Deck 25: Microbial Diseases of the Digestive System

Question 1

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

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

Answer 1

B

Question 2

Which of the following organisms is shed in the feces of humans and animals,including beavers,and can contaminate water?

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

Answer 2

A

Question 3

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

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

Answer 3

C

Question 4

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

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

Question 5

Acute gastroenteritis that occurs after an incubation period of two to three days,persists for about a week,and commonly affects children is probably caused by

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

Question 6

In humans,beef tapeworm infestations are acquired by ingesting

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

Question 7

The most common cause of traveler's diarrhea is

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

Question 8

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

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

Question 9

Clostridium difficile-associated diarrhea is usually preceded by

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

Question 10

Which of the following is mismatched?

A)Echinococcus granulosus - most benign of human tapeworm infections
B)Taenia solium - cysticerosis
C)trichinellosis - humans eat larva of parasite in undercooked meat
D)pinworm infestation - humans ingest parasite's eggs
E)hookworm infestation - heavy infections may cause pica

Question 11

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

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

Question 12

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 13

Which of the following statements about salmonellosis is FALSE?

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

Question 14

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

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

Question 15

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

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

Question 16

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

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

Question 17

Poultry products are a likely source of infection by

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

Question 18

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

Question 19

Typhoid fever differs from salmonellosis in that in typhoid fever

A)the microorganisms multiply within macrophages.
B)the organism is only spread in the feces of humans.
C)the incubation period is much shorter.
D)the organism first invades the intestinal mucosa.
E)infection occurs due to ingestion of endospores.

Question 20

Thorough cooking of food will prevent all of the following EXCEPT

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

Question 21

Dental plaque is an example of

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

Question 22

The most common mode of HAV transmission is

A)contamination of food during preparation.
B)respiratory route.
C)blood transfusion.
D)contaminated hypodermic needles.
E)airborne.

Question 23

All of the following pertain to pinworm infections EXCEPT

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

Question 24

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

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

Question 25

Which of the following causes inflammation of the liver?

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

Question 26

Helicobacter pylori can grow in the stomach because it

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

Question 27

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

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

Question 28

Many bacterial infections of the lower digestive tract are treated with

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

Question 29

Which of the following is included in GALT?

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

Question 30

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

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

Question 31

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

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

Question 32

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

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

Question 33

Which of the following pertains to typhoid fever?

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

Question 34

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

Question 35

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

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

Question 36

"Rice water stools" are characteristic of

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

Question 37

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

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

Question 38

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

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

Question 39

A vaccine to provide active immunity to HBV is prepared from

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

Question 40

Which of the following is mismatched?

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

Question 41

Which of the following is mismatched?

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

Question 42

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

Question 43

A young child received a red-eared slider turtle as a birthday gift.Within a week the child was suffering from a severe gastroenteritis that required a visit to urgent care.What is the child likely suffering from?

A)salmonellosis
B)Campylobacter infection
C)shigellosis
D)hepatitis A infection
E)cholera

Question 44

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

Question 45

Table 25.1
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 46

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

Question 47

Which structure or component of the small intestine is important to antimicrobial defense?

A)salivary glands
B)stomach acid
C)Paneth cells
D)gall bladder
E)crevicular fluid

Question 48

Humans infected with Enterobius vermicularis may have hydatid cysts within their lungs or other organs.

Question 49

Aflatoxin poisoning is associated with liver cancer.

Question 50

Which is true of the Mumps virus?

A)It is transmitted by the fecal-oral route.
B)It typically begins with symptoms of gastroenteritis.
C)The portal of entry is the respiratory route.
D)A component vaccine is part of the MMR.
E)Male sterility occurs in 40% of infections.

Question 51

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 52

Bacterial infections,but not intoxications,can cause diarrhea.

Question 53

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

Question 54

Which is NOT true of HBV?

A)1/3 of the world population shows serological evidence of past infection.
B)5% of acute HBV infections progress to chronic infection.
C)Filamentous particles are not infectious.
D)Acute HBV infection may be subclinical.
E)Individuals infected as adults are the most likely to become carriers of the virus.

Question 55

Clostridium perfringens typically causes a self-limiting gastroenteritis.

Question 56

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

Question 57

A rushed homemaker prepared a stew from a large cut of beef but the family only consumed a small portion for dinner.The still-hot large pot was placed in the refrigerator overnight.The next day the stew was warmed for lunch.By the evening the entire family was suffering from varying degrees of diarrhea,abdominal cramping and nausea.You most likely suspect the culprit of this event is

A)Salmonella.
B)H)pylori.
C)Shigella.
D)C)perfringes.
E)B)cereus.

Question 58

Situation 25.1
Following a county fair, 160 persons complained of gastrointestinal symptoms. Symptoms included diarrhea (84 percent), abdominal cramps (96 percent), nausea (84 percent), vomiting (82 percent), body aches (50 percent), fever (60 percent; median body temperature = 38.3°C); median duration of illness 6 days (range 10 hr to 13 days).
In Situation 25.1,fecal samples were found to be negative when cultured.The next step in diagnosing the cause of illness would be 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.

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

Question 59

Situation 25.1
Following a county fair, 160 persons complained of gastrointestinal symptoms. Symptoms included diarrhea (84 percent), abdominal cramps (96 percent), nausea (84 percent), vomiting (82 percent), body aches (50 percent), fever (60 percent; 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)Salmonella enterica.
B)Shigella spp.
C)Campylobacter jejuni.
D)enteropathogenic Escherichia coli.
E)Giardia lamblia.

Question 60

What is a Dane particle?

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

Question 61

Describe the process of periodontal disease.

Question 62

Compare the modes of transmission for hepatitis A,B,and C.

Question 63

Discuss why cholera epidemics are often associated with floods.

Question 64

Thinking of a mumps infection,how do the symptoms involve the GI tract,yet lead to airborne transmission of the disease? Why isn't the disease transmitted by fecal-oral contamination instead?

Question 65

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 66

Multiple pathovars of E.coli are well characterized.Identify four different pathogenic strains and discuss the mechanism of disease for each.