MMID Exam 4 December 8 2003

Question 1 - Single Best Answer

Which of the following is NOT a target of currently used antimycotic (antifungal) antibiotics?

tubulin/microtubules
chitin production
ergosterol biosynthesis
ergosterol present in membranes
nucleic acid biosynthesis

Question 2 - Single Best Answer

Which of the following region/disease relationships (the disease is most often acquired in the region) is not correct?

Coccidioidomycosis - southwest U.S.
blastomycosis - southern U.S.
histoplasmosis - Mississippi River Valley
Cryptococcus - New England
All of the above ARE correct.

Question 3 - Single Best Answer

Which of the following fungi is endogenous to humans and is generally not acquired from the environment?

Candida albicans
Aspergillus
Cryptococcus neoformans
Blastomyces
Histoplasma

Question 4 - Single Best Answer

How is Cryptococcus neoformans UNIQUE among the common fungal pathogens?

It is associated with bird/bat droppings.
It mainly causes disease immunocompromised patients.
It exists only as a yeast.
It lacks a capsule.
It exists only as hyphae in humans.

Question 5 - Single Best Answer

In endemic areas for the relevant pathogen, why would patients about to be treated with steroids have their stool examined for ova and parasites?

Some worms only infect immunocompromised patients.
Steroids can induce hyperinfection by certain worms.
Steroids predispose to candidiasis.
Steroids predispose to malaria.
Blastomycosis is associated with steroid use.

Question 6 - Single Best Answer

The tissue tropism and pathology of aspergillosis can be attributed to which characteristic of the causative organism?

It lives within macrophages.
It only infects diabetics.
It does not elicit an immune response.
It secretes highly degradative and toxic enzymes.
It invades blood vessels.

Question 7 - Single Best Answer

A gardener experiences a cut on his finger while working in his garden. Over the course of several days he experiences raised, painless nodules which move up his arm but stop at the axilla. The most likely causative agent for this disease is:

a worm that normally infects cats and for which humans are an inappropriate host.
a protozoan that ingests red blood cells.
a dimorphic fungus.
a protozoan transmitted by the bite of a mosquito.
a worm with a snail as an intermediate host.

Question 8 - Single Best Answer

An otherwise healthy female takes antibiotics for a severe respiratory tract infection. Two days later she suffers from vaginal itching and erythema. The most likely cause of the vaginal symptoms is:

an allergic reaction to the antibiotics.
a dimorphic fungus which can be present as yeast, hyphae, or pseudohyphae in humans.
a fungus that is exclusively a yeast in humans.
a fungus with right angled braches in its hyphae.
outgrowth of antibiotic-resistant bacteria.

Question 9 - Single Best Answer

For a parasite to generate eosinophilia as a result of infection:

it must be longer than 1 inch.
it must invade host cells.
it must be orally ingested.
it must have an extraluminal stage of infection.
it must be a protozoan.

Question 10 - Single Best Answer

Ascaris infection can be treated with:

metronidazole
trimethoprim
griseofulvin
acyclovir
mebendazole

Question 11 - Single Best Answer

Falciparum malaria is more serious that vivax because:

only falciparum infects liver cells
only falciparum has a significant extracellular stage in the human host
only falciparum can infect any stage of red blood cell development
falciparum does not require a mosquito host
falciparum secretes a more potent toxin

Question 12 - Single Best Answer

A patient has liver abscess evident on CT scan, ulcers in the colon evident on endoscopy, and has dysentery. The most likely causative agent can be diagnosed by:

observing ingested red blood cells in the organism by microscopy
using the string test (enterotest)
observing eggs in the stool
microscopic examination of a blood smear
blood culture

Question 13 - Single Best Answer

When diagnosing pelvic inflammatory disease (PID), it is most important to consider that the infection usually manifests itself with symptoms caused by inflammation of the:

perineum.
peritoneum.
glomeruli.
appendix.
All of the above.

Question 14 - Single Best Answer

All of the following are means by which parasites evade immunity EXCEPT:

antigenic mimicry
shedding antigens from their surface
induction of nonspecific immunoglobulin production
ingestion of lymphocytes
antigenic variation

Question 15 - Single Best Answer

Why do patients infected with ascaris often exhibit respiratory symptoms such as wheezing?

Immune complexes are lodging in the capillaries of the lungs.
Infection with ascaris predisposes to viral respiratory infection.
The worms migrate through the lungs.
Eggs lodge in the capillaries causing effusion.
None of the above - ascaris does not cause respiratory symptoms.

Question 16 - Single Best Answer

Pinworm infection is most often diagnosed by:

observation of worms being coughed up by infected children.
observation of worms passed in the stool.
detection of eggs near the anus.
a skin test.
CT scan of the intestines.

Question 17 - Single Best Answer

Most of the roundworm infections of people in the United States could be eliminated if:

people cooked meats completely.
people would wash fresh vegetables and fruits.
people washed their hands after using the restroom.
human fecal waste was properly disposed of or treated.
Public water supplies were effectively treated and decontaminated.

Question 18 - Single Best Answer

Bowel obstruction is most likely the result from which of the following?

Trichuris
Giardia
Ascaris
Enterobius
Entamoeba

Question 19 - Single Best Answer

What do Giardia lamblia and Entameba histolytica have in common?

They both have extraluminal cycles in humans.
They both cause dysentery-like intestinal symptoms.
They both cause only watery diarrhea similar to traveler's diarrhea.
They both are found only in humans.
They both exist as trophozoites in the intestines and cysts outside the host.

Question 20 - Single Best Answer

Which antibiotic is used to treat both bacteria and protozoans?

mebendazole
metronidazole
ketoconazole
protozole
There are no antibiotics that can treat protozoans and bacteria, since these organisms are so different.

Question 21 - Single Best Answer

Malaria is most easily diagnosed by:

Culture of the parasite.
Skin test (cell-mediated immunity).
Blood test for serology (humoral immunity).
Microscopic examination of a blood smear.
Ultrasound of the liver.

Question 22 - Single Best Answer

A 50 year old diabetic whose blood sugar levels have not been managed for a long time and who is experiencing ketoacidosis notices a dime-sized black lesion below his eye. Two days later the lesion has grown to several inches in diameter of necrotic tissue. Microscopic analysis of a scraping from the lesion most likely would reveal:

filamentous structures with right angled branches
filamentous structures with acute angled branches
yeast cells
protozoal cells that have ingested red blood cells
a cyst filled with larval forms of a tapeworm

Question 23 - Single Best Answer

If you practiced medicine in Los Angeles, which of the following diseases would most likely to be present in a patient returning from overseas travel, as opposed to endemic acquisition in the United States?

Cutaneous larva migrans
Falciparum malaria
Cysticercosis
Echinococcosis
Entamoeba histolytica

Question 24 - Single Best Answer

In treating pelvic inflammatory disease, it is important to keep in mind that:

the major causative agents are resistant to most antibiotics.
antivirals, antibacterials, and antiprotozoals should be used in combination.
the infection is usually polymicrobic with different bacteria.
steroids and antibiotics should be combined since it is an inflammatory process.
the single best antibiotic should be given to prevent antagonism between the antibiotics.

Question 25 - Single Best Answer

How do Toxoplasma gondii-infected humans act differently from uninfected humans?

They are attracted to cat urine.
They lose their nocturnal life style.
They develop an affinity for rats.
Women become warm and outgoing, men become jealous and suspicious.
None of the above - there is no evidence that Toxoplasma gondii infection affects human behavior.

   

  Updated: July 15, 2004