Chapter 22

Question 1

Dental Plaque

Answer 1

-begins as biofilm
-bacteria undergo metabolism
-produce acids that can dissolve tooth enamel

Question 2

dental caries

Answer 2

tooth decay

Question 3

gingivitis

Answer 3

inflammation of the gums

Question 4

periodontal disease

Answer 4

-advanced inflammation causing the gums to bleed and pull away from the teeth
-aggregatibacter actinomycetemocomitans and porphyromonas gingivalis

Question 5

thrush

Answer 5

-white coating resembling cottage cheese
-caused by the yeast strain, candida albicans
-common in newborns and patiens taking antibiotics

Question 6

osmotic diarrhea

Answer 6

-intestinal osmolarity is higher than internal of mucosal cells, causing water to leave the cells
-pathogens that prevent nutrient absorption can cause osmotic diarrhea

Question 7

secretory diarrhea

Answer 7

-increased ion secretion causes electrolytes to leave, leading to imbalance and water leaving intestinal cells.
-Pathogens that cause ion secretion cause secretory diarrhea.

Question 8

inflammatory diarrhea

Answer 8

-inflammatory cytokines damage mucosal cells and prevent absorption of nutrients and water. Build up of water.
-Shigella and Salmonella are common causes of inflammatory diarrhea

Question 9

motility-related diarrhea

Answer 9

-food moves too quickly through the intestinal tract and nutrients are not absorbed.
-Often caused by enterotoxins and rotavirus

Question 10

gastritis

Answer 10

inflammation of the stomach lining

Question 11

gastroenteritis

Answer 11

inflammation along the gastrointestinal tract

Question 12

enteritis

Answer 12

inflammation mainly of the small intestine

Question 13

enterocolitis

Answer 13

inflammation of the colon and small intestine

Question 14

colitis

Answer 14

inflammation of the colon

Question 15

hepatitis

Answer 15

-inflammation of the liver
-infection, overconsumption of alcohol, toxic chemicals, autoimmune reactions

Question 16

rotavirus

Answer 16

-fecal-oral route
-nonenveloped, segmented, dsRNA
-enterotoxin that causes hypermotility of the intestinal tract
-vaccine prevents severe disease

Question 17

norovirus

Answer 17

-fecal-oral route
-nonenveloped, positive sense, ssRNA
-causes sudden onset of symptoms; can also cause fever, headache, and malaise
-outbreaks common on cruise ships

Question 18

paramyxovirus

Answer 18

Single-stranded RNA virus
Highly infectious, self-limiting infection
Parotid glands
Shed in saliva
Spread via sneezing and coughing
Causes massive swelling of parotid glands and can cause harm if swelling of testes occurs
Vaccination has eliminated most cases

Question 19

Helicobacter pylori

Answer 19

Gram-negative
Survives acidic nature
Urease
Symptoms
Dyspepsia, upper abdominal pain, bloating, belching, nausea
Treatment
Proton pump inhibitors
Antibiotics

Question 20

Enterotoxigenic E. Coli (ETEC)

Answer 20

Produces labile toxin
Causes secretory, watery diarrhea
No animal reservoirs

Question 21

enteroinvasive E. coli (EIEC)

Answer 21

causes bloody diarrhea similar to that caused by Shigella

Question 22

Enterohemorrhagic E. Coli (EHEC)

Answer 22

Shiga toxin
Causes bloody diarrhea
In severe cases EHEC can lead to hemolytic uremia syndrome and thrombocytopenic purpura-clots in either kidneys or circulatory system (skin hemorrhages)

Question 23

shigellosis

Answer 23

Bloody diarrhea
Also called bacillary dysentery
Similar pathogenesis to EIEC
No animal reservoir, but is transmitted between humans through fecal-oral route via food or water
Symptoms include
Abdominal cramping
Fever
Vomiting
Watery diarrhea

Question 24

Salmonellosis

Answer 24

two major diseases are typhoid fever and enterocolitis

Question 25

typhoid fever

Answer 25

No animal reservoir Associated with food preparation Intermittent fevers and diarrhea for 1‒3 weeks Usually resolves after 3-4 weeks, but sometimes antibiotics

Question 26

enterocolitis

Answer 26

Associated with animal contact Short-term illness lasts 6‒48 hours-nausea, vomiting, diarrhea Not treated with antibiotics unless septicemia

Question 27

yersiniosis

Answer 27

Gastrointestinal disease caused by Y. enterocolitica Y. pseudotuberculosis Gram-negative bacilli Associated with wild and domestic animals Transmitted through food or milk Can grow at refrigerator temperatures Causes general enteritis lasting up to 2 weeks Fever, cramping, sometimes nausea and vomiting, diarrhea Antibiotics not recommended

Question 28

Campylobacter enterocolitis

Answer 28

Gram-negative, corkscrew shape Number one cause of diarrhea worldwide Transmitted through consumption of poorly handled or undercooked meat and unpasteurized milk Immunocompromised patients can experience disseminated disease. Pancreas, gallbladder, heart muscles, or peritoneum Hydration therapy, no antibiotics unless severe Rarely, infection causes an autoimmune disease called Guillain-Barré syndrome (nerve damage)

Question 29

cholera

Answer 29

Vibrio cholerae Gram-negative curved rod with a single flagellum Transmitted via fecal-oral route Contaminated water “Rice water stools” Noninvasive; therefore, does not cause fever or bloody stools

Question 30

cholera toxin

Answer 30

secretory diarrhea-stimulates secretion of electrolyes

Question 31

listeriosis

Answer 31

Listeria monocytogenes Gram-positive, non-spore‒forming coccobacilli Associated with animals and animal products Especially unpasteurized dairy Causes a mild gastroenteritis Immunocompromised patients experience disseminated infection and severe septicemia The bacteria lives inside macrophages to avoid detection by the immune system

Question 32

antibiotic-associated colitis

Answer 32

Clostridium difficile (commonly called C. diff) Gram-positive, endospore-forming Chronic antibiotic Nosocomial infection due to improper cleaning and disinfection coupled with vulnerable populations Toxin production Toxins A, B, and CDT Treatment is often fecal bacterial transplant.

Question 33

staphylococcus food poisoning

Answer 33

Staphylococcus aureus Gram-positive, cocci Symptoms are seen within 2‒6 hours upon ingestion Toxin is heat stable