1. The true statement concerning diagnosis and treatment of infants and children with HIV infection is
A) Serologic testing will identify all cases of HIV in infants.
B) If the mother is infected, in utero transmission of HIV is inevitable.
C) Mucocutaneous candidiasis and progressive encephalopathy are not presenting symptoms of AIDS.
D) All children living in the household of an HIV-infected child should receive oral polio vaccine.
E) After a documented episode of pneumocystis carinii pneumonia, children with AIDS should receive prophylactic trimethoprim/sulfamethoxazole (Bactrim, Septran).
Answer
The mother of a 4-year-old is concerned that her child may have food allergies. He has had multiple episodes of rhinitis, otitis media, and atopic dermatis. There is a significant family history of respiratory allergies in both parents and in an older sister.
Which one of the following would be appropriate to tell her?
A)Most food allergies that develop in infants remain for life.
B)The incidence of food allergies is only about 1% to 2% in older children and adults.
C)Skin testing is the most accurate way of diagnosing food allergies.
D)Because of its dangers, parents should never administer epinephrine to children who develop severe allergic reactions to food.
Answer
The parents of a 6-year-old child bring him to your office for a “second opinion.” He is “sick all the time” and his parents fear “something is wrong with his immunity.”
Of the following observations generated from a thorough history and physical examination, which one would suggest the need for additional laboratory or radiographic studies to assess his immune competence?
A) Six episodes of otitis media in the preceding 10 months
B) Three episodes of impetigo in the preceding 12 months
C) Recent pneumonia secondary to Streptococcus pneumoniae
D) Weight loss and failure to thrive
E) Chronic constipation
Answer
A 7-year-old boy is stung by a wasp on his lower leg. A large local reaction with swelling and redness over most of his calf develops over the next 2 days. There are no systemic symptoms.
True statement concerning this patient includes which of the following?
A)A broad spectrum oral antibiotic should be prescribed.
B)The patient’s reaction to subsequent wasp stings will likely be similar to this one. C)Diphenhydramine (Benadryl) is not indicated.
D)Venom immunotherapy would be effective for preventing large local reactions in the future.
Answer
A 15 year old boy, presented with a 1-month history of yellowing of sclera, colored urine, vomiting, and 2 weeks of altered sensorium and irritability. On exam, neurologic testing shows an intention tremor, resting choreoathetoid movements, and an ataxic gait.
His laboratory investigation revealed, Hct 36.6%; Bilirubin total 60.8 mg%, direct – 41.2 mg%; ALT 637 IU/l, AST 498, Alk Phos 320 IU/l, Sodium 133 mEq/l, Potassium 3.2 mEq/l, Proteins Total 4.3 g%, Albumin 2.5g%; PT –control 13.1 sec, test 24.1 sec, INR 2.88, PTT control 30.4 sec and test 51.1 sec.
The most likely diagnosis is:
A) Asperger’s Disorder
B) Rett’s Disorder
C) Tourette’s Disorder
D) Hepatolenticular degeneration
Answer
A 14-year-old female with a history of psychosis is brought to the Emergency Department for a chief complaint that “it is too painful to swallow her food.” She appears acutely ill.
Vital signs show T 102; P 120; R 16; BP 120/70. HEENT shows significant pharyngeal erythema and bilateral adenopathy. Her CBC reveals a WBC of 1,300 and 10% PMNs
The most likely offender to cause agranulocytosis is:
A) clonazepam
B) clozapine
C) chlorazepate
D) chlordiazepoxide
Answer
A mother brought her 16-year-old daughter into the Emergency Department for evaluation. The
adolescent was sleeping for over 16 hours in her bedroom today. Over the past half week she was
awake all night along with her friends at the clubs. She was hyperactive, paranoid, and acting “onedge”.
In fact, she was hiding in her car late at night, avoiding the demons that she hallucinated
outside. The prior afternoon, her mother found her scrubbing the entire kitchen floor incessantly until all the tiles were spotless.
On physical exam, she is wide-awake and alert. Vital signs are normal. Mental status and
neurological exam shows no abnormalities. Vertical nystagmus is absent. She admits to drug abuse.
The most likely drug is:
A) Crystal methamphetamine
B) 3,4-methylenedioxy-n-methylamphetamine (MDMA)
C) Phencyclidine (PCP)
D) D-lysergic acid diethylamide (LSD)
Answer
A 17-year-old pregnant adolescent at 34 weeks EGA is brought into the Emergency Department by her boyfriend when she started talking about “the angels dancing in her head.” She is starting blankly and calmly at the wall and saliva is seen running down her chin. She is scarcely coherent.
Vital signs show T 37 R 22 BP 155/100 and HR 140. HEENT: mydriasis, (+) horizontal and vertical nystagmus. Neuro exam shows ataxia, muscular rigidity and decreased pain sensitivity during pinprick.
She is most likely intoxicated with which of the following illicit drugs:
A) phencyclidine
B) methamphetamine
C) amyl nitrite
D) cannabis
E) LSD
Answer
An 18-year-old histrionic American art student with a history of major depression traveled to Paris in search of l’amour. On her date with Gaston, she sampled a plate of cheddar, Swiss and blue cheese and downed the fine cuisine with a glass of Chianti wine. Within minutes, the young lady developed a severe headache and unsightly sweat across her brow. She vomited twice on Gaston while clutching her chest. One hour later she was dumped in the Emergency Department for good. On exam, vitals show BP 210/80, HR 120, T 37, RR 20. In general, she appears ill and clutching her head. HEENT: mydriasis and bilaterally symmetrical pupils. The most likely offender of her horrible evening is:
A) paroxitine
B) sertraline
C) tranylcypromine
D) amitriptyline
E) cheesy gastritis
Answer
Which ONE of the following is
NOT a useful effect of acute inflammation:
A.Dilution of toxins
B.Formation of fibrin
C.Phagocytosis
D.Stimulation of immune response
E.Swelling of tissues
Answer
The classical complement system characteristically is triggered by:
A.Properdin
B.The antibody-antigen reaction
C.Cobra venom
D.Endotoxin
E.Lysozyme
Answer
The emigration and accumulation of neutrophilic polymorphonuclear leukocytes in the acute inflammation reaction is primarily the result of:
A.Active hyperemia
B.Hydrostatic pressure
C.Increased microvascular permeability
D.Chemotaxis
E.None of the above
Answer
A 72 year old man is admittted to a hospital after suffering a stroke. His family comes to visit him the next day only to discover that he does ot recognize them. When visited by the team of doctors, the patient seems to recognize voices and sounds,but claims that he has never seen his wife or son before. He seems confused because when they talk to him their voices sound just like theones of his family members. Which of the following is the most likely diagnosis?
A.Anosagnosia
B.Confabulation
C.Conversion disorder.
D.Ganser Syndrome
E.Prosopagnosia.
Answer
Which one of the following is not an arbovirus?
A. Ross River virus
B. Murray Valley encephalitis virus
C. Barmah Forest virus
D. Human papillomavirus
E. Dengue virus
Answer
Amenorrhea in an 18 year old with a milky discharge from the nipples is a most recognised feature of:
a) Addison’s disease
b) HIV
c) Occult carcinoma
d) Hypothyroidism
e) Anorexia nervosa
Answer
An infarct of the the inferior cerebellar peduncle is likely to be secondary to occlusion in the territory of the :
a) the Posterior Cerebral Artery
b) the Basilar Artery
c) The superior cerebellar artery
d) The anterior inferior cerebellar artery
e) The posterior inferior cerebellar artery
Answer
Which of these medications blocks the release of synaptic vesicles from cholinergic nerve terminals?
a) Hemicholinium-3
b) Vesamicol
c) botulinus toxin
d) Alphamethyl-DOPA
e) reserpine
Answer
An infarct causes mild contralateral hemiparesis involving leg more than arm or face with more marked ataxia of the weak limbs . This infarct is likely to be secondary to occlusion in the territory of the :
a) the Posterior Cerebral Artery
b) deep penetrating lacunar artery
c) The superior cerebellar artery
d) The anterior inferior cerebellar artery
e) The posterior inferior cerebellar artery
Answer
A young man with anorexia, nausea, and brown urine is thought to have acute viral hepatitis following hepatitis B infection.Screening serologic studies show that IgM anti-HBV core AB is positive. Which of the following mechanisms is likely to explain the hepatic injury in this patient?
a) Direct injury by viral surface antigen
b) hepatocyte lysis by IgM antibody to viral core antigen
c) obstruction of the microcirculation of the liver by B lymphocytes
d) disruption of the hepatocyte membrane by the hepatitis B virus
e) T lymphocyte-mediated lysis of infected hepatic cells
Answer
An infarct causing spatial disorientation is likely to be secondary to occlusion in the territory of the:
a) the Posterior Cerebral Artery
b) the Basilar Artery
c) The superior cerebellar artery
d) The anterior inferior cerebellar artery
e) The posterior inferior cerebellar artery
Answer
A 68 year old homeless man is admitted to the hospital. He complains of lightning like pains in his legs and belly. He walks with a dramatic marked sway and is visibly uncoordinated. It is very difficult for the intern to get any sort of medical history from him, so he summons the resident. On physical examination, the intern notices that there is a sensory deficit affecting both of his legs. He does not have the ability to detect vibratory sensation. When his big toe is moved, the man guesses the correct orientation about half the time. The intern asks him to stand with his feet together. He comments to the chief resident that 'he does not sway'. The chief resident then asks him to close his eyes, and comments to the intern, 'he sways'. Neither intern nor resident is able to elicit Achilles or patellar reflex. His strength and muscle tone are adequate. What condition should be included in the differential diagnosis?
a) Friedreich's ataxia
b) tabes dorsalis
c) amyotrophic lateral sclerosis
d) cerebellar ataxia
e) polio
Answer
A six year old girl with severe abdominal pain and knee and ankle joint pains is suspected of having Henoch-schonlein syndrome. This would be supported by the presence of
a) subperiosteal thickening
b) joint effusion
c) tight skin
d) papular rash
e) pulsus paradoxus
AnswerTags:
MCQ, Pediatrics, Henoch-Schonlein purpura
An infarct causes sudden headache, confusion and dizziness, followed by a rapid progression through stupor to coma . This infarct is likely to be secondary to occlusion in the territory of the :
a) the Posterior Cerebral Artery
b) the Basilar Artery
c) The superior cerebellar artery
d) The anterior inferior cerebellar artery
e) The posterior inferior cerebellar artery
Answer
Thrombomodulin is most likely to be found in which of these cells in the human body?
a) astrocytes
b) macrophages
c) endothelial
d) stem
e) erythrocytes
Answer
An infarct involves the reticular formation. This infarct is likely to be secondary to occlusion in the territory of the :
a) the Posterior Cerebral Artery
b) the Basilar Artery
c) The superior cerebellar artery
d) The anterior inferior cerebellar artery
e) The posterior inferior cerebellar artery
Answer
A medication that is mainly used for the short-term, emergency treatment of very high blood pressure
a) nitrofuran
b) sulfonamides
c) dopamine antagonists
d) Diazoxide
e) nitrates
Answer
Propranolol a commonly used anti-hypertensive drug is contraindicated in diabetic patients being treated with sulphonylurea drugs. The reason for this is because
a) it increases blood glucose levels
b) it adversely reacts with sulphonylurea drugs
c) it masks hypoglycemia
d) it is ineffective in diabetics
e) the statement is incorrect
Answer
Which marker has been found to be most helpful in identifying patients with sickle cell disease who are at high immediate risk of developing "Acute chest syndrome"?
a) cytokeratin fragments
b) M3 epitope of the tissue polypeptide antigen
c) Secretory phospholipase A2
d) Surfactant protein
e) procollagen I carboxyterminal propeptide
Answer
A drug that may cause pericarditis
a) Sulphonylureas
b) Metformin
c) hydralazine
d) Meglitinides
e) Alpha-glucosidase inhibitor
Answer
Muscarinic Acetylcholine receptors are selectively blocked by :
a) atropine
b) C5
c) muscarine
d) curare and C6
e) nicotine
Answer
A carcinogen known to cause hepatocellular carcinoma
a) aniline dyes
b) Aflatoxins
c) Tamoxifen
d) Hydroquinone
e) asbestos
Answer
In pregnancy, an elevated HbA1c at the time of conception is associated with the floowing complications EXCEPT :
a) great vessels transposition
b) Renal Agenesis
c) Chromosomal Abnormalities
d) Sacral Agenesis
e) open spina bifida
Answer
A one year old male child has multiple symmetrical joint contractures of the upper and lower limbs, most marked in the lower limbs, and distributed distally rather than proximally. His subcutaneous tissues are thick and feel doughy. He is also noted to have clubbing. A likely diagnosis is
a) amyoplasia
b) Ehler-Danlos syndrome
c) congenital indifference to pain
d) Hurler's syndrome
e) Marfan syndrome
Answer
Phenoxybenzamine is best described as :
a) alpha-receptor antagonist
b) anticholinergic
c) muscarinic agonist
d) beta blocker
e) nicotinic antagonist
Answer
A 42 year old female decides to become a mother. During her pregnancy she develops pruritis. Other than the itching, her pregnancy and delivery are uncomplicated. However, even after the birth of her healthy baby boy, the pruritis continues. Two years later she develops jaundice. Her past medical history is unremarkable. On physical examination, she is found to have hepatosplenomegaly. Evaluation has ruled out gallstones. Her laboratory results show an elevated alkaline phosphatase (four times normal) and an elevated bilirubin. She is found to have mitochondrial antibodies. What condition should be included in the differential diagnosis?
a) primary biliary cirrhosis
b) hepatitis B
c) hepatocellular carcinoma
d) Laennec's cirrhosis
e) hepatitis A
Answer
Despite overwhelming evidence and a death certificate, a man's mother refused to believe that her son had been killed in an accident. This is best described as
a) Denial
b) Sublimation
c) Projection
d) Rationalization
e) regression
Answer
Knee effusion in a 25 year old girl just returning from her holiday in Ibiza, presents with conjunctivitis, also noted to have bilateral ankle swelling:
a) Lyme disease
b) Nongonococcal septic arthritis
c) Gonococcal arthritis
d) gout
e) Spontaneous osteonecrosis
Answer
The intramuscular injection of glucagon is known to follow first order kinetics. If 50 percent of the glucagon is absorbed from the intramuscular site in 12 minutes, how long would you expect 75% to be absorbed ?
a) 18 minutes
b) 24 minutes
c) 30 minutes
d) 36 minutes
e) 48 minutes
Answer
A recognised side effect of spironolactone, when utilized to treat hypertension is:
a) hyperkalemia
b) acne
c) hypomagnesemia
d) male pattern baldness
e) bronchospasm
Answer
Monoarthritis in a patient with a recent tick bite is suggestive of
a) Lyme arthritis
b) Nongonococcal septic arthritis
c) Gonococcal arthritis
d) gout
e) Spontaneous osteonecrosis
Answer
The presence of antiphospholipid antibodies is most specific for :
a) polymyositis
b) ankylosing sponylitis
c) SLE
d) CREST sydrome
e) Sjogren's Syndrome
Answer
Phenytoin toxicity is exacerbated by the following enzyme inhibitor:
a) Cimetidine
b) Clobazam
c) Sucralfate
d) Allopurinol
e) Lisinopril
Answer
A Class III antiarrhythmic agent that blocks K+ channels, prolongs action potential duration , and lengthens QT interval.
a) propranolol b) acebutolol c) sotalol d) esmolol e) butorphanol
|
Answer
An infarct causing conduction aphasia is likely to be secondary to occlusion of the :
a) Anterior Choroidal Artery
b) Anterior Cerebral Artery
c) Superior division of the MCA territory
d) Inferior division of the MCA territory
e) stem of the MCA territory
Answer
An infarct causing limited infarction of the lateral aspect of the lateral geniculate body is likely to be secondary to occlusion of the :
a) Anterior Choroidal Artery
b) Anterior Cerebral Artery
c) Superior division of the MCA territory
d) Inferior division of the MCA territory
e) stem of the MCA territory
Answer
A ganglionic blocker used in patients with emergent treatment of aortic dissection is
a) trimetaphan
b) diazoxide
c) phenoxybenzamine
d) reserpine
e) alpha-methyldopa
Answer
Which layers of the lateral geniculate ganglion have monochromatic responses ?
a) 2,3 and 5
b) 1 and 2
c) 2 and 6
d) 1,2 and 5
e) 1,4 and 6
Answer
Which of the following is a Beta-1 selective blocker ?
a) propranolol
b) nadolol
c) pindolol
d) oxprenolol
e) metoprolol
Answer
A young girl is diagnosed with rheumatic fever. All of the following manifestations are recognised as part of the Jones major criteria for diagnosis of rheumatic fever except
a) migratory polyarthritis of large joints
b) carditis
c) erythema marginatum
d) sydenham's chorea
e) elevated serum titers of antibodies to streptolysin O (ASO)
Answer
The most useful medication that may be used in generalized epilepsy of unknown cause that produces more than one type of seizure
a) phenytoin
b) primidone
c) carbamazepine
d) valproic acid
e) Phenobarbital
Answer
A Class Ic antiarrhythmic agent with the most potent sodium channel blocking effect:
a) bretylium
b) amiodarone
c) adenosine
d) flecainide
e) lidocaine
Answer
Which of these medications inhibits the plasma membrane pump for choline ?
a) Hemicholinium-3
b) Vesamicol
c) botulinus toxin
d) Alphamethyl-DOPA
e) reserpine
Answer
Which protein does Thrombomodulin activate in the human body?
a) Protein C
b) Raf proteins
c) G-protein
d) de-oxy hemoglobin
e) Glycogen Phosphorylase
Answer
Nonselective beta blocker possessing quinidine-like membrane stabilizing effects.
a) pindolol
b) acebutolol
c) sotalol
d) esmolol
e) butorphanol
Answer
An 18 year old male works in a company where lunches are often catered. One day, the water at the company facility is not working, but they manage to have the lunch anyway. Two weeks later, he becomes sick. He develops anorexia, nausea, malaise and jaundice. During the course of the next four weeks, seven people who shared in the lunch become ill with similar symptoms. After a few weeks, each of the seven people completely recovers and they replace their caterer. What is a likely diagnosis?
a) primary biliary cirrhosis
b) hepatitis B
c) hepatocellular carcinoma
d) Laennec's cirrhosis
e) hepatitis A
Answer
An infarct involving the superior cerebellar peduncle is likely to be secondary to occlusion in the territory of the :
a) the Posterior Cerebral Artery
b) the Basilar Artery
c) The superior cerebellar artery
d) The anterior inferior cerebellar artery
e) The posterior inferior cerebellar artery
Answer
Antimicrobial agent of choice for the outpatient treatment of infections due to animal bite wound :
a) cefuroxime sodium
b) Amoxicillin/clavulanate potassium
c) Trimethoprim-sulfamethoxazole plus clindamycin phosphate
d) Ampicillin sodium/sulbactam sodium
e) ticarcillin disodium/clavulanate potassium
Answer
A drug is distributed in total body water and has an elimination half-life of 45 minutes. Which one of the following statements is consistant with that observation?
a) The drug is stored in high concentration in fat
b) The rapid rate of disappearance rules out metabolism of the drug by the liver
c) The drug is actively transported into tubular urine
d) The drug cannot be bound to plasma proteins
e) The drug is eliminated only by glomerular filtration
Answer
According to Vaughan Williams Classification of antiarrhythmic Drugs, which class would diltiazem belong to ?
a) class 1A
b) class 1B
c) class 1C
d) class III
e) class IV
Answer
Most common finding in stable chronic myeloid leukaemia?
a) splenomegaly
b) cervical lympadenopathy
c) dullness at the lung bases
d) joint effusions
e) hepatomegaly
Answer
| A 34 year old woman with joint pains is suspected of having rheumatoid arthritis. She is found to be rheumatoid factor positive. A specific feature of rheumatoid arthritis is |
a) subperiosteal thickening
b) marginal articular erosions
c) central articular erosions
d) papular rash
e) pulsus paradoxus
Answer
A 19 yo college student presents to ED after with muscle pain, bruising, and tenseness. He recently ran 2 miles, did pushups and leg presses for crew team tryouts. He did not previously participate in physical activity. He also admits to drinking 10 beers last night and recently had an URI. Which lab value would NOT be expected?
CK 100,000 units/liter
WBC 13,000
K 3.2
Ca 8.6
ALT 490
A mother notes that her eight year old son has mild weight loss and a prolonged low grade fever over about two weeks. On examination he is found to have cervical lymphadenopathy and splenomegaly. The most likely diagnosis is
a) brucellosis
b) infective endocarditis
c) psittacosis
d) typhoid fever
e) infectious mononucleosis
Answer
A 60 year old male patient has just had a renal transplant after chronic renal failure secondary to diabetes. He also has a history of celiac disease. He is receiving cyclosporin A as an immunosuppressive agent to reduce the risks of rejection. Which of the following is the most likely complication of Cyclosporin A in this patient?
a) renal impairment
b) heart failure
c) small bowel lymphoma
d) liver failure
e) cholelithiasis
Answer
Which of the following is false regarding dialysis?
-
Preexisting renal insufficiency does not change recovery
-
Hemodialysis may need to be given daily
-
Hemodialysis is indicated for fluid overload
-
Hemodialysis removes toxins, excess fluids, and electrolytes
Which of the following is false:
Patients can usually recover completely if late complications are avoided
Tea-colored urine is usually first sign
Muscle biopsy needed to determine specific cause of genetic myopathy
Hepatic dysfunction occurs in almost all patients
Which of the following is correct:
-
Genetic etiologies of rhabdomyolysis are usually not discovered until late adulthood
-
A six or more hour delay in diagnosing compartment syndrome can lead to irreversible muscle damage or death
-
DIC usually occurs on the 1st day
-
Elderly patients with rhabdomyolysis can usually be treated as outpatients
Which of the following can be used to help diagnosis rhabdomyolysis?
CK between 100-200 units/liter
Decreased LDH
Serum test positive for myoglobin
Pigmented brown or red serum sample
Which of the following is correct regarding Ca replacement?
Ca replacement is always indicated
Ca replacement only if patient symptomatic since patients can become hypercalcemic in recovery phase
Patients usually become hypocalcemic during recovery phase
Ca binding to PO4 causes hypercalcemia
Which of the following is the causative agent of lymphogranuloma venereum?
A. B.(Rochalimaea) henselae
B. E. chaffeensis
C. C. trachomatis
D. R. rickettsii
E. C. burnetii
Answer
Which one of the following organisms normally inhabits the healthy human oral cavity?
A. M. hominis
B. M. orale
C. M. pneumoniae
D. M. fermentans
E. U. urealyticum
Answer
Which of the following mycoplasmas has been implicated as a cause of nongonococcal urethritis (NGU)?
A. Mycoplasma hominis
B. M. pneumoniae
C. M. fermentans
D. M. mycoides
E. Ureaplasma urealyticum
Answer
A man with chills, fever, and headache is thought to have "atypical" pneumonia. History reveals that he raises chickens and that approximately 2 weeks ago he lost a large number of them to an undiagnosed disease. Which of the following is the most likely diagnosis of this man's condition?
A. Anthrax
B. Q fever
C. Relapsing fever
D. Leptospirosis
E. Ornithosis (psittacosis)
Answer
Which one of the following antibiotics binds to penicillin-binding protein-2 (PBP-2)?
A. Penicillin
B. Amdinocillin
C. Amphotericin
D. Chloramphenicol
E. Trimethoprim
Answer
Which one of the following antibiotics inhibits dihydrofolate reductase?
A. Penicillin
B. Amdinocillin
C. Amphotericin
D. Chloramphenicol
E. Trimethoprim
Answer
Which of the following is a quinolone antibiotic with broad Gram-negative and Gram-positive activity?
A. Piperacillin
B. Cefoperazone
C. Ceftriaxone
D. Ciprofloxacin
E. Imipenem
Answer
DNA from a host sample can be amplified by a process known as the polymerase chain reaction (PCR). Which of the following is required for PCR?
A. Knowledge of the genetic sequence to be amplified
B. An single nucleotide primer
C. An ultracentrifuge
D. A universal probe to detect the amplified product
E. A heat-sensitive DNA polymerase enzyme
Answer
Early attempts at the polymerase chain reaction (PCR) used E. coli DNA polymerase. This was replaced with DNA polymerase from Thermus aquaticus ("Taq" polymerase). Which of the following is the primary advantage in using this enzyme?
A. It is cheaper than E. coli polymerase
B. Specificity is increased because nonspecific hybridization of primers does not occur
C. Use of Taq polymerase results in fewer PCR cycles
D. Use of Taq polymerase enables lower temperatures to be used
E. Upon repeated cycling, Taq polymerase becomes denatured, which causes less interference with the hybridization process
Answer
Certain enzymes catalyze the cross-linking of peptidoglycan, a unique constituent of bacterial cell walls. Which of the following may be a factor in antibiotic resistance, the target of which is cell-wall synthesis?
A. Bactoprenol
B. Reverse transcriptase
C. RNA polymerase
D. DNA gyrase
E. Penicillin-binding proteins (PBPs)
Answer
Reversion of Neisseria gonorrhoeae from a fimbriated (fim 1) to a nonfibriated (fim 2) state would result in which one of the following phenomena?
A. Inability of N. gonorrhoeae to colonize the mucosal epithelium
B. Reversion to a Gram-positive stain
C. Death of the organism
D. Loss of serologic specificity
E. A negative capsule strain
Answer
The formation of adenosine triphosphate (ATP) is essential for the maintenance of life. In mammalian systems, the number of moles of ATP formed per gram atom of oxygen consumed (the P/O ratio) is 3; in bacteria, however, the P/O ratio may be only 1 or 2. Which of the following is the primary reason for the lower P/O ratio in bacteria?
A. Absence of nicotinamide adenine dinucleotide (NAD)
B. Loss of oxidative phosphorylation coupling sites
C. Less dependence on ATP as an energy source
D. Absence of a nonphosphorylative bypass reaction
E. A less-efficient mesosome
AnswerTags:
MCQ, Microbiology, ATP
An aliquot of Escherichia coli is treated with ethylenediaminetetraacetic acid (EDTA). The first wash is analyzed and found to contain alkaline phosphatase, DNase, and penicillinase. Which of the following anatomic areas of the cell is most likely to have been affected by the EDTA?
A. Periplasmic space
B. Mesosomal space
C. Chromosome
D. Plasma membrane
E. Slime layer
Answer
Iron is essential in bacterial metabolism. When bacteria invade the human host they must capture iron in order to survive. Which of the macromolecules listed below is important in bacterial iron metabolism?
A. Transferrin
B. Lactoferrin
C. Ferric oxide
D. Lipopolysaccharide (LPS)
E. Siderophores
Answer
Which of the following bacterial transport methods is energy-independent?
A. Facilitated diffusion
B. Simple diffusion
C. Proton gradient energized active transport
D. Group translocation
E. ATP-dependent active transport
Answer
C. diphtheriae may be difficult to isolate from the nasopharynx without the use of special media. Which of the following is the medium of choice?
A. Sheep blood agar
B. Löffler's medium
C. Thayer-Martin agar
D. Thiosulfate citrate bile salts sucrose medium
E. Löwenstein-Jensen medium
Answer
N. gonorrhoeae is a fastidious pathogen and found in sites often contaminated with normal flora. Which of the following is the best medium for isolation?
A. Sheep blood agar
B. Löffler's medium
C. Thayer-Martin agar
D. Thiosulfate citrate bile salts sucrose medium
E. Löwenstein-Jensen medium
Answer
Which of the following is the antibiotic of choice for Lyme disease?
A. Penicillin
B. Ampicillin
C. Erythromycin
D. Vancomycin
E. Ceftriaxone
Answer
A patient with symptoms of urinary tract infection had a culture taken, which grew 5 × 10^3 E. coli. The laboratory reported it as "insignificant." Which of the following is the most clinically appropriate action?
A. Do no further clinical workup
B. Suggest to the laboratory that low colony counts may reflect infection
C. Determine if fluorescent microscopy is available for the diagnosis of actinomycosis
D. Consider vancomycin as an alternative drug
E. Suggest a repeat antibiotic susceptibility test
Answer
Which of the following is the most effective noninvasive test for the diagnosis of Helicobacter-associated gastric ulcers?
A. Detection of H. pylori antigen in stool
B. Growth of H. pylori from a stomach biopsy
C. Growth of H. pylori in the stool
D. IgM antibodies to H. pylori
E. Culture of stomach contents for H. pylori
Answer
A 2-year-old infant is brought to the emergency room with hemolytic uremic syndrome and thrombocytopenia. Which one of the following bacteria would most likely be isolated from a stool specimen?
A. Shigella
B. Salmonella
C. Aeromonas
D. E. coli 0157:H7
E. Enterobacter
Answer
A 70-year-old female patient was readmitted to a local hospital with fever and chills following cardiac surgery at a major teaching institution. Blood cultures were taken and a Gram-positive coccus grew from the blood cultures within 24 hours. Initial tests indicated that this isolate was resistant to penicillin.Which of the following is the treatment of choice for the isolate?
A. Gentamicin
B. Gentamicin and ampicillin
C. Ciprofloxacin
D. Rifampin
E. No available treatment
Answer
A hyperemic edema of the larynx and epiglottis that rapidly leads to respiratory obstruction in young children is most likely to be caused by which of the following?
A. K. pneumoniae
B. M. pneumoniae
C. Neisseria meningitidis
D. H. influenzae
E. H. hemolyticus
Answer
In people who have sickle cell anemia, osteomyelitis usually is associated with which of the following organisms?
A. Micrococcus
B. Escherichia
C. Pseudomonas
D. Salmonella
E. Streptococcus
Answer
A man who has a penile chancre appears in a hospital's emergency service. The VDRL test is negative. Which of the following is the most appropriate course of action?
A. Send the patient home untreated
B. Repeat the VDRL test in 10 days
C. Perform dark-field microscopy for treponemes
D. Swab the chancre and culture on Thayer-Martin agar
E. Perform a Gram stain on the chancre fluid
Answer
Tags:
MCQ, Microbiology, VDRL, Chancre
Group B streptococcus sepsis in an infant is preventable. Which one of the following procedures is most likely to reduce the incidence of group B streptococcal disease?
A. Intrapartum antibiotic treatment
B. Use of a polysaccharide vaccine
C. Screening of pregnant females in the last trimester
D. Identification of possible high-risk births
E. Screening of pregnant females at the first office visit, usually during the first trimester
Answer
A patient with a peptic ulcer was admitted to the hospital and a gastric biopsy was performed. The tissue was cultured on chocolate agar incubated in a microaerophilic environment at 37°C for 5 to 7 days. At 5 days of incubation, colonies appeared on the plate and were curved, Gram-negative rods, oxidase-positive. Which of the following is the most likely identity of this organism?
A. Campylobacter jejuni
B. Vibrio parahaemolyticus
C. Haemophilus influenzae
D. Helicobacter pylori
E. Campylobacter fetus
Answer
Which of the following is the leading cause of bronchiolitis and community-acquired pneumonia in infants?
A. Measles virus
B. Influenza virus
C. Respiratory syncytial virus
D. Parainfluenza virus
E. Adenovirus
Answer