Day 21

Question 1

Q26-A 59-year-old military commander has been attacked with nerve gas. He presents with salivation, lacrimation, urination, defecation, and shortness of breath. His pupils are constricted.
What is the first step in the management of this patient?

A-Atropine
B-Decontaminate (wash) the patient
C-Remove his clothing
D-Pralidoxime
E-No therapy is effective

Answer 1

Ans: A. Atropine blocks the effects of acetylcholine that is already increased in the body. Atropine dries up respiratory secretion. Although removing clothes and washing the patient to prevent further absorption is good, this will do nothing for symptoms that are already occurring. Pralidoxime is the specific antidote for organophosphates. Pralidoxime reactivates acetylcholinesterase. It does not work as instantaneously as atropine.

Question 2

Q26-A 28-year-old man sustains head trauma in a motor vehicle accident. A large epidural hematoma is found. Immediately after intubation and mannitol, surgical evacuation is successfully performed.
Which of the following will most likely benefit the patient?

A-Repeated doses of mannitol
B-Continued hyperventilation
C-Proton pump inhibitor (PPI)
D-Nimodipine
E-Dexamethasone

Answer 2

Ans: C. A PPI is given to prevent stress ulcers. The only clear indications for stress ulcer prophylaxis are:
• Head trauma
• Burns
• Endotracheal intubation
• Coagulopathy (platelets below 50,000 or INR over 1.5) with respiratory failure
Hyperventilation has very short-term efficacy and is probably ineffective after 24 hours. Nimodipine prevents stroke after subarachnoid hemorrhage. Dexamethasone, a potent glucocorticoid, is ineffective for intracranial hemorrhage.

Question 3

Q28-What is the most common cause of death several days to weeks after a burn?

A- Infection
B-Renal failure
C-Cardiomyopathy
D-Lung injury
E-Malnutrition

Answer 3

Ans: A. Because of loss of skin, there is a massive loss of body fluids and albumin. Fluid loss, if fatal, will occur immediately. After several days, the loss of the protective barrier of the skin leads to infection with Staphylococcus. Rhabdomyolysis causes renal failure, especially combined with volume depletion decreasing renal perfusion. This is not the most common cause of death. Lung injury is an immediate cause of death.

Question 4

Q29-A woman comes to the office for routine evaluation. She is found to have a pulse of 40 and an otherwise completely normal history and physical examination.
What is the most appropriate next step in the management of this patient?

A-Atropine
B-Pacemaker
C-EKG
D-Electrophysiology studies
E-Epinephrine
F-Nothing; reassurance

Answer 4

Ans: C. Bradycardia is common. The normal heart rate is between 60 and 100, but some people just normally have a heart rate that is below 60. Bradycardia can also be the initial presentation of third-degree or “complete” heart block. An EKG is mandatory to distinguish the cause of bradycardia. The most common wrong answer is “do nothing.” If you confirm that this is an asymptomatic sinus bradycardia, then the answer is “reassurance” or “do nothing.” Atropine is the answer for an acutely symptomatic patient with signs of hypoperfusion. Pacemaker is used for all patients with third degree AV block. Epinephrine is dangerous, especially since ischemia is such a common cause of bradycardia. Isoproterenol is an old, rarely used nonspecific beta agonist that speeds up the heart rate but increases ischemia.

Question 5

Q30-A 60-year-old woman is admitted to the hospital with an acute myocardial infarction. On the second hospital day she develops sustained ventricular tachycardia even though she is on aspirin, heparin, lisinopril, and metoprolol. What is the most appropriate next step in management?

A-Increase the dose of metoprolol
B-Add diltiazem
C-Angiography for angioplasty or bypass
D-Implantable defibrillator
E-EP studies

Answer 5

Ans: C. The most common cause of death in the 72 hours surrounding an acute myocardial infarction is a ventricular arrhythmia. Manage arrhythmias from ischemia by correcting the ischemia. Don’t put in an implantable defibrillator for an arrhythmia you can prevent or fix by eliminating the cause.

Question 6

Q31-Which of the following tests would you do for this patient to determine a risk of recurrence?

A-EP studies
B-Echocardiography
C-MUGA scan (nuclear ventriculography)
D-Ventilation/perfusion scan
E-Tilt-table testing

Answer 6

Ans: B. Left ventricular function is the most important correlate of the risk of recurrence. Although nuclear ventriculography is more accurate, you would never do this test first or before you had done an echocardiogram. Tilt-table testing assesses orthostasis and autonomic instability. Tilt-table testing is done to evaluate syncope of unclear etiology particularly when there are signs of postural instability. EP studies are used when you are not certain of the diagnosis. EP studies are done if there are short runs or ventricular tachycardia or unexplained syncope and you want to see if you can induce sustained ventricular tachycardia. If the echo shows a normal ejection fraction her risk of recurrence of ventricular arrhythmia is small.

Question 7

Q32-A 75-year-old man has his third syncopal episode in the last 6 months.An EKG done in the field shows ventricular tachycardia. His stress test is normal.
What is the most appropriate next step in the management of this patient?

A-Metoprolol
B-Diltiazem
C-Angiography
D-Implantable defibrillator
E-EP studies

Answer 7

Ans: D. There is no point in doing an EP study when the EKG shows a clear etiology of the syncope. We already know he has an unprovoked ventricular rhythm disorder. Metoprolol is not sufficient when syncope or sudden death has occurred. Calcium channel blockers like diltiazem are useless in preventing or treating ventricular tachycardia The stress test is normal and there is no chest pain, so there is no point in doing angiography. An implantable defibrillator will prevent the next episode of sudden death or syncope.

Question 8

Q33-A 75-year-old man has his third syncopal episode in the last 6 months.An EKG done in the field shows ventricular tachycardia. His stress test is normal.
What is the most appropriate next step in the management of this patient?

A-Metoprolol
B-Diltiazem
C-Angiography
D-Implantable defibrillator
E-EP studies

Answer 8

Ans: D. There is no point in doing an EP study when the EKG shows a clear etiology of the syncope. We already know he has an unprovoked ventricular rhythm disorder. Metoprolol is not sufficient when syncope or sudden death has occurred. Calcium channel blockers like diltiazem are useless in preventing or treating ventricular tachycardia The stress test is normal and there is no chest pain, so there is no point in doing angiography. An implantable defibrillator will prevent the next episode of sudden death or syncope.

Question 9

Q34-A 48-year-old man has intermittent episodes of palpitations, light headedness, and near-syncope. His EKG is normal. The echo shows an ejection fraction of 42%. Holter monitor shows several runs of wide complex tachycardia lasting 5 to 10 seconds.
Which of the following is most likely to benefit this patient?

A-Pacemaker placement
B-Digoxin
C-Warfarin
D-EP studies
E-Swan-Ganz catheter

Answer 9

Ans: D. EP studies are useful in detecting a source of ventricular arrhythmia. If you can readily induce sustained ventricular tachycardia, this person would benefit from an implantable defibrillator. He may have episodes of sustained ventricular tachycardia causing his symptoms that have not been detected by the Holter monitor. Digoxin is useless for ventricular arrhythmias. Swan-Ganz is a right heart catheter that assesses intracardiac pressure and cardiac output.

Question 10

Q34-A man has an ugly house that you offer to paint for free in his favorite color. Everyone on the neighborhood council agrees that the house is ugly and that what you are offering is clearly superior to what he has. The man would have no financial or other obligation in exchange. He understands everything you are offering, including the clear benefit to him. The man still refuses.
What do you do?

A-Honor the man’s wishes: no paint job
B-Paint his house against his will
C-Ask the neighborhood council to consent to the paint job
D-Get a psychiatric evaluation on the man
E-Get a court order to allow the paint job

Answer 10

Ans: A. This seemingly silly example will allow you to answer the majority of questions. Cost and benefit and the common good are not as important as the autonomy individuals have to just do what they want with their own property. A community board is like an ethics committee. You cannot wait until a person loses consciousness or is sedated to then perform the test or treatment.

Question 11

Q35-A man comes to the emergency department after a motor vehicle accident that causes a ruptured spleen. At present, he is still fully conscious. He understands that he will die without splenectomy, and that he will live if he has the splenec tomy. He refuses the repair and refuses blood transfusion. His whole family is present, including his brother, who is the healthcare proxy. The family and the proxy both the agent (the person) and the document completed only a few weeks ago-clearly state, “Everything possible should be done, including surgery.”
What do you do?

A-Honor his current wishes, no surgery
B-Wait until he loses consciousness, then perform the surgery
C-Psychiatric consult
D-Ethics committee
D-Emergency court order
F-See if there is consensus from the family

Answer 11

Ans: A. You must follow the last known wishes of the patient, even if they are verbal, and even if they contradict the written proxy. You cannot wait until his consciousness is lost, then go against his wishes. The family cannot go against his clearly stated wishes, even if the whole family is in agreement. The proxy cannot go against his wishes. There is no need for a psychiatric consultation if it is clear that the patient has the capacity to understand the problem and the consequences of refusing treatment. A court order or ethics committee cannot contradict an adult with capacity to understand. If a patient write one thing and 10 minutes later changes his mind, you go with whatever the last clear wishes are.

Question 12

Q36-19 year female with painless lesion on vulva for 4 days. Monogamous and no contraception used. 10-mm, sharply demarcated, elevated, round lesion on right labium major. Base of the lesion is smooth and nonpurulent. Which is the likely organism?

A-Chlamydia
B-Gardnerella Vaginitis
C-Haemophilus ducrey
D-Treponema pallidum
E-Neisseria Gonorrhea

Answer 12

Ans: D

Question 13

Q37-Baby in NICU has a heart rate of 300, good blood pressure level, what should you do?

A-DC shock
B-IV Amidarone
C-Digoxin
D-Carotid massage

Answer 13

Ans: D

Question 14

Q38-Female patient with hirsutism, obesity, infertility.Ultrasound show multiple ovarian follicles. Diagnosis:

A-Klinefelter’s syndrome
B-Asherman’s syndrome
C-Kallman syndrome
D-Stein-leventhal syndrome

Answer 14

Ans: D. Polycystic ovary syndrome(PCOS)-other names are Hyperandrogenic anpvulation or stein-Leventhal syndrome. is a set of symptoms due to elevatedandrogens(male hormones) in females.Signs and symptoms of PCOS include irregular or nomenstrual periods,heavy periods,excess body and facial hair,acne, pelvic pain,difficulty getting pregnant, andpatches of thick, darker, velvety skin.Associated conditions includetype 2 diabetes,obesity,obstructive sleep apnea,heart disease,mood disorders, andendometrial cancer.
PCOS is due to a combination of genetic and environmental factors.Risk factors includeobesity, a lack of physical exercise, and a family history of someone with the condition. Diagnosis is based on two of the following three findings: noovulation, highandrogenlevels, andovarian cysts.Cysts may be detectable byultrasound.Other conditions that produce similar symptoms includeadrenal hyperplasia,hypothyroidism, andhigh blood levels of prolactin.
PCOS has no cure.Treatment may involve lifestyle changes such as weight loss and exercise.Birth control pillsmay help with improving the regularity of periods, excess hair growth, and acne.Metforminandanti-androgensmay also help. Other typical acne treatments and hair removal techniques may be used.Efforts to improve fertility include weight loss,clomiphene, or metformin. In vitro fertilizationis used by some in whom other measures are not effective.
PCOS is the most commonendocrine disorderamong women between the ages of 18 and 44. It affects approximately 2% to 20% of this age group depending on how it is defined.When someone is infertile due to lack of ovulation, PCOS is the most common cause.

Question 15

Q39-Which of the following antipsychotic associated with weight gain.

A-Respiridone
B-Quitapine
C-Olanzapine
D-Ziprasidone

Answer 15

Ans: C. Olanzapine, sold under the trade nameZyprexaamong others, is anatypical antipsychoticprimarily used to treatschizophreniaandbipolar disorderFor schizophrenia, it can be used for both new onset disease and long-term maintenance.It is taken by mouth or byinjection into a muscle.
Common side effects includeweight gain,movement disorders, dizziness, feeling tired, constipation, and dry mouth.Other side effects includelow blood pressure with standing,allergic reactions,neuroleptic malignant syndrome,high blood sugar,seizures,gynecomastia,erectile dysfunction, andtardive dyskinesia.In older people withdementia, its use increases the risk of death.Use in the later part ofpregnancymay result in amovement disorderin the baby for some time after birth.Although how it works is not entirely clear, it blocksdopamineandserotonin receptors

Question 16

Q40-One year following a difficult birth, which was accompanied by considerable blood loss, a 30-year-old woman comes to the physician complaining of profound fatigue, loss of appetite, cold intolerance, and constipation. She denies feelings of depression, but she feels constantly apathetic and tired and has no sexual drive. Her menses have not resumed after delivery. Her blood pressure is 100/65 mm Hg. Examination reveals dry and pale skin, with thin and brittle hair. Which of the following is the most likely diagnosis?

A- Postpartum depression
B-Primary adrenal insufficiency
C- Primary hypothyroidism
D- Sheehan syndrome

Answer 16

Ans: D-The key is sheehan syndrome, the clue is history typical

Question 17

Q41- A 45-year-old woman comes to the clinic with a 4-month history of headaches and changes in her vision. She has been previously healthy and has not been on any medications. On examination, she is found to have a small field defect in both eyes. The diagnosis of a pituitary microadenoma is entertained. Which of the following is the most sensitive diagnostic study for this condition?

A-Computerized tomography (CT) scans
B-Insulin-tolerance test
C-Magnetic resonance imaging (MRI)
D- Serum prolactin measurement
E-Visual field examination

Answer 17

Ans: C. MRI with gadolinium is considered the most sensitive test for detecting microadenoma. The test can reveal microadenomas in 20% of normal women.
CT scans can be quite sensitive in the detection of microadenomas, but MRIs are even more so (choice A).

Insulin-resistance as a result of impaired growth hormone response to insulin-induced hypoglycemia is not as common (choice B).

The serum prolactin level is elevated due to hypersecretion in 30-50% of patients
(choice D).
For the optic chiasm to be compressed in order to cause visual field changes, the
microadenoma would have to be quite large, and a screening test based on this finding would be ineffective (choice E).

Question 18

Q42- A 50-year-old man is admitted to the hospital after sustaining an acute myocardial infarction. Eight hours after this event, his blood pressure is 70/50 mm Hg, and his pulse is 45/min. An electrocardiogram reveals sinus rhythm. Which of the following is the most appropriate intervention?

A-Administer atropine intravenously
B-Administer dobutamine
C- Administer a beta blocker
D- Insert a transvenous pacemaker
E-Perform cardiac catheterization

Answer 18

Ans: A. The patient is hypotensive and bradycardic. This suggests a vagal response, and administering an anticholinergic agent, such as atropine, is the correct treatment.

Inotropic agents, such as dobutamine (choice B), are not indicated at this time, since the patient is hypotensive. If other methods of resuscitation, such as IV hydration, fail, then a pressor is indicated.

A beta blocker, such as metoprolol (choice C), is indicated in the setting of a myocardial infarction, given its cardioprotective effect. In this acute setting, however, its effect on the pulse and blood pressure will be counter-productive.
If the bradyarrhythmia and hypotension persist after the administration of atropine, theinsertion of a temporary pacemaker is indicated (choice D). If the patient develops a sick sinus syndrome as a result of the infarct, and is symptomatic in terms of hypotension and syncope, then a pacemaker may be needed.

Cardiac catheterization is indicated in the acute setting (choice E). In this patient, 8
hours have elapsed, and his ST segments have resolved. If he develops another ST
segment elevation myocardial infarction, then he will need an emergent catheterization

Question 19

Q43-While walking home from the hospital, a physician is approached by a man on the street who appears as if he is about to ask a question; however, he suddenly clutches his chest and falls to the ground. The man appears approximately 60 years old and initially appeared diaphoretic and in significant distress. The physician shakes him gently and gives him a sternal rub to determine that he is truly unresponsive. Which of the following is the most appropriate next step in management?

A-Begin chest compressions 
B-Call for help 
C-Check for a pulse 
D-Open patient's airway 
E-Perform two rescue breaths

Answer 19

Ans: B. Time is the most important factor for this patient. Without the appropriate cardiac medications, defibrillator, electrocardiogram, and transport to the closest hospital, this patient will do poorly. Do not waste time getting these resources for your patient. After the call is made, you can continue with your ACLS protocols. Calling for help should always be the first step.

Remember when assessing a patient to always start with the ABCs. The first thing we need to do is open the airway (choice D). This can be done with a jaw-thrust maneuver or a chin lift. After the airway is secured, the patient’s breathing can be assessed by looking, listening, and feeling for air movement. If you determine that there is no air movement, you would then perform two rescue breaths (choice E). The last step is to determine if there is a pulse (choice C). The best place to check for a pulse is the carotid artery. Never check both carotids simultaneously because that can occlude blood flow to the brain. Finally, if there is no pulse, you can begin chest compressions (choice A).
The key learning point in this question is that calling for help is the most important thing you can do in this scenario.

Question 20

Q44-A 25-year-old woman sustains multiple injuries in a car accident, including a pelvic fracture. She is hemodynamically stable. Initial assessment shows no vaginal or rectal injuries; however, when a Foley catheter is inserted, bloody urine is recovered. Which of the following would be the best way to evaluate her urologic injury?

A-Sonogram of the bladder
B-Intravenous pyelogram
C-Cystoscopy
D-Retrograde cystogram including post-void films
E-Retrograde cystogram including views of the ureters

Answer 20

Ans: D. Bloody urine plus pelvic fracture equals bladder injury ineither gender, or bladder or urethral injury in the male. In this case, with the very short and well-protected female urethra not being suspected, only the bladder is the obvious candidate. Injecting dye and taking x-ray films will show the extravasation, but it is important to include post-void films because extravasation at the bladder neck can be obscured by the dye that is filling the bladder.

Sonogram (choice A) is a good, noninvasive way to look at things, but here we can get far better detail with a study (the retrograde cystogram) that is not particularly invasive.
Intravenous pyelogram (choice B) would show dye extravasation, but with far less detail than that provided by direct injection.

Cystoscopy (choice C) would be invasive and not easy to do. When a cystoscopy is
done, fluid is injected into the bladder to expand it and see the walls. In this case, the injected fluid would go out into the peritoneal cavity or the preperitoneal space.

Looking at the ureters (choice E) is not necessary when bladder injury is suspected. The ureters are rarely injured in blunt trauma.

Question 21

Q45-A 36-year-old man always waits for rush hour to go home after work, even though he occasionally finishes his job much earlier. He usually squeezes onto a crowded train and presses his body against a woman. At these times, he usually has erections and sometimes ejaculates. This behavior is most characteristic of which of the following disorders?

A-Dyspareunia
B-Exhibitionism
C-Fetishism
D-Frotteurism
E-Sexual masochism

Answer 21

Ans: D. The disorder belongs to the paraphilias, which are
characterized by deviant or bizarre sexual impulses or practices. Patients repeatedly engage in this behavior and are unable to control their impulses. In frotteurism, sexual arousal is achieved by rubbing the genitals against women, usually in crowded places where a potential victim cannot easily escape. The disorder is more common in nonassertive, passive men.

Dyspareunia (choice A) belongs to the sexual pain disorders and is defined by
persistent genital pain before, during, or after sexual intercourse. The criteria for this disorder exclude vaginismus.

Exhibitionism (choice B) is a paraphilia defined by the need for public exposure of the genitals to evoke shock or fear in victims. Offenders are usually male.

Fetishism (choice C) is a paraphilia defined by the need to use certain inanimate objects to accomplish sexual arousal. It is usually seen in men. The disorder is accompanied by guilt, which is typically addressed in individual psychotherapy.
Sexual masochism (choice E) is a paraphilia in which sexual pleasure is derived from being humiliated or physically or mentally abused by the partner.

Question 22

Q45-A 14-year-old girl comes to the office for a health maintenance evaluation. She is concerned that she has not yet started her menstrual cycle. Her height has increased by 3 inches since her last visit 1 year ago, and her weight is up by 10 pounds. On physical examination, the physician notes a general enlargement of her breasts and areola. Examination of her genital area reveals pubic hair that is coarse and dark and extends past the medial border of the labia.
Which of the following is the most likely diagnosis?

A-Constitutional delay
B-Dysfunctional uterine bleeding
C-Dysmenorrhea
D-Primary amenorrhea
E-Secondary amenorrhea

Answer 22

Ans: A. Constitutional delay is normal pubertal progression at a delayed rate or onset. The average age at menarche is 12 1/2 years, but it may be
delayed until 16 or may begin as early as age 10.

Dysfunctional uterine bleeding (choice B) results when the endometrium has
proliferated under estrogen stimulation, and then begins to slough and causes irregular painless bleeding. This is common in younger adolescents who have not been menstruating long.

Dysmenorrhea (choice C) is pain associated with menstrual cycles, and this adolescent is not menstruating yet.

Primary amenorrhea (choice D) is a delay in menarche with no menstrual cycles or
secondary sex characteristics by 14 years of age or no menses with secondary sex
characteristics by 16 years of age. This adolescent has secondary characteristics but is not yet 16 years of age.

Secondary amenorrhea (choice E) is the absence of menses for at least three cycles
after regular cycles have been present.

Question 23

Q47-A 6-year-old boy with mental retardation has recently been diagnosed with Fragile X syndrome. His 9-year-old sister appears to be of normal intelligence but has symptoms of attention deficit hyperactivity disorder (ADHD). She has no significant medical conditions. What is the first test that is indicated in her work-up for ADHD?

A-EEG
B-Cytogenetic testing
C-MRI
D-Intelligence quotient (IQ) test
E-Urine for metabolic screen

Answer 23

Ans: B. Cytogenetic testing should be performed on all sisters of males with Fragile X. Heterozygous females frequently have developmental and
behavioral problems such as ADHD. They may also have borderline or mild mental retardation.

An EEG (choice A) is likely to be normal, and unless there are signs or symptoms
suggestive of a seizure disorder, it would not be indicated.
ADHD is a clinical diagnosis and no neuroimaging tests such as MRI (choice C) will be useful in making the diagnosis of ADHD.

IQ testing (choice D) may be helpful in school placement, but it is not the first test to be ordered.

Urine for metabolic screening (choice E) is used to detect rare inborn errors of
metabolism. It would be indicated in cases of failure to thrive, seizures, and sepsis. Many inborn errors of metabolism are associated with severe mental retardation.

Question 24

Q48-A 38-year-old white man is brought to the physician by his mother. The mother states that the patient has begun to exhibit “bizarre movements that make him look like he’s impersonating a snake.” He has also become increasingly paranoid and irritable over the last 2 years. He has few friends and has never moved out of the family house that he grew up in. The patient’s father died in an assisted living facility at the age of 45 after having a similar initial presentation. Which of the following is the most likely diagnosis?

A-Amnestic disorder, not otherwise specified
B-Huntington disease
C-Parkinson dementia
D-Senile dementia, Alzheimer type
E-Vascular dementia

Answer 24

Ans: B. Huntington disease is an autosomal dominant disorder that involves degeneration of neurons in the basal ganglia, producing choreoathetoid movements and psychiatric symptoms that may include depression, psychosis, personality changes, and dementia.

The patient does not have cognitive problems limited to memory. The diagnosis of an amnestic disorder (choice A) is therefore inappropriate.
Parkinson dementia (choice C) is characterized by dementing illness in the context of the neuromuscular symptoms that are classic for Parkinson disease (resting tremor, rigidity, bradykinesia). This patient does not present with this history.
Senile dementia, Alzheimer type (choice D) is the most common type of dementia. 
It is usually characterized by onset later in life (older than 65 years of age). Patients with Alzheimer disease do not typically present with choreoathetoid movements and are usually substantially older than this patient.

Vascular dementia (choice E) is a dementing illness occurring from occlusion of small and medium sized vessels in the parenchyma of the brain. It is a dementia that may be stepwise in course, with deficits corresponding to new infarctions. The patient’s presentation and family history is much more suggestive of Huntington disease than of vascular dementia.

Question 25

Q49-A 59-year man comes to his primary care physician with fever and chills. His past medical history is significant for osteoarthritis for many years. He has a long smoking history of greater than 150 pack-years. He routinely takes only a non-steroidal anti-inflammatory agent for pain.
He presents with 5 days of fever and chills associated with a productive cough. He has not been hospitalized recently and lives at home with his wife and has no sick contacts. On physical examination he is comfortable, his temperature is 38.9 C (102 F) and has bibasilar crackles heard best at the left base. Which of the following is the most appropriate next step in diagnosis?

A-Arterial blood gas
B-Chest radiograph
C-Complete blood count
D-Oxygen saturation check
E-Sputum gram stain

Answer 25

Ans: B

Question 26

Q50-A 31-year-old homosexual man comes to the clinic complaining of pain with defecation. He denies any symptoms of diarrhea, abdominal pain, or fevers. Six months earlier, he developed traveler’s diarrhea while vacationing in Mexico. On physical examination, he is afebrile and has an unremarkable abdominal examination. On examination of the perianal area, there is a group of five clustered ulcers adjacent to the anal orifice and extending into the anal canal. A sigmoidoscopy reveals normal rectosigmoid mucosa. Which of the following is the most likely diagnosis?

A-Cytomegalovirus infection
B-Herpes infection
C-Gonorrhea
D-Shigella dysenteriae
E-Ulcerative colitis

Answer 26

Ans: B. This patient is complaining of pain with defecation without any associated abdominal or bowel symptoms. The reference to traveler’s diarrhea is a red herring. The grouped ulcers are characteristic of a herpetic infection. The ulcers begin as vesicular lesions and then painfully ulcerate. The perineal region is frequently involved, and the lesions may spread into the anal canal but do not usually cause any evidence of proctosigmoiditis. These symptoms are often accompanied by neuropathic symptoms, as the herpes resides in the dorsal ganglia.

Cytomegalovirus infection (choice A) may involve the colon in a severely
Immunocompromised HIV patient whose CD4 count is less than 50. This man has no evidence of HIV and furthermore has no colitic symptoms. In addition, cytomegalovirus will not cause ulceration on the exterior perianal skin.

Gonorrhea (choice C) may be the cause of a sexually transmitted proctitis but will
present with a mucopurulent discharge and perhaps symptoms of mild proctitis but
without ulceration.

Shigella dysenteriae (choice D) will present as an invasive type of diarrhea with bloody, mucoid stools and may cause ulceration in the colon or small bowel but does not cause ulcerations in the anal canal or perianal region.

Ulcerative colitis (choice E) would have an abnormal sigmoidoscopic appearance and present with bloody diarrhea. Ulcerations of the perineal region are not characteristic of ulcerative colitis.