MMID -6300 - Exam 4 - December 9th 2002

Question 1 - Single Best Answer

In the United States, persistent, watery diarrhea in an AIDS patient is most likely caused by:

a curved gram-negative rod that secretes a toxin
a worm that invaded the patient through the feet
a sporozoan parasite with no effective treatment
a protozoan that infects red blood cells
a fungus that forms pseudohyphae

Question 2 - Single Best Answer

All of the following contribute to Falciparum malaria being more severe than other forms EXCEPT:

There can be multiple infection of single red blood cells
The percentage of infected red blood cells is higher
The infected red blood cells adhere to the vascular endothelium
A pigment produced by the organisms causes kidney and nervous system damage
The infection recurs after treatment at a very high rate.

Question 3 - Single Best Answer

It is important to differentiate liver abscess caused by bacteria versus Entamoeba histolytica because:

bacterial abscesses usually require surgical drainage while amoebic abscesses usually respond to drugs
bacterial abscesses can be treated with antibiotics but there is no cure for amoebic abscess
amoebic abscesses have a high association with liver cancer, hence surgery is indicated
amoebic abscess only occurs in immunocompromised patients, hence can serve as a sentinel disease for AIDS
None of the above - both diseases respond to metronidazole, hence can be treated without knowing the causative agent.

Question 4 - Single Best Answer

Useful antifungal agents target each of the following except:

chloroplasts
ergosterol
RNA/DNA
membrane sterols
microtubules

Question 5 - Single Best Answer

A transplant patient on corticosteroids presents with fever, stiff neck, and confusion. A CSF culture fails to grow any bacteria, but an India ink test shows encapsulated organisms. The most likely cause for this disease is:

Streptococcus pneumoniae that has become antibiotic resistant.
Cryptococcus neoformans
Entamoeba histolytica
Yersinia pestis
Candida albicans

Question 6 - Single Best Answer

The most common portal of entry for systemic mycoses is the:

skin
hair
intestinal tract
lungs
wounds

Question 7 - Single Best Answer

Which of the following do inhalation anthrax and pneumonic plague have in common?

They both are highly contagious.
They both are acquired from spores.
They both are endemic to the United States.
They both are highly fatal if untreated.
All of the above.

Question 8 - Single Best Answer

A 20 year old male was camping in New England during the summer. Three weeks after returning to Florida he presents with flu-like symptoms and an erythematous lesion on his leg consisting of concentric circles. If this disease is not treated, which of the following is a likely future event?

The patient could suffer from arthritic disease because of immune responses to the pathogen.
The patient will transmit the disease to his close friends.
The patient's pet dogs and cats will be at risk for acquiring the disease.
The patient could suffer from respiratory distress followed by hepatosplenomegaly and recurring fevers.
None of the above - this is a self-limiting disease.

Question 9 - Single Best Answer

A skin test for reactivity to the hyphal antigen histoplasmin is not a useful diagnostic technique for histoplasmosis in Louisville, KY because:

Delayed hypersensitivity takes at least 2 weeks to develop and, therefore, takes too long to be of use.
The Ohio River Valley is outside the endemic area for histoplasmosis.
Most people in this region have been exposed to Histoplasma capsulatum and have an immune response to histoplasmin.
This particular assay has too many false negative results in this part of the country.
Histoplasma capsulatum grows as a yeast form in patients.

Question 10 - Single Best Answer

Amphotericin B is the mainstay of therapy for many disseminated mycoses. However, it presents difficulties for treatment for all of the following reasons EXCEPT:

Amphotericin must be delivered intravenously.
Amphotericin has nephrotoxic side effects.
Amphotericin binds cholesterol in addition to binding ergosterol.
Amphotericin doses needed to destroy disseminated fungi are often toxic to the patient.
Amphotericin cannot be used in immunocompromised patients.

Question 11 - Single Best Answer

A African-American male that works in a slaughter house in Apex, North Carolina has complained of recurring fevers for several weeks. Today he presents at the E.R. with a fever of 104F and very painful and swollen testicles. His liver and spleen are also enlarged. Blood cultures are negative. A test most likely to reveal the organism causing all of his symptoms would be:

VDRL
Gram stain of urethral swab
bacterial culture of the bone marrow
bacterial culture of the CSF
viral antibody test

Question 12 - Single Best Answer

A child is brought to your office in rural Georgia suffering from a severe headache, fever, and swollen lymph nodes. She also has a rash on her trunk, extremities, palms and soles. She was bitten by a tick last week. Blood cultures and a VDRL are negative. The organism causing her problems is most likely

growing in the vascular endothelium
growing in the spinal fluid
growing in the macrophages
a virus
a spirochete

Question 13 - Single Best Answer

A person diagnosed with plague in this country would most likely

be from the southwest
be from the northeast
have handled wild rabbits
have been bitten by a tick
have been on a camping trip and bathed in a pond

Question 14 - Single Best Answer

What zoonotic disease is most likely to cause a false positive VDRL?

plague
Lyme disease
tularemia
listeria
brucellosis

Question 15 - Single Best Answer

The organism causing Giardiasis is structurally most similar to:

Campylobacter jejuni
Entamoeba histolytica
Borrelia burgdorferi
Trichomonas vaginalis
Coccidioides immitis

Question 16 - Single Best Answer

The symptomology of amoebiasis is most similar to:

Shigellosis
Giardiasis
Malaria
Brucellosis
Cholera

Question 17 - Single Best Answer

Malaria acquired in this country is most likely to be in communities in the proximity of

slaughter houses
sewage treatment plants
zoos
airports
deserts

Question 18 - Single Best Answer

A child who is normally happy and easy-going becomes irritable and inattentive in school. This is the only significant symptom. Which of the following parasites most likely causes this situation?

plasmodium
whipworm
pinworm
ascaris
hookworm

Question 19 - Single Best Answer

The mechanism by which whipworms can cause rectal prolapse is

antibodies, autoimmunity
inflammation, tenesmus
a toxin, apoptosis
intracellular growth, cell death
exoenzymes, digestion of the bowel wall with flask-shaped lesions

Question 20 - Single Best Answer

The association of histoplasmosis with bats is due to:

contamination of the bat fur
mosquito transmission from the bat
growth of the organism in the bats
growth of the organism in the bat excrement
None of the above - histoplasmosis is associated with pigeons, not bats.

Question 21 - Single Best Answer

Coccidioides is most likely found in:

the desert Southwest
the Mississippi River valley
Africa
South America
world-wide (no specific areas)

Question 22 - Single Best Answer

Dr. Joe Spacey suggested that a safer anthrax vaccine could be made from just the capsule, rather than whole cells. This probably would not work because

all antibacterial vaccines must have as at least one component of a toxoid
the capsule is made of a substance not recognized by the immune system
Bacillus anthracis does not have a capsule
polysaccharide vaccines are not effective unless conjugated to a protein
polysaccharide vaccines have the most serious side effects

Question 23 - Single Best Answer

Which of the following pairs of disease/diagnostic procedures is NOT correct?

Giardiasis - string test
Pinworm - "Scotch tape test"
Strongyloides - string test
Amoebiasis - Wright stain of stool (ingested RBCs)
Whipworm - eosinophilia

Question 24 - Single Best Answer

A reason for the geographical limitation of schistosomiasis is the range of the:

mosquito vector.
tick vector.
snail host.
rodent host.
None of the above - there is no geographical limit to schistosomiasis

Question 25 - Single Best Answer

A routine chest X-ray shows a floating fungal ball in a cavitary lesion in an otherwise healthy patient's lung. There is no bleeding. This case requires which of the following actions?

Surgical removal.
Administer antineoplastic drugs.
Administer isoniazid.
Administer high dose Amphotericin B and ketoconazole.
Observation only.

Question 26 - Single Best Answer

Which of the following causes mycotic infections that are best described as endogenous disease processes?

Aspergillus
Candida
Histoplasma
Cryptococcus
Coccidiomycosis

Question 27 - Single Best Answer

When worms that normally infect other animals find themselves in humans (an inappropriate host), which of the following is/are a possible outcome:

Migrating skin lesions from the nematodes.
Large cysts containing numerous immature tapeworms.
Migration of nematodes through deep tissues.
All of the above.
None of the above. In inappropriate hosts, the worms always die without causing any apparent pathology.

Question 28 - Single Best Answer

Which of the following is NOT a typical part of microbial populations associated with pelvic inflammatory disease?

Neisseria gonorrhoeae
Chlamydia trachomatis
mixed normal flora
Candida albicans
All of the above are typically associated with PID

Question 29 - Single Best Answer

The potentially serious complications of Pelvic Inflammatory Disease include each of the following EXCEPT:

chronic pain
infertility
ectopic pregnancy
recurring infection
All of the above ARE complications of PID

Question 30 - Single Best Answer

A diabetic patient in ketoacidosis presents with invasive sinusitis. The most likely causative agent has which morphology?

Right angled branching hyphae
Acute angled branching hyphae
Encapsulated yeast
Encapsulated, gram-negative bacterium
Gram-positive spore forming bacterium

   

  Updated: July 15, 2004