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Posted by baba from IP 24.34.79.246 on August 06, 2014 at 03:44:35:

Two weeks after receiving an allogeneic bone marrow transplant for treatment of acute myelogenous leukemia, a
45-year-old man develops fever, intractable diarrhea, generalized rash, and non-productive cough. Chest x-ray films
show bilateral interstitial infiltrates in the lung. The patient dies of overwhelming sepsis and multiorgan failure.
Autopsy investigations reveal cytomegalovirus pneumonia, and extensive single cell necrosis in the intestinal
epithelium and skin. This complication of bone marrow transplantation is principally mediated by which of the
following cells?


A. B-lymphocytes of bone marrow graft

B. Leukemic cells

C. Natural killer cells of recipient

D. T-lymphocytes of bone marrow graft

E. T-lymphocytes of recipient


Explanation:

The correct answer is D. Allogeneic bone marrow transplantation has become a frequent therapeutic approach to
a variety of conditions, including leukemic diseases. The patient undergoing bone marrow transplantation is
profoundly immunosuppressed and prone to developing opportunistic infections. The clinical picture described in
this case is consistent with graft versus host disease (GVHD), in which T cells (both helper and suppressor cells) of
the engrafted marrow react against the recipient's antigens, thus triggering inflammation and injury to the host
tissues. The most severely affected organs include the immune system, gastrointestinal tract, liver, skin, and lungs.
This complication may be acute (this case) or chronic. CMV pneumonia is a frequent fatal complication in the acute
stage. The chronic stage is characterized by progressive fibrosis of affected organs.

B-lymphocytes of a bone marrow graft (choice A) do not play a significant role in GVHD.

Leukemic cells (choice B) may give rise to recurrence of the original disease, which must be distinguished from
GVHD. The combination of skin rash and opportunistic infections strongly favor GVHD. In addition, single cell
necrosis in the epithelia of skin, GI tract, and liver is highly characteristic of GVHD.

Natural killer cells of the recipient (choice C) and T-lymphocytes of the recipient (choice E) play a crucial role in
mediating rejection of allogeneic marrow transplants.


A 10-year-old boy has a long history of recurrent infections. These have included pneumonia, suppurative
lymphadenitis, persistent rhinitis, dermatitis, diarrhea, and perianal abscesses. Involved organisms have included
Staphylococcus aureus, Serratia, Escherichia coli, and Pseudomonas. Biopsy of skin and lymph nodes have
demonstrated granulomatous lesions, even though the only species isolated were those noted above.
Immunoglobulin levels are higher than normal. Which of the following findings would be most helpful in establishing
the diagnosis?


A. Absent B cells and normal numbers of T cells

B. Deficient nitroblue tetrazolium dye reduction in neutrophils

C. High serum IgM and very low serum IgG

D. Very low CD11 on the surface of white blood cells

E. Very low serum calcium levels


Explanation:

The correct answer is B. This child's condition is chronic granulomatous disease, a usually x-linked recessive
condition characterized by inadequate production of hydrogen peroxide, superoxide, and other activated oxygen
species in neutrophils. The nitroblue tetrazolium dye reduction test demonstrates the failure of the defective
neutrophils to produce these products. The clinical result of the enzymatic defect is that the neutrophils can
phagocytize but not kill bacteria. Affected individuals are plagued with multiple, poorly healing infections to which
their bodies respond with granuloma formation to remove organisms that would normally be controlled by
neutrophils. These patients are usually treated with intermittent or continuous antibiotics; bone marrow transplant
and interferon therapy have also been used.

Absent B cells and normal numbers of T cells (choice A) suggests X-linked agammaglobulinemia.

High serum IgM and very low serum IgG (choice C) suggests hyper IgM immunodeficiency.

Monoclonal anti-CD11 is used to diagnose leukocyte adhesion deficiency, in which the CD11 antigen on the
surface of white blood cells (choice D) is missing. This disorder causes a severe form of immunodeficiency that
usually results in death by age 5.

Serum calcium levels (choice E) can be markedly decreased in DiGeorge syndrome.


A 52-year-old man is recuperating in a hospital after having sustained a recent cerebrovascular accident that
damaged part of his right temporal lobe. Once the patient has recuperated from the immediate effects of his stroke,
to which of the following psychiatric disorders will he be most predisposed?


A. Conversion disorder

B. Mania

C. Major depressive disorder

D. Schizophrenia

E. Substance abuse


Explanation:

The correct answer is C. Any event that affects the vasculature, such as a myocardial infarction or a
cerebrovascular accident (CVA), has been shown to increase the risk of major depressive disorder in the months
following such an event. The pathophysiology of such a development is unclear, but is thought to be related to the
effects of serotonin on vascular physiology.

Conversion disorder (choice A) is a disorder of physiological complaints that are related to social stressors; it has
not shown to be related to vascular events.

Mania (choice B) is a syndrome of increased elevated mood, irritability, and grandiosity associated with bipolar
affective disorder, but not associated with CVAs.

Schizophrenia (choice D) is a thought disorder characterized by disturbances in language, thought content, and
perception. It is not related to CVA.

Substance abuse (choice E) is not increased in incidence in individuals after cerebrovascular accident.


A 38-year-old woman comes to the physician for an annual examination and Pap smear. She has no complaints. She
has a regular period every month. She is sexually active with her husband. She has migraine headaches and is
status post a tubal ligation. She states that she uses numerous alternative medications for mood, sleep, and disease
prevention. Examination, including pelvic and breast examination, is unremarkable. Which of the following is an
appropriate question to ask this patient?


A. Does your husband know you are using these alternative medications?

B. Do you realize how dangerous alternative medicines are?

C. Which alternative medications do you use?

D. Why don't you stick with traditional medicines?

E. Why haven't you revealed your use of alternative medications before?


Explanation:

The correct answer is C. Some estimates indicate that roughly 50% of Americans use some forms of
complementary and alternative medicine (CAM). The categories of these include mind-body interventions, such as
yoga, alternative systems of medical practice such as Chinese medicine, pharmacologic treatments such as
medicinal plants, herbal medicine such as St. John's wort, diet therapies such as vegetarianism, manual healing
methods such as massage, and bioelectromagnetic applications such as magnets for musculoskeletal pain. It is
essential for the physician to work with the patient regarding the use of CAM. The first step is to find out which
methods the patient uses. This patient has told the physician that she uses alternative medications. Many patients
do not offer this information, assuming that the usual physician will not support CAM. It is therefore important to ask
the patient whether she is using, or considering using, CAM. Because the field of CAM is so broad, it is essential to
ask which types of CAM the patient uses. One cannot assume that all alternative therapies are equivalent. Thus,
the most appropriate question to ask this patient is "Which alternative medications do you use?" This is a
non-threatening question that will allow her to further detail her use.

To ask, "Does your husband know you are using these alternative medications?" (choice A) is inappropriate. The
physician's role is to care for the patient. Whether the patient reveals her use of alternative medicines to her
husband is not the prime concern to the physician. This question is more likely to create conflict than reveal needed
information for the physician.

To ask, "Do you realize how dangerous alternative medicines are?" (choice B) is incorrect. This question is
confrontational and judgmental. Many alternative therapies are safe and effective.

To ask, "Why don't you stick with traditional medicines?" (choice D) is inappropriate. If a patient has a condition
and there is a remedy from the conventional medical system (known as allopathy in North America) available, then it
is reasonable to offer this remedy as a possibility for the patient. However, inquiring as to why the patient doesn't
"stick" with traditional medicine is likely to cause confrontation and a worsening of the patient-doctor relationship.

To ask, "Why haven't you revealed your use of alternative medications before?" (choice E) is also somewhat
challenging and confrontational. Perhaps the patient did not think a conventional physician would be accepting of
CAM. The important step at this point is to identify the medications and discuss their risks, benefits, and side effects
with the patient, as one would with traditional medications.


A 46-year-old woman, who had always been in good health, comes in because of the sudden onset of very severe
back and leg pain that she experienced 2 hours ago when attempting to lift a heavy object. She says that she felt "a
bolt of lightening" running down the back of her leg, and she still has very severe pain that prevents her from walking
or moving. The pain is exacerbated by coughing, sneezing, or straining. She keeps the affected leg flexed; straight
leg raising gives her excruciating pain. She has good sphincteric tone and intact sensation in the perineum. Once the
diagnosis is confirmed with the appropriate studies, which of the following will be the most appropriate treatment?


A. Analgesics and bed rest for about 3 weeks

B. Appropriate antibiotics

C. Body cast for 3-6 months

D. Radiotherapy to the affected area

E. Surgical decompression


Explanation:

The correct answer is A. The clinical features are those of a herniated lumbar disc. The diagnosis should be
confirmed with an MRI, and then the patient should be treated conservatively with bed rest. Most patients get better
with this simple approach.

Giving antibiotics (choice B) assumes an infectious process. Infections can occur in the lumbar spine or the discs,
but their symptoms do not start suddenly, like this vignette describes.

A body cast (choice C) might be needed for fractures, scoliosis, or other spinal pathology, but casting is not
needed for an extruded disc.

Radiotherapy (choice D) assumes a neoplastic process. Although a weakened bone may indeed rupture suddenly,
such patients are usually known to have had the kind of tumor that is likely to metastasize to bone (in women,
breast cancer would lead the list), and would have been complaining of localized bony pain before the process gets
to the point of fracture.

Surgical decompression (choice E) would have been required if she had sphincteric deficits or perineal anesthesia.


A 38-year-old woman presents complaining of a burning discomfort in the substernal region. The symptoms are
worse following any meal and after reclining for sleep at night. She has a history of Raynaud phenomenon and mild
hypertension. On physical examination, her blood pressure is 162/94 mm Hg, pulse is 78/min, and respirations are
16/min. She is afebrile. There are multiple facial telangiectasias on both cheeks, and she has taut skin on both
hands. The remainder of her musculoskeletal examination is unremarkable. Which of the following is most likely
responsible for her chest discomfort?


A. Coronary vasospasm

B. Costochondritis

C. Esophageal hypomotility

D. Hypertension of the lower esophageal sphincter

E. Pulmonary fibrosis


Explanation:

The correct answer is C. This patient has typical features of progressive systemic sclerosis (systemic
scleroderma), as demonstrated by her Raynaud phenomenon, facial telangiectasias, taut skin, and hypertension. (If
she later develops calcinosis, she will have exhibited the characteristic features of the CREST variant of
progressive systemic sclerosis.) The symptoms she describes are typical of gastroesophageal reflux disease, which
is seen in these patients as a result of esophageal hypomotility, as well as fibrosis of the lower esophageal
sphincter (LES), which causes reduced lower esophageal sphincter pressures. The underlying disease process in
progressive systemic sclerosis is a small vessel obliteration that leads to secondary diffuse fibrosis. When this
affects the esophagus, the esophageal musculature no longer contracts effectively. No specific therapy is available
for the esophageal dysfunction of progressive systemic sclerosis, and patients are treated with anti-esophageal
reflux regimens (e.g., antacids, H2 blockers, frequent small feedings, and elevated head of bed) and periodic
(mechanical) dilation of any esophageal strictures that develop. Remember also that the long history of reflux
esophagitis will predispose for development of Barrett's esophagus with the risk of progression to esophageal
cancer.

Scleroderma patients are at risk for coronary artery disease (choice A), but her symptoms (particularly the tie to
ingestion of food) are not typical of coronary ischemia.

Costochondritis (choice B) is generally diagnosed with tenderness over palpation of the costochondral joints and is
not associated with scleroderma.

As stated above, these patients develop reduced pressures in the LES and not hypertension of the LES (choice
D).

Pulmonary fibrosis (choice E) can be seen in these patients, but her symptoms (particularly the tie to ingestion of
food) are of gastroesophageal reflux and not of pulmonary disease.


A 29-year-old professional tennis player presents with severe diarrhea and abdominal cramps over the past week.
She has been in excellent health, and her only medical history is a urinary tract infection, treated 2 weeks ago with
amoxicillin. Three days ago, she began having left lower quadrant abdominal cramps, followed by diarrhea that has
become increasingly profuse. Over the past 24 hours, her temperature has increased to 38.4 C (101.1 F). Her
physical examination is remarkable for moderate periumbilical and left lower quadrant tenderness. Her stool is guaiac
negative. Which of the following would most likely be seen on sigmoidoscopy?


A. Deep rectal ulcers with normal sigmoid mucosa

B. Multiple sigmoid diverticula

C. Rectosigmoid edema and patchy exudates

D. Rectosigmoid stricture

E. Sessile sigmoid mass


Explanation:

The correct answer is C. This patient has an acute colitis after the use of antibiotics. This is due to overgrowth of
Clostridium difficile and can cause a colitis with the characteristic pseudomembranes, which are seen with
sigmoidoscopy as patchy exudates. Microscopically, the exudates are composed of necrotic mucosal cells,
inflammatory cells, bacteria, and fibrin. Although almost any antibiotic can lead to C. difficile infection, commonly
implicated culprits include clindamycin, broad spectrum penicillins such as ampicillin and amoxicillin (as in this
patient), and cephalosporins. Initial treatment is with cessation of the original antibiotic, if it is still being used.
Antiperistaltic drugs are contraindicated as they tend to prolong the illness. Most cases subside spontaneously
within 10-12 days without other specific therapy.

The colitis usually seen in a patient with pseudomembranous colitis is a diffuse mucosal process and does not
typically reveal localized deep ulcers (choice A).

Although left lower quadrant cramps may be seen with diverticula, they are generally seen in the older population
and do not present with diarrhea (choice B).

There are no obstructive symptoms in this patient's history to suggest that she would have any strictures (choice
D).

Similarly, this acute onset of diarrhea would not be expected to be the result of a sessile sigmoid mass (choice E).


A 60-year-old woman consults a physician because of weakness, headaches, dizziness, and tingling in her hands
and feet. Physical examination demonstrates multiple areas of bruising on the back of her forearms and shins. On
specific questioning, she reports having had five nosebleeds in the past two months, which she had attributed to "dry
air". Blood studies are drawn which show a platelet count of 1.2 106/L, a red cell count of 5.1 106/L, and a
white count of 10,500/L with a normal differential count. Review of the peripheral smear demonstrates many
abnormally large platelets, platelet aggregates, and megakaryocyte fragments. No abnormal red or white blood cells
are seen. Philadelphia chromosome studies are negative. Which of the following is the most likely diagnosis?


A. Chronic myelogenous leukemia

B. Myelofibrosis

C. Polycythemia vera

D. Primary thrombocythemia

E. Secondary thrombocythemia


Explanation:

The correct answer is D. The most likely diagnosis is primary (essential) thrombocythemia. The condition is due
to a clonal abnormality of a multipotent hematopoietic cell that produces megakaryocytic hyperplasia with resultant
increased platelet count. Since the platelets are often abnormal, either a thrombotic or a hemorrhagic tendency may
be seen. The platelet count may be as low as 500,000/L or greater than 1,000,000/L. The clinical presentation
and laboratory findings illustrated in the question stem are typical. The other choices listed commonly must be
excluded before a diagnosis of primary thrombocythemia is confirmed.

Chronic myelogenous leukemia (choice A) can be a cause of increased platelet count, but the absence of either a
Philadelphia chromosome or a markedly increased white count argues against this possibility.

Myelofibrosis (choice B) can also cause thrombocythemia, but would likely show some abnormally shaped (often
tear drops) red cells.

Polycythemia vera (choice C) can also cause thrombocythemia, but would be associated with an increased red cell
mass.

Secondary thrombocythemia (choice E) is a reactive process that may occur in a variety of settings including
chronic inflammatory disorders, acute infection, hemorrhage or hemolysis, tumors, iron deficiency, or splenectomy.
Abnormal platelet forms are not usually seen on smears from these patients and platelet function tests are usually
normal.


A young man is shot with a .45 caliber revolver, point blank in the lower abdomen, just above the pubis. The
entrance wound is at the midline, and there is no exit wound. X-ray films show the bullet embedded in the sacral
promontory, to the right of the midline. Digital rectal examination and proctoscopic examination are negative, but he
has gross hematuria. He is hemodynamically stable. Which of the following is the most appropriate next step in
management?


A. CT scan of the abdomen

B. Intravenous pyelogram

C. Retrograde cystogram

D. Diagnostic peritoneal lavage

E. Exploratory laparotomy


Explanation:

The correct answer is E. He has an obvious indication for exploratory laparotomy: a gunshot wound to the
abdomen. He also has evidence of injury to the urinary bladder, but that will be dealt with at the same time that
other intraabdominal injuries are found and repaired.

CT scan (choice A) would not change the surgical approach and the surgical indication. CT scan is called for in
cases of blunt trauma to diagnose intraabdominal bleeding and to identify intraabdominal injuries.

Intravenous pyelogram (choice B) would indeed show the bladder injury, as would a retrograde cystogram (choice
C). However, we already know clinically that there is a bladder injury: we know the trajectory of the bullet and we
have blood in the urine.

Diagnostic peritoneal lavage (choice D) is used to diagnose intraabdominal bleeding in blunt trauma, when the
patient is not stable enough to be taken to the CT scanner. In many centers the diagnostic peritoneal lavage has
been replaced by sonogram done in the emergency department by the trauma team.


An AIDS patient develops symptoms suggestive of a severe, persistent pneumonia with cough, fever, chills, chest
pain, weakness, and weight loss. The patient does not respond to penicillin therapy, but goes on to develop very
severe headaches. The presence of focal neurologic abnormalities leads the clinician to order a CT scan of the head.
This demonstrates several metastatic brain abscesses. Biopsy of one of these lesions demonstrates beaded,
branching, filamentous gram-positive bacteria that are weakly acid fast. Which of the following is the most likely
causative organism?


A. Actinomyces

B. Aspergillus

C. Burkholderia

D. Francisella

E. Nocardia


Explanation:

The correct answer is E.Nocardia asteroides is an aerobic soil saprophyte that can cause acute or chronic
infectious disease often characterized by granulomatous-suppurative lesions that may become widely disseminated.
Many, but not all, patients have underlying causes for immunodeficiency, including advanced age, lymphoreticular
malignancies, organ transplantation, high dose corticosteroid therapy, or (increasingly commonly) AIDS.
Disseminated nocardiosis usually starts as a pulmonary infection that can resemble either a severe pneumonia or
tuberculosis. Once dissemination occurs, metastatic brain abscesses are particularly common, occurring in as many
as 1/3 of patients with nocardiosis. Nocardiosis is treated with sulfa drugs, such as sulfadiazine or
trimethoprim-sulfamethoxazole, for periods of months.

Actinomyces (choice A) is very similar to Nocardia, but is not acid-fast.

Aspergillus(choice B) is a fungus.

Burkholderia(choice C)pseudomallei is a gram-negative bacillus that causes melioidosis, which is characterized by
lung involvement or disseminated infection.

Francisella(choice D)tularensis causes tularemia, which is usually acquired by contact with infected wild rabbits.


A family physician cares for a family consisting of a 45-year old husband, 43-year-old wife and a 12-year-old
daughter. The family reports that recently the 77-year-old maternal grandmother who lived with them died after a
prolonged respiratory infection. Autopsy subsequently confirms that she had active pulmonary tuberculosis at the
time of death. The organism tested sensitive to all anti-tuberculosis drugs. In responding to the grandmother's illness,
which of the following is the most appropriate step in management?


A. Obtain leukocyte counts on all family members

B. Obtain sputum cultures for acid fast bacilli

C. Obtain chest computerized tomograms on all members

D. Place protein purified derivative (PPD) test on all members

E. Schedule bronchoscopy lavage for the adults


Explanation:

The correct answer is D. The immediate step is to screen the family for TB exposure. The most effective manner
in which to accomplish this is by placing PPDs on all members and working up those with a positive test.

The white cell count may be elevated for a variety of reasons and would not necessarily help in diagnosis or
management (choice A).

Sputum cultures will take 6 months to grow and may be too cumbersome to obtain (choice B).

Chest CT scans may show the tuberculosis lesion but a more effective method would be to place the PPD and
perhaps then scan those with a positive test (choice C).

A bronchoscopy would be too invasive an option at this point (choice E).


A 38-year-old woman, gravida 1, para 0, at 8 weeks' gestation comes to the physician for a prenatal visit. She has
had no bleeding from the vagina or abdominal pain and no complaints. She has a long history of migraine headache
and recently developed peptic ulcer disease (PUD). Examination shows a nontender 8-week sized uterus but is
otherwise unremarkable. The patient is very concerned that her migraine headaches and peptic ulcer disease will
make her pregnancy intolerable. Which of the following is the most appropriate response?


A. Pregnancy is associated with improvement of migraines and PUD.

B. Pregnancy is associated with worsening of migraines and PUD.

C. Pregnancy is associated with worsening migraines and improved PUD.

D. Pregnancy is associated with improved migraines and worsened PUD.

E. Pregnancy has no effect on migraines or PUD.


Explanation:

The correct answer is A. Within the last decade it has been recognized that Helicobacter pylori plays a central
role in the pathogenesis of chronic gastritis and peptic ulcer disease (PUD). Acid secretion is also known to play a
role. During pregnancy, gastric acid secretion is reduced and there is also a decrease in gastric motility. Pregnancy
is also associated with increased mucus secretion, which is felt to have a protective effect on the gastrointestinal
tract. Because of these physiologic changes during pregnancy, active peptic ulcer disease during pregnancy is
extremely uncommon during pregnancy. Women rarely develop PUD in pregnancy and women with PUD note
considerable improvement. Estimates are that 90% of patients with active PUD will experience remission during
pregnancy. However, once the pregnancy is completed, almost all women will experience recurrence in the next few
years.

A significant portion (up to 20%) of women experience migraine headaches during their lives, so issues regarding
migraines and pregnancy are not uncommon. As with PUD, there is usually a dramatic improvement of migraines
during pregnancy. Estimates are that 70% of women with migraines will have improvement. However, it is
interesting to note that some women will have their first experience with migraine during pregnancy and may only
experience migraine with pregnancy. Migraine headache during pregnancy should be treated with acetaminophen
and antiemetics. Codeine or meperidine may be given for severe headaches. Ergotamine preparations should be
avoided in pregnancy. The safety of sumatriptan during pregnancy has not been established, so pregnant patients,
at present, should seek alternative medications.

To state that pregnancy is associated with worsening of migraines and PUD (choice B), worsening migraines and
improved PUD (choice C), or improved migraines and worsened PUD (choice D) is incorrect. As explained above,
pregnancy is associated with both improved migraines and PUD.

To state that pregnancy has no effect on migraines or PUD (choice E) is also incorrect. These two illnesses are
examples of the profound effect that pregnancy can have on certain conditions.

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