Deck 25: Microbial Diseases of the Digestive System

Question 1

Which of the following causes an infection of the liver?

A) Shigella
B) Vibrio
C) Escherichia
D) Salmonella
E) Hepatitis A virus

Answer 1

E

Question 2

Poultry products are a likely source of infection by

A) Staphylococcus aureus.
B) Salmonella enterica.
C) Clostridium perfringens.
D) Vibrio cholera.
E) Shigella spp.

Answer 2

B

Question 3

Epidemics of bacterial infections of the digestive system are transmitted by

A) Food.
B) Milk.
C) The respiratory route.
D) Water.
E) All of the above.

Answer 3

D

Question 4

"Rice water stools" are characteristic of

A) Amebic dysentery.
B) Salmonellosis.
C) Bacillary dysentery.
D) Cholera.
E) Tapeworm infestation.

Question 5

A 38- year- old man had onset of fever, chills, nausea, and myalgia. On April 29, he had eaten raw oysters. On May 2, he was admitted to a hospital because of a fever of 39°C and two circular necrotic lesions on the left leg. He had alcoholic liver disease. He was transferred to the ICU; therapy with ciprofloxacin was initiated. On May 4, he died. Which of the following is the most likely etiology?

A) Salmonella
B) Yersinia enterocolitica
C) Cyclospora
D) Bacillus cereus
E) Vibrio vulnificus

Question 6

All of the following statements about salmonellosis are true except

A) It requires a large infective dose.
B) The mortality rate is high.
C) A healthy carrier state exists.
D) It is often associated with poultry products.
E) It is a bacterial infection.

Question 7

Which one of the following is not transmitted by water?

A) Hepatitis A virus
B) Cryptosporidium
C) Trichinella
D) Cyclospora
E) Salmonella

Question 8

Bacterial intoxications differ from bacterial infections of the digestive system in that intoxications

A) Are treated with antibiotics.
B) Are transmitted via water.
C) Are more severe.
D) Are accompanied by fever.
E) Have shorter incubation times.

Question 9

Situation 25.1
Following a county fair, 160 persons complained of gastrointestinal symptoms. Symptoms included diarrhea (84%), abdominal cramps (96%), nausea (84%), vomiting (82%), body aches (50%), fever (60%; median body temperature = 38.3°C); median duration of illness 6 days (range 10 hr to 13 days).

-In Situation 25.1, fecal samples should be cultured for all of the following except

A) Campylobacter.
B) Shigella.
C) Enteropathogenic Escherichia coli.
D) Salmonella.
E) Giardia.

Question 10

Helicobacter can grow in the stomach because it

A) Hides in macrophages.
B) Makes a capsule.
C) Makes HCl.
D) Makes NH₃.
E) None of the above.

Question 11

All of the following are eukaryotes that cause gastroenteritis except

A) Pneumocystis.
B) Entamoeba.
C) Cyclospora.
D) Cryptosporidium.
E) Giardia.

Question 12

All of the following are gram- negative rods that cause gastroenteritis except

A) Escherichia.
B) Salmonella.
C) Shigella.
D) Clostridium.
E) Yersinia.

Question 13

The most common cause of traveler's diarrhea is probably

A) Escherichia coli.
B) Campylobacter jejuni
C) Salmonella enterica.
D) Giardia lamblia.
E) Shigella spp.

Question 14

Which of the following pairs is not correctly matched?

A) Pinworm infestation - humans ingest parasite's eggs
B) Taenia infestation - humans are the definitive host
C) Hookworm infestation - parasite bores through skin
D) Trichinellosis - humans eat larva of parasite
E) Hydatid disease - humans are the definitive host

Question 15

The symptoms of trichinellosis are due to the

A) Growth of larval Trichinella in the large intestine.
B) Encystment of adult Trichinella in muscles.
C) Growth of adult Trichinella in the large intestine.
D) Formation of cysticerci.
E) Encystment of larval Trichinella in muscles.

Question 16

All of the following statements about staphylococcal food poisoning are true except

A) It is characterized by rapid onset and short duration of symptoms.
B) Suspect foods are those not cooked before eating.
C) It can be prevented by boiling foods for 5 minutes before eating.
D) It is treated by replacing water and electrolytes.
E) It can be prevented by refrigeration.

Question 17

Which of the following does not produce a gastrointestinal disease due to an exotoxin?

A) Shigella dysenteriae
B) Staphylococcus aureus
C) Clostridium perfringens
D) Vibrio cholerae
E) Clostridium botulinum

Question 18

Which of the following is diagnosed by the presence of flagellates in the patient's feces?

A) Cholera
B) Trichinellosis
C) Giardiasis
D) Cryptosporidiosis
E) Cyclospora infection

Question 19

Clostridium difficile- associated diarrhea is usually preceded by

A) Improper food storage.
B) Eating contaminated food.
C) Travel to an underdeveloped country.
D) Use of broad- spectrum antibiotics.
E) A blood transfusion.

Question 20

Acute gastroenteritis that occurs after an incubation period of 2 to 3 days is probably caused by

A) Rotavirus
B) Staphylococcus aureus
C) Salmonella
D) Giardia
E) Trichinella

Question 21

All of the following are required for tooth decay except

A) Glucose.
B) Acid- producing bacteria.
C) Sucrose.
D) Capsule- forming bacteria.
E) None of the above.

Question 22

Thorough cooking of food will prevent all of the following except

A) Salmonellosis.
B) Trichinellosis.
C) Staphylococcal food poisoning.
D) Beef tapeworm.
E) All of the above.

Question 23

Feces from a patient with diarrhea lasting for weeks with frequent, watery stools should be examined for

A) Bacillus cereus.
B) Yersinia enterocolitica.
C) Vibrio vulnificus.
D) Salmonella.
E) Cyclospora.

Question 24

Which of the viruses listed meets these criteria? Diagnosed by PCR, incubation of 4- 22 weeks, transmitted by the parenteral route, it is a flavivirus.

A) Hepatitis A virus.
B) Hepatitis B virus.
C) Hepatitis C virus.
D) Hepatitis D virus.
E) Hepatitis E virus.

Question 25

The easiest way to prevent outbreaks of gram- negative gastroenteritis is to

A) Add vinegar and spices to foods.
B) Refrigerate foods.
C) Cook foods thoroughly.
D) Salt foods.
E) All of the above.

Question 26

Which of the following organisms is most likely to be responsible for periodontal disease?

A) Gingivirus
B) Gram- negative cocci
C) Gram- positive cocci
D) Gram- negative rods
E) Gram- positive rods

Question 27

Typhoid fever differs from salmonellosis in that in typhoid fever

A) The symptoms are due to an exotoxin.
B) The symptoms are due to infection of the gallbladder.
C) The classic symptom is diarrhea.
D) Chemotherapy is highly effective.
E) The microorganisms become invasive.

Question 28

Acute gastroenteritis that occurs after an incubation period of 4 to 24 hours is probably caused by

A) Salmonella
B) Giardia
C) Staphylococcus aureus
D) Trichinella
E) Rotavirus

Question 29

Which of the following organisms is likely to be transmitted via contaminated shrimp?

A) Trichinella
B) Clostridium perfringens
C) Giardia
D) Vibrio
E) Staphylococcus aureus

Question 30

Most gastrointestinal infections are treated with

A) Penicillin.
B) Quinacrine.
C) Water and electrolytes.
D) Antitoxin.
E) None of the above.

Question 31

The most common mode of HAV transmission is

A) Blood transfusion.
B) Contamination of food during preparation.
C) Contaminated hypodermic needles.
D) Contamination of food before it reaches a food service establishment.
E) Airborne.

Question 32

With which of the following substrates can Streptococcus mutans make a capsule?

A) Sucrose
B) Mannitol
C) Fructose
D) Glucose
E) All of the above

Question 33

Amoebic dysentery and bacillary dysentery differ in the

A) Etiologic agent.
B) Appearance of the patient's stools.
C) Mode of transmission.
D) All of the above.
E) None of the above.

Question 34

Which of the following is treated with tetracycline?

A) Infectious hepatitis
B) Vibrio parahaemolyticus gastroenteritis
C) Escherichia coli gastroenteritis
D) Trichinellosis
E) Staphylococcal food poisoning

Question 35

Most bacteria associated with the teeth and gums are

A) Facultative anaerobes.
B) Anaerobes.
C) Aerobes.
D) None of the above.

Question 36

Which of the following organisms is likely to be transmitted via contaminated pork?

A) Entamoeba
B) Shigella
C) Trichinella
D) Staphylococcus
E) Salmonella

Question 37

In humans, beef tapeworm infestations are acquired by

A) Ingesting cysticerci in the intermediate host.
B) Ingesting segments of adult tapeworms.
C) Ingesting the eggs of Taenia saginata.
D) Ingesting contaminated water.
E) Ingesting contaminated definitive hosts.

Question 38

Microscopic examination of a patient's fecal culture shows spiral bacteria. The bacteria probably belong to the genus

A) Vibrio.
B) Shigella.
C) Escherichia.
D) Salmonella.
E) Campylobacter.

Question 39

Which of the following diseases of the gastrointestinal system is transmitted by the respiratory route?

A) Staphylococcal enterotoxicosis
B) Bacillary dysentery
C) Mumps
D) Vibrio gastroenteritis
E) Traveler's diarrhea

Question 40

Which of the following feeds on red blood cells?

A) Vibrio parahaemolyticus
B) Giardia lamblia
C) Taenia spp.
D) Entamoeba histolytica
E) Escherichia coli

Question 41

Most of the normal microbiota of the digestive system are found in the

A) Mouth.
B) Large intestine.
C) Small intestine.
D) Stomach.
E) C and D.

Question 42

A vaccine to provide active immunity to serum hepatitis is being prepared from

A) Viruses grown in tissue culture.
B) Pooled gamma globulin.
C) Viruses grown in embryonated eggs.
D) Genetically- modified yeast.
E) None of the above.

Question 43

Which of the following pairs is incorrectly matched?

A) Oysters - Vibrio
B) Eggs - Trichinella
C) Beef - E. coli O157:H7
D) Milk - Campylobacter
E) Delicatessen meats - Listeria