Section 4 GRAM POSITIVE ENDOSPORE FORMING BACILLI

Question 1

What are the gram positive spore forming bacilli?

Answer 1

bacillus and clostridium species

Question 2

How long can bacillus and clostridium species survive in the environment?

Answer 2

Many years b/c they for spores

Question 3

What are the characteristics of Clostridium?

Answer 3

 Anaerobic metabolism
 Gram positive
 Endospore forming rod
 Found in soil and water
 Endospores resistant to heat and chemicals
 Produce a variety of enzymes and toxins

Question 4

What is Clostridium perfringens?

Answer 4

Food poisoning (consumption of living microorganism)
Type A enterotoxin = abdominal cramps/diarrhea begin 8-22 hours after consumption
Type C enterotoxin = causes massive necrosis and bleeding (fatal)

Question 5

Where does the term Pig-bel come from and what does it describe?

Answer 5

Type C food poisoning; Pig-bel from Papua New Guinea- short for pig-belly, attacks after a feast where pork is consumed in large quantities, often fatal in children

Question 6

What is Clostridial myonecrosis?

Answer 6

Gas gangrene

Question 7

What happens with gas gangrene (clostridial myonecrosis)?

Answer 7

-C. perfringens inoculated with trauma into muscle secretes exotoxins that destroy muscle, can also contaminate necrotic tissue in an existing wound o -Release enzymes that ferment carbohydrate and produce gas. As enzymes
degrade muscle a thin blackish-green fluid exudes from the skin.
-Palpation reveals crackling consistency due to pockets of gas- called crepitus

Question 8

What are the treatments for gas gangrene?

Answer 8

Surgical cleansing
Penicillin
Hyperbaric Oxygen (100% oxygen at 2-3x air pressure)

Question 9

What is Clostridium Botulinum?

Answer 9

Food poisoning; (consume toxin produced by microbes)

*7 types that block ACh from nerve terminals = flaccid paralysis

Question 10

Which type(s) of clostridium botulinum are from endospores float in air, land on food, and cause double vision, nausea, vomiting w/in 18-36 hours, and sudden respiratory paralysis/death?

Answer 10

Adult botulism and Wound botulism

Question 11

Which disease has endospores that are in a drumstick shape and are found in soil and animal feces?

Answer 11

Clostridium tetani

Question 12

How high are mortality rates with Clostridium tetani?

Answer 12

1 in 3

*vaccination = very important (booster every 10 years)

Question 13

Which disease shows a severe infection of the colon, often after normal gut flora is eradicated by antibiotics?

Answer 13

Clostridium difficile

Question 14

What does antibiotic resistant C. Difficile produce?

Answer 14

Toxin A= enterotoxin, binds to brush border membranes of the gut
Toxin B= cytotoxin damages gut cells
*characterized by terrible smelling diarrhea, fever, and abdominal pain
**can be fatal

Question 15

What are the 3 characteristics of Bacillus Sp.?

Answer 15

Aerobic metabolism
Gram positive rod
Endospore forming -bamboo-like pattern

Question 16

Why is Bacillus Anthracis unique?

Answer 16

Only bacterium with capsule composed of protein. =Prevents phagocytosis

Question 17

Anthrax is primarily a disease among ??

Answer 17

Herbivores (sheep and cows)

Question 18

What type of anthrax is the most common?

Answer 18

Cutaneous Anthrax (contact w/ infected animal, not human); Endospores enter human via cut and creates painless black lesion with resolves spontaneously
*rarely fatal

Question 19

What type(s) of anthrax are fatal?

Answer 19

GI via ingestion of contaminated meat

Inhalation (only 18 cases reported in 20th century)

Question 20

What is the pathogenesis of Bacilus Cereus?

Answer 20

Food poisoning

• Diarrheal toxin: grow in variety of foods
• Emetic (causing vomiting) toxin: grows in rice/pasta/starchy foods

Question 21

What are the characteristics of Bacillus Cereus?

Answer 21

Gram positive rod
Motile
Forms endospores
Non-encapsulated
Resistant to penicillin
Aerobic metabolism