Chapter 1.6 Bacillus And Clostridium

Question 1

What are the general characteristics of bacillus and clostridium?

Answer 1

Gram positive, spore forming rods

Question 2

How do bacillus and clostridium cause disease?

Answer 2

By releasing potent exotoxins

Question 3

What is the difference in oxygen use between Bacillus and Clostridium?

Answer 3

Bacillus is aerobic and Clostridium is anaerobic

*In an air tight Closet

Question 4

What are the 2 pathogenic species of bacillus?

Answer 4

Bacillus anthracis and bacillus cereus

Question 5

What disease is caused by bacillus anthracis?

Answer 5

Anthrax

Question 6

What disease is caused by bacillus cereus?

Answer 6

Gastroenteritis (food poisoning)

Question 7

What is unique about the structure of bacillus anthracis?

Answer 7

It is the only bacterium with a capsule composed of a protein that prevents phagocytosis

Question 8

What group does bacillus anthracis mainly affect?

Answer 8

Herbivores (owns and sheep)

Question 9

How can bacillus anthracis reach humans?

Answer 9

During direct contact with infected animals or soil or when handing infected animal products

Question 10

When is the spore of bacillus anthracis activated?

Answer 10

When it is introduced to the host

Question 11

Why is bacillus anthracis an ideal candidate for biological terrorism and welfare?

Answer 11

Because of it’s small size, stability and 100% lethality of pulmonary anthrax

Question 12

What clinical appearance occurs with a cutaneous anthrax infection of bacillus anthracis?

Answer 12

A painless round black lesion with a rim of edema caused by releases of a potent exotoxin that causes localized tissue necrosis

Question 13

What is a malignant pustule?

Answer 13

Painless round black lesion with a rim of edema caused by bacillus anthracis that an cause death if untreated

Question 14

What is pulmonary anthrax?

Answer 14

When spores are taken up by macrophages in the lungs and transported to mediastinal lymph nodes causing mediastinal hemorrhage

Question 15

What results from mediastinal hemorrhage?

Answer 15

Mediastinal widening and pleural effusion

Question 16

How is gastrointestinal anthrax caused by bacillus anthracis?

Answer 16

Following ingestion of spores where bacillus anthracis matures and replicated in intestine where it releases exotoxins resulting in neurotic lesion in intestine

Question 17

What is most often ingested that is contaminated with spores of bacillus anthracis?

Answer 17

Contaminated meat

Question 18

What is the patient presentation with gastrointestinal anthrax?

Answer 18

Vomiting, abdominal pain, and bloody diarrhea

Question 19

Why does anthrax have such a high mortality rate?

Answer 19

From the release of exotoxin

Question 20

How is bacillus cereus different from bacillus anthracis?

Answer 20

Bacillus cereus is motile, non-encapsulated, and resistant to penicillin

Question 21

How does food poisoning occur from bacillus cereus?

Answer 21

Bacillus cereus deposits and germinates in the food and release enterotoxin

Question 22

What are the 2 enterotoxins that cause food poisoning?

Answer 22

Heat-labile toxin and heat-stable toxin

Question 23

What is the clinical presentation of food poisoning from heat-labile toxin from bacillus cereus?

Answer 23

Nausea, abdominal pain and diarrhea lasting 12-24 hours

Question 24

What is the clinical presentation of food poisoning from heat-stable toxin from bacillus cereus?

Answer 24

Short incubation period followed by severe nausea and vomiting with limited diarrhea

Question 25

What is the affect of antibiotic therapy for bacillus cereus food poisoning?

Answer 25

*Be serious, Dr Goofball-- since the food poisoning is cause by the preformed enterotoxin, the antibiotic therapy will not alter the patient's symptoms

Question 26

What are the general characteristics of Clostridium?

Answer 26

Gram-positive, spore forming rods, and anaerobic

Question 27

What diseases are associated with Clostridium?

Answer 27

Botulism, tetanus, gas gangrene, and psuedomembranous colitis

Question 28

How does clostridium harm humans?

Answer 28

Secreting powerful exotoxins and enzymes

Question 29

What are the mechanism of Clostridium botulinum?

Answer 29

Produces lethal neurotoxin that blocks release of Ah from presynaptic nerve terminals in ANS

Question 30

What is the clinical presentation of clostridium botulinum?

Answer 30

Rapidly fatal food poisoning and flaccid muscle paralysis

Question 31

How is adult botulism transmitted?

Answer 31

Eating smoked fish or home-canned vegetables

Question 32

What is the clinical presentation after ingesting adult botulism?

Answer 32

Initially develop bilateral cranial nerve palsies causing double vision (Diplopia) and difficulty swallowing (dysphagia) Leads to general muscle weakness and respiratory paralysis and death

Question 33

How is infant botulism transmitted?

Answer 33

When infants ingest food contaminated with clostridium botulinum Ex. Fresh honey

Question 34

What is the clinical presentation of infant botulism?

Answer 34

Constipated for 2-3 days Difficulty swallowing and muscle weakness "Floppy" babies

Question 35

What disease does clostridium tetanus cause?

Answer 35

Tetanus

Question 36

What is tetanus?

Answer 36

Disease that follows a puncture wound by a rusty nail or skin trauma by any object contaminated with spores

Question 37

Where are clostridium tetani spores found?

Answer 37

Soil and animal feces

Question 38

How does clostridium tetani survive in humans?

Answer 38

Deposit in a wound any germinates as long as there is localized anaerobic environment (necrotic tissue)

Question 39

What exotoxin is released from clostridium tetani?

Answer 39

Tetanospasmin

Question 40

What is the clinical presentation of clostridium tetany?

Answer 40

Tetany- sustained contraction of skeletal muscle Especially in muscles of the jaw Risks sardonicus- grotesque grinning from facial muscle spasm

Question 41

What is trismus?

Answer 41

Muscle spasms of the jaw muscle | Also called lockjaw

Question 42

What disease is caused by clostridium perfringens

Answer 42

Gas gangrene

Question 43

Where is clostridium perfringens found?

Answer 43

Soil where they mature in anaerobic environment and produce gas

Question 44

What are the 2 classes of infection with clostridium perfringens?

Answer 44

Celllulitis/wound infection | Clostridial myonecrosis

Question 45

What is the clinical presentation of a person with cellulitis/wound infection?

Answer 45

Necrotic skin that is moist, spongy, crackling of the skin from the pockets of gas (crepitus)

Question 46

What is the clinical presentation of someone with clostridial myonecrosis?

Answer 46

Pockets of gas in muscles and subcutaneous tissue | Thin, blackish fluid from skin

Question 47

What bacteria causes psuedomembranous enterocolitis?

Answer 47

Clostridium difficile

Question 48

What are the affects of exotoxins released by clostridium difficile?

Answer 48

Toxin A causes diarrhea | Toxin B is cytotoxic to the colon

Question 49

What is the clinical presentation of someone with clostridium difficile?

Answer 49

Severe diarrhea, abdominal cramping, and fever

Question 50

What shows on the colonoscopy of a person with clostridium difficile?

Answer 50

Red inflamed mucosa Areas of white exudate (psuedomembranes) Necrosis of mucosal surface