypocalciuria, increased plasma concentration of von
Willebrand factor and cellular fibronectin, reduced plasma concentration of anti-thrombin III, thrombocytopenia,
increased hematocrit, increased liver enzymes, intrauterine growth retardation, and intrauterine hypoxia.
Modern theories suggest that the true primary lesion may involve the endothelium, and that medical control of
hypertension (choice A) actually only treats a small part of the syndrome. At present, the only definitive therapy
is delivery of the baby, and obstetricians often play a delicate game trying to delay delivery for a premature
baby's sake as long as possible while judging the severity of the preeclampsia and its immediate risks to mother
and fetus.
Low dose aspirin (choice C) may have a modest effect in preventing pre-eclampsia, but this is not yet well
established.
Oxygen supplementation (choice D) is used in some cases of cerebral hemorrhage secondary to preeclampsia,
but does not constitute definitive therapy.
Renal dialysis (choice E) is usually not necessary in preeclampsia, although both renal cortical necrosis and
renal tubular necrosis can occasionally occur in this disorder.
A baby is born with a large red, raised discoloration of the face that persists into adulthood. This type of lesion ismost likely a component of which of the following syndromes?
A. Arnold Chiari malformation
B. Dandy-Walker malformation
C. Neurofibromatosis
D. Sturge-Weber disease
E. Tuberous sclerosis
Explanation: The correct answer is D. The lesion is a port wine stain, which is a vascular lesion that, unlike the more common strawberry nevus, does not usually regress with age. These lesions can be a component of Sturge-Weber disease, which can also include similar vascular lesions of the meninges (leptomeningeal angiomatosis) and sometimes cutaneous angiomatosis at other sites.
Arnold Chiari malformations (choice A) are a cluster of related brain and spinal cord malformations in which
there is a downward displacement of the cerebellar vermis and tonsils into the foramen magnum.
Dandy-Walker malformation (choice B) includes a distended fourth ventricle with a hypoplastic (or absent) cerebellum.
Neurofibromatosis (choice C) includes benign and malignant peripheral nerve lesions and café au lait spots.
Tuberous sclerosis (choice E) includes cortical tubers, adenoma sebaceum of the skin, pancreatic cysts, renal angiomyolipomas, and cardiac rhabdomyomas.
Renal biopsy demonstrates concentric, laminated thickening of arteriolar walls due to proliferation of smooth muscle cells. This process is best described by which of the following terms?
A. Atherosclerosis
B. Hyaline arteriolosclerosis
C. Hyperplastic arteriolosclerosis
D. Mönckeberg's arteriosclerosis
E. Polyarteritis nodosa
Explanation:
The correct answer is C. The "onion skinning" morphology of these arterioles is a feature of hyperplastic
arteriolosclerosis. Affected vessels may also show necrotizing arteriolitis with acute vessel wall necrosis
accompanied by fibrin deposition. This type of vessel change is a hallmark of severe (malignant) hypertension,
and can damage arterioles throughout the body, notably in the kidneys, intestine, and gall bladder.
Atherosclerosis (choice A) would produce luminal narrowing by plaques.
Hyaline arteriolosclerosis (choice B) would produce partial replacement of arterial walls by homogeneous, pink
material.
Mönckeberg's arteriosclerosis (choice D) is characterized by medial calcification of smaller arteries.
Polyarteritis nodosa (choice E) is characterized by focal acute inflammation of smaller arteries.
Two bone marrow aspirates are studied under the microscope. One is taken from an adult with Hemoglobin SS disease (sickle cell anemia) and the other is from an adult with normal Hemoglobin A. The marrow aspirate from the patient with sickle cell anemia could be identified due to its increased
A. fat
B. iron stores
C. medullary bone
D. megakaryocytes
E. myeloid:erythroid ratio
Explanation:
The correct answer is B. Adults with sickle cell disease have undergone decades of accelerated RBC formation and destruction, leading to accelerated erythropoiesis in the bone marrow. Consequently the bone marrow becomes hyperplastic, with marked increases in the number of normoblasts (erythroblasts) at the expense of
marrow fat and marrow bone (choices A and C). Although the white cell and megakaryocyte lines are
undiminished (choices D and E), there is a marked increase in RBC precursors and iron stores. Iron storage
increases as a consequence of both chronic transfusions and increased dietary absorption; these increased
iron stores can be appreciated with a Prussian blue stain.
Ultrasound examination of a developing fetus demonstrates a fluid-filled sac at the base of the fetus' spine that connects to the spinal canal and apparently contains part of the spinal cord. A dietary deficiency of which of the following is most strongly associated with this type of lesion?
A. Calcium
B. Folate
C. Iron
D. Vitamin C
E. Vitamin K
Explanation:
The correct answer is B. The lesion is a neural tube defect, probably a meningomyelocele, in which both
meninges and spinal cord herniate through a bony vertebral defect. These defects most commonly occur in the
lumbosacral region, typically resulting in motor and sensory deficits in the lower extremities, and bowel and
bladder dysfunction. This condition is now known to be associated with low maternal folate during the first three
to four weeks of pregnancy, a time when many women may be unaware of their pregnancy. It is now
recommended that all women of childbearing age consume at least 400 µg of folic acid daily.
Calcium deficiency (choice A) can cause osteoporosis and osteopenia.
Iron deficiency (choice C) can cause iron deficiency anemia.
Vitamin C deficiency (choice D) can cause scurvy.
Vitamin K deficiency (choice E) can cause a bleeding diathesis.
A 30-year-old patient presents to a clinician because of intermittent, severe headaches accompanied by
perspiration, palpitations, and pallor. Blood pressure on the initial examination was within normal limits, but, when the patient came in later with a headache, it was 180/135 mm Hg. Urinary vanillylmandelic acid (VMA) levels were elevated. Roughly, what percentage of the tumors causing this pattern is malignant?
A. 1%
B. 10%
C. 50%
D. 90%
E. 99%
Explanation:
The correct answer is B. The tumor is a pheochromocytoma that intermittently secretes epinephrine and other vasoactive amines, producing episodes of elevated blood pressure accompanied by headache. This is the tumor to associate with the rule of the 10's: 10% malignant, 10% bilateral, 10% extra-adrenal, 10% calcify, 10% occur in kids, and 10% are familial. It is also a favorite target on examinations, although the incidence is quite low.
An 82-year-old man develops a round, fluid-filled cystic structure on the back of his knee that limits the knee's
mobility. This most likely represents an enlargement of which of the following structures?
A. Deep infrapatellar bursa
B. Prepatellar bursa
C. Semimembranous bursa
D. Superficial infrapatellar bursa
E. Suprapatellar bursa
Explanation:
The correct answer is C. The lesion is commonly called a Baker's cyst, and anatomically represents an
enlarged semimembranous bursa. Baker's cysts are more commonly seen at the extremes of age.
The deep infrapatellar bursa (choice A) is on the anterior aspect below the knee.
The prepatellar bursa (choice B) is anterior to the patella.
The superficial infrapatellar bursa (choice D) is on the anterior aspect of the leg below the knee.
The suprapatellar bursa (choice E) is on the anterior aspect of the thigh above the knee.
Biopsy of a 4 mm rough, tan, and slightly raised skin lesion on the face of a 65-year-old man demonstrates
atypical basal cells with eosinophilic cytoplasm but persistent intercellular bridges. The stratum corneum is
thickened and parakeratosis is present; the remainder of the epidermis is thinned. Which of the following features
would probably additionally be seen in the dermis?
A. Benign nevus cells
B. Blue-gray elastic fibers
C. Large numbers of spindle-shaped fibroblasts
D. Malignant nevus cells
E. Touton giant cells
Explanation:
The correct answer is B. The lesion described is an actinic keratosis, which is a common premalignant lesion
caused by solar damage, which also characteristically damages the elastic fibers (changing their color in
stained tissue to blue-gray) of the superficial dermis.
Benign nevocellular nevus cells (choice A) are found in common moles (nevocellular nevi).
Large numbers of spindle-shaped fibroblasts (choice C) are found in dermatofibromas.
Malignant nevus cells (choice D) are found in melanoma.
Touton giant cells (choice E) are found in xanthomas.
A 50-year-old man consults a physician because of a lesion on his nose. On examination, a flesh-colored lesion
about 1 cm in diameter, with a rolled edge and central ulceration, is observed. Which of the following is the most
likely diagnosis?
A. Basal cell carcinoma
B. Eczema
C. Psoriasis
D. Urticaria
E. Verruca vulgaris
Explanation:
The correct answer is A. The description is typical for basal cell carcinoma. These skin cancers typically occur
on sun-exposed areas of the head, neck, and upper trunk. Basal cell carcinoma only rarely metastasizes, but
can become locally mutilating if neglected. When located on the face, it may be difficult to adequately excise
without damaging facial structures.
Eczema (choice B) typically involves a larger area of skin and may cause dryness, discoloration, and thickening
of the involved area. Blistering, erythema, or oozing may also be observed.
Psoriasis (choice C) is characterized by erythematous plaques with a silvery surface.
Urticaria (choice D) causes transient, nonpitting, erythematous wheals.
Verruca vulgaris (choice E), the common wart, causes well-demarcated verrucous papules, often on the hands.
A patient with respiratory symptoms undergoes bronchoalveolar lavage. Which of the following findings would be
most suggestive that congestive heart failure is the cause of the symptoms?
A. Ciliated bronchial epithelial cells
B. Encapsulated pairs of small cocci
C. Hemosiderin-laden macrophages
D. Rhomboid-shaped crystals
E. Single hat-shaped structures that stain with silver stains
Explanation:
The correct answer is C. Hemosiderin-laden macrophages are sometimes called "heart failure cells" because
they are so often seen in congestive heart failure. The congestive heart failure causes increased pulmonary
capillary pressure with tiny hemorrhages. The pulmonary alveolar macrophages phagocytize the dead
erythrocytes and retain the iron from the hemoglobin in the form of hemosiderin.
Ciliated bronchial epithelial cells (choice A) are a normal finding.
The cocci described in choice B are pneumococcus, and can cause pneumonia.
Choice D describes Charcot-Leyden crystals, found in allergic asthma.
Choice E describes the Pneumocystis organism, which can infect AIDS patients.
An adult presents to a physician because of repeated episodes of fainting. EKG fails to disclose an arrhythmia.
Echocardiogram shows a mass in the left atrium that is acting like a "ball valve" to produce intermittent
obstruction of flow. Which of the following would most likely be seen on microscopic examination of the resected
mass?
A. Benign myxoid tumor
B. Benign tumor with gland formation
C. Benign tumor with striated muscle differentiation
D. Malignant tumor with gland formation
E. Malignant tumor with striated muscle differentiation
Explanation:
The correct answer is A. The most common primary cardiac tumor of adults is the benign atrial myxoma. 90% of
these lesions involve the left atrium, where they can produce intermittent obstruction when they flop onto the
mitral valve. Resection is curative.
Neither benign (choice B, adenomas) nor malignant (choice D, adenocarcinomas) primary glandular tumors
usually involve the heart. If adenocarcinoma is seen, suspect metastatic disease.
The rhabdomyoma is the benign tumor with striated muscle differentiation (choice C) that can involve the heart.
This tumor is the most common cardiac tumor of children.
Rhabdomyosarcomas are malignant tumors with striated muscle differentiation (choice E) and typically involve
the head and neck or uterus.
A patient with long-standing, progressive congestive heart failure dies in respiratory distress. The lungs at
autopsy are 3 times their normal weight. Histologically, the alveoli show a proteinaceous granular precipitate,
engorged alveolar capillaries, and hemosiderin-laden macrophages. Other inflammatory cells are inapparent.
Which of the following is the most likely diagnosis?
A. Candida pneumonia
B. Pneumococcal pneumonia
C. Pneumocystis pneumonia
D. Pulmonary edema
E. Pulmonary infarction
Explanation:
The correct answer is D. These are the characteristic findings of pulmonary edema. The edema fluid is
apparent as a proteinaceous granular precipitate after histologic processing of the tissue. Hemosiderin-laden
macrophages in the tissue, called "heart failure cells," are the end result of ingestion of red blood cells by
alveolar macrophages. Pulmonary edema develops in heart failure when the pulmonary venous pressure rises
and the capacity for the tissue to reabsorb the fluid into the venous system is exceeded.
In Candida pneumonia (choice A), fungal hyphae and spores would be described.
In pneumococcal pneumonia (choice B), gram-positive cocci (Streptococcus pneumoniae) would be described.
In Pneumocystis pneumonia (choice C), hat-shaped, silver-stained cysts would be described.
In pulmonary infarction (choice E), ischemic necrosis of alveoli would be described.
A 3-year-old child is brought to the emergency room by her concerned parents. They state the girl has been
complaining of a severe headache and has had two episodes of vomiting. On physical examination, there is bilateral papilledema and an impaired level of consciousness. Emergency contrast CT scan demonstrates displacement of the ventricular system by a multilocular "mass" with well-defined white high-attenuation rings around black low-attenuation centers. The lesion involves the cerebellum. To which of the following conditions i this lesion most likely related?
A. Bacteremia following tooth extraction
B. Bacterial meningitis
C. Lung abscess
D. Otitis media
E. Sinusitis
Explanation: