Deck 25: Microbial Diseases of the Digestive System

Question 1

Epidemics related to bacterial infection of the digestive system are typically caused by

A) biological vectors.
B) exposure to contaminated soil.
C) contaminated food and water.
D) unpasteurized milk.
E) the respiratory route.

Answer 1

C

Question 2

Which of the following organisms is likely to be transmitted via undercooked pork and horse?

A) Staphylococcus aureus
B) Trichinella spiralis
C) Shigella spp.
D) Entamoeba histolytica
E) Salmonella enterica

Answer 2

B

Question 3

Dental plaque is an example of

A) a biofilm.
B) gingivitis.
C) tooth enamel.
D) dentin.
E) a pellicle.

Answer 3

A

Question 4

In humans, beef tapeworm infestations are acquired by ingesting

A) water contaminated with Diphyllobothrium latum eggs.
B) cystycerci of Taenia saginata in undercooked meat.
C) cystycerci of Taenia solium in undercooked meat.
D) the eggs of Taenia saginata.
E) segments of Taenia solium tapeworms.

Question 5

Which of the following statements about salmonellosis is FALSE?

A) Severity of disease depends on number of organisms ingested.
B) It is a bacterial infection.
C) The mortality rate is high.
D) It is often associated with poultry products.
E) A healthy carrier state exists.

Question 6

Poultry products are a likely source of infection by

A) Helicobacter pylori.
B) Salmonella enterica.
C) Vibrio cholerae.
D) Clostridium perfringens.
E) Shigella spp.

Question 7

Which of the following is mismatched?

A) pinworm infestation - humans ingest parasite's eggs
B) hydatid disease - humans are the definitive host
C) trichinellosis - humans eat larva of parasite
D) Taenia infestation - humans are the definitive host
E) hookworm infestation - parasite bores through skin

Question 8

The most common cause of traveler's diarrhea is

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

Question 9

Which of the following is directly involved in the initiation of dental caries?

A) lactic acid
B) lysozyme
C) dentin
D) sucrose
E) crevicular fluid

Question 10

All of the following pertain to pinworm infections EXCEPT

A) it is a helminth disease.
B) all family members living with the patient must also be treated.
C) diagnosis is by detecting eggs on transparent tape pressed to the perianal area.
D) transmission is typically by contact with fomites or inhalation of eggs.
E) it is most commonly transmitted by cysts in water.

Question 11

Typhoid fever differs from salmonellosis in that in typhoid fever

A) the microorganisms multiply within macrophages.
B) infection occurs due to ingestion of endospores.
C) the symptoms are due to infection of the gallbladder.
D) the incubation period is much longer.
E) infection is spread only in the feces of domesticated animals.

Question 12

Table 25.1 $\begin{array} { | l | l | } \hline \text { Food } & \text { Relative Risk } \\\hline \text { Black beans } & 0.58 \\\hline \text { Corn soup } & 0.75 \\\hline \text { Jalapeño peppers } & 34.13 \\\hline \text { Roma tomatoes } & 5.40 \\\hline\end{array}$

-The relative risks shown in Table 25.1 were calculated for foods suspected of transmitting Salmonella. Which food is the most likely source of infection?

A) black beans
B) corn soup
C) jalapeño peppers
D) roma tomatoes
E) The answer cannot be determined based on the information provided.

Question 13

In Situation 25.1, fecal samples were found to be negative when cultured. The next step in diagnosing the cause of illness would be

A) to begin antibiotic therapy.
B) muscle biopsy.
C) blood cultures.
D) microscopic examination of fecess for oocysts.
E) microscopic examination of feces for viruses.

Question 14

Which of the following pertains to typhoid fever?

A) Causative microorganism multiplies in patient phagocytes.
B) It is also call bacillary dysentery.
C) Enterotoxin spreads via the blood.
D) It is acquired via ingestion of contaminated meat.
E) It is caused by several different species of Salmonella.

Question 15

All of the following are eukaryotic organisms that cause diarrheal disease EXCEPT

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

Question 16

Which of the following is mismatched?

A) beef - E. coli O157:H7
B) chicken - Campylobacter jejuni
C) eggs - Trichinella spirlais
D) oysters - Vibrio parahaemolyticus
E) custard and cream pies - Staphylococcus aureus

Question 17

What is a Dane particle?

A) the chlorine- resistant virus that causes HAV
B) the infectious virion that causes HBV
C) another name for an HBV surface antigen
D) the filamentous particles that cause HAV
E) the spherical particles found in serum of patients with HBV

Question 18

Disease- causing exotoxins are produced by all of the following organisms EXCEPT

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

Question 19

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

A) staphylococcal enterotoxicosis
B) traveler's diarrhea
C) Vibrio gastroenteritis
D) bacillary dysentery
E) mumps

Question 20

Helicobacter pylori can grow in the stomach because it

A) hides in macrophages.
B) possesses an enzyme that neutralizes HCl.
C) invades epithelial cells.
D) makes HCl.
E) makes a capsule.

Question 21

Which of the following statements about staphylococcal food poisoning is FALSE?

A) It can be prevented by heating foods to 50°C for 15 minutes.
B) It can be prevented by adequate refrigeration of food.
C) It is treated by replacing water and electrolytes.
D) It is caused by ingesting an enterotoxin.
E) It is characterized by rapid onset and short duration of symptoms.

Question 22

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

A) Shigella spp.
B) Campylobacter jejuni.
C) Salmonella typhi.
D) Vibrio cholerae.
E) Escherichia coli.

Question 23

Which of the following helminthic diseases is a common infestation found in the southeastern United States?

A) Taenia saginata
B) Enterobius vermicularis
C) Echinococcus granulosus
D) Trichuris trichiura
E) Ascaris lumbricoides

Question 24

A 38- year- old man had onset of fever, chills, nausea, and myalgia while vacationing on the Gulf of Mexico. On April 29, he had eaten raw oysters and gone wading in the warm coastal waters. 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 a history of alcoholic liver disease. He was transferred to the ICU; therapy with antibiotics was initiated. On May 4, he died. Which of the following is the most likely cause?

A) Salmonella typhi
B) Cyclospora cayetanensis
C) Vibrio vulnificus
D) Bacillus cereus
E) hepatitis C virus

Question 25

Acute gastroenteritis that occurs after an incubation period of two to three days and commonly affects children is probably caused by

A) Giardia.
B) rotavirus.
C) Trichinella.
D) Staphylococcus aureus.
E) Salmonella.

Question 26

"Rice water stools" are characteristic of

A) cholera.
B) salmonellosis.
C) bacillary dysentery.
D) tapeworm infestation.
E) amebic dysentery.

Question 27

Which of the following organisms feeds on red blood cells?

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

Question 28

Clostridium difficile- associated diarrhea is usually preceded by

A) a blood transfusion.
B) extended use of antibiotics.
C) travel to an underdeveloped country.
D) eating contaminated food.
E) improper food storage.

Question 29

The most common mode of HAV transmission is

A) contamination of food before it reaches a food service establishment.
B) airborne.
C) contamination of food during preparation.
D) contaminated hypodermic needles.
E) blood transfusion.

Question 30

Which of the following is included in GALT?

A) salivary glands
B) liver
C) thymus
D) Peyer's patches
E) tonsils

Question 31

Thorough cooking of food will prevent all of the following EXCEPT

A) staphylococcal food poisoning.
B) beef tapeworm.
C) trichinellosis.
D) shigellosis.
E) salmonellosis.

Question 32

Gums bleeding while brushing one's teeth is most commonly associated with

A) gingivitis.
B) cavities.
C) trench mouth.
D) periodontitis.
E) halitosis.

Question 33

Which of the following is mismatched?

A) aflatoxin - liver cancer
B) ergot - gangrene
C) Vibrio enterotoxin - secretion of Cl^- , K⁺, and H₂O
D) Salmonella endotoxin - coagulates blood
E) shiga toxin - tissue destruction

Question 34

Which of the following causes inflammation of the liver?

A) hepatitis A virus
B) Escherichia coli
C) Vibrio cholerae
D) Shigella spp.
E) Salmonella enterica

Question 35

The digestive tract is essentially one long tube. The order of the structures, beginning with the mouth, is

A) pharynx, esophagus, stomach, small intestine, large intestine.
B) esophagus, stomach, pharynx, small intestine, large intestine.
C) esophagus, pharynx, stomach, small intestine, large intestine.
D) pharynx, stomach, esophagus, small intestine, large intestine.
E) pharynx, esophagus, stomach, large intestine, small intestine.

Question 36

Many bacterial infections of the lower digestive tract are treated with

A) water and electrolytes.
B) antitoxin.
C) penicillin.
D) thorough cooking.
E) quinacrine.

Question 37

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

A) are transmitted via contaminated water.
B) have shorter incubation times.
C) are more severe.
D) are treated with antibiotics.
E) are accompanied by high fever.

Question 38

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

A) mouth.
B) stomach.
C) stomach and small intestine.
D) small intestine and large intestine.
E) accessory structures.

Question 39

A vaccine to provide active immunity to HBV is prepared from

A) viruses grown in embryonated eggs.
B) genetically modified yeast.
C) viruses grown in tissue culture.
D) pooled gamma globulin.
E) viral particles in patients.

Question 40

Which of the following correctly lists the stages of tooth decay?

A) plaque accumulation, destruction of enamel, decay in tooth pulp, advancement of decay through enamel, decay in dentin
B) destruction of enamel, advancement of decay through enamel, plaque accumulation, decay in dentin, decay in tooth pulp
C) destruction of enamel, plaque accumulation, advancement of decay through enamel, decay in dentin, decay in tooth pulp
D) decay in dentin, plaque accumulation, destruction of enamel, advancement of decay through enamel, decay in tooth pulp
E) plaque accumulation, destruction of enamel, advancement of decay through enamel, decay in dentin, decay in tooth pulp

Question 41

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

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

Question 42

Dental caries is also known as periodontal disease.

Question 43

Lactic acid, an end product of fructose fermentation, causes breakdown of tooth enamel and, eventually, cavities.

Question 44

Mary made her family's favorite cream of broccoli soup for lunch. Lunch was forgotten when her son suddenly remembered he had a soccer game at noon. The family finally returned several hours later and sat down to eat. Although Mary reheated the soup (which had been left out at room temperature while they were gone), why is this no guarantee that Mary and her family will not become sick due to food poisoning?

Question 45

Approximately 30 percent of the body's immune system is located in the intestinal tract.

Question 46

Aflatoxin poisoning is associated with liver cancer.

Question 47

An outbreak of viral gastroenteritis occurs in a pediatrics ward. Rotavirus is the most likely causative agent.

Question 48

Gastroenteritis due to ingestion of food contaminated with Staphylococcus aureus is due to intoxication by enterotoxins.

Question 49

Aflatoxin is a(n) _ associated with ingestion of contaminated .

A) mycotoxin; peanuts
B) endotoxin; peanuts
C) enterotoxin; rye or other cereal grains
D) mycotoxin; rye or other cereal grains
E) enterotoxin; peanuts

Question 50

Campylobacter gastroenteritis is the leading cause of foodborne illness in the United States.

Question 51

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

A) Salmonella typhi.
B) Yersinia enterocolitica.
C) Clostridium perfringens.
D) Escherichia coli.
E) Shigella spp.

Question 52

All of the following infections can result from drinking contaminated water EXCEPT

A) trichinellosis.
B) Cyclospora infection.
C) cholera.
D) giardiasis.
E) cryptosporidiosis.

Question 53

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

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

Question 54

Bacterial infections, but not intoxications, can cause diarrhea.

Question 55

H. pylori is able to survive the acidic environment of the stomach as a result of adaptations that allow it to increase the pH of the immediate environment.

Question 56

EHEC is a major cause of diarrhea in developing countries and may result in the death of small children.