Chapter 25: Diseases of Digestive System

Question 1

Streptococcus Mutans:

Answer 1

• Microbe leading to tooth decay.

- Dextran and Lactic acid.

Question 2

Stages of Tooth Decay:

Answer 2

1. Healthy tooth.
2. Begins with streptococcus mutans.
3. Decay in enamel.
4. Decay in dentin, G+ rods are dominant with some filamentous bacteria. Very little S. Mutans left.
5. Decay enters pulp

Question 3

Gingivitis:

Answer 3

Inflammation and infection of the gums.

-Caused by streptococci, actinomycetes, and anaerobic G- bacteria.

Question 4

Periodontitis:

Answer 4

• Bone and tissue supporting the teeth are destroyed.

- Caused by porphyromonas.

Question 5

Acute necrotizing ulcerative gingivitis:

Answer 5

-Caused by prevotella intermedia.

Question 6

Stages of Peridontal Disease:

Answer 6

1. Healthy gingivae
2. Gingivitis
3. Periodontal pockets
4. Periodontitis.
   Characterized by inflammation and degeneration of structures that support the teeth.

Question 7

Dysentery:

Answer 7

Diarrhea with blood or mucus.

Question 8

Gastroenteritis:

Answer 8

Inflammation of the stomach and intestinal mucosa.

Question 9

Staphylococcal Food Poisoning:

Answer 9

Pathogen: Staph aureus
Symptoms: N and V and Diarrhea. 
Intoxication infection: Intoxication enterotoxin. 
Diagnosis: Phage typing
1-6 hour incubation time

Question 10

Shigellosis:

Answer 10

Bacillary Dysentary:
-4 species.
-incubation 12 hours-2 weeks.
-Blood and mucus in stool, abdominal cramps, fever.
-Spread from person to person.
-Ulceration of intestinal mucosa.
Caused by shiga toxin (damages the mucosa) and lipid a (causes fever).

Question 11

Salmonellosis:

Answer 11

• Meat products are susceptible to salmonella.
• Reptiles carry Salmonella.
• Commercial chicken production: raw chicken, eggs, cookie batter, tomatoes.
• Infective dose: 1,000 bacteria.
• Nausea, abdominal pain, diarrhea.
• Mortality is less than one percent.
• Cooking usually kills S. enterica (salmonella microbe).