Gram Pos anaerobic rods

Question 1

what are the spore forming + non spore forming gram pos anaerobic rods (1 + 2)

Answer 1

Spore- Clostridium

Non-spore- Propionibacterium spp, Actinomyces spp.

Question 2

are clostridium spp mobile and what are the 4 human pathogens in this species

Answer 2

Motile by peritrichous flagella

1. C. botulinum
2. C. difficile
3. C. perfringens
4. C. Tetani

Question 3

C. botulinum pathogenesis of flaccid paralysis

Answer 3

Enters bloodstream and reaches cholinergic synapses

@ synapse toxins prevent the release of Ach by disrupting SNARE

leads to flaccid parralysis

Question 4

What are the symptoms of bottulism (what is seen first) + how many hours is symptom onset

Answer 4

Symetrical descending weakness starting @ head (CN 3,4,6 first)

• atrophy
• flaccid paraylsis
• parasympathetic dysfucntion

12-36h after ingestion

Question 5

What are the 2 types of botulism + what are they due to

Answer 5

1. Infant botulism- consumption of raw, unpasturized honey

2. Wound botulism- spores contaminate wound, germinate and toxins enter bloodstream

Question 6

What is the route of transmission of clostridium difficile + where is it usually found + why would it spread in you

Answer 6

Oral-fecal route of transmission

typically colonizes the large intestines
-survives amd proliferates when someone is on antibiotics

Question 7

What strains of responsible for pathogenesis of c. difficile and what does it induce

Answer 7

Toxin c diff A or B

induces cytokine secretetion which leads to inflammation in the gut

Question 8

Symptoms of c difficile (2 major concerns)

Answer 8

• Pseudomembranous colitis

- Toxic megacomon (distension; may cause sepsis

Question 9

what are risk factors of c. diff infection(4) + what is main tx

Answer 9

1. antibiotic/ pro pump inhibitors (lowers ph)
2. Hospitilaization
3. Chronic health probs
4. Older age

stopping antibiotics

Question 10

What are the 2 major diseases that clostridium perfringens can cause and toxins they each produce

Answer 10

1. Food poisoning due to C. perfringens enterotoxin (CPE)

2. Gas gangrene due to C. perfringens a toxin

Question 11

What is the pathogenesis of gas gangre caused by clostridum perfringes

Answer 11

• necrotic cell death – visible necrosis (gangrene)
• Large blackened sores with distinctive crepitus caused by gas escaping the necrotic tissue
• can lead to sepsis

Question 12

what does clostridium tetani cause, what is the exotoxin that causes it and what is it due to

Answer 12

• causes tetanus
• exotoxin called tetanospasmin
• tetanus associated with punctures, laceration and Iv drug use

Question 13

What is the pathogenesis of tetanus

Answer 13

Tetanospasm enters nervous system and degrades synaptobrevin which allows release of GABA (inhibitory NT)

Causes muscular ridgitity + spasms

Question 14

What is the clinical presentation of Tetanus

Answer 14

1. Risus Sardonicus (lockjaw)
2. Spasms
3. can cause fx, respiratory failure etc

Question 15

What is the major form of propionibacterium spp and is it spore forming

Answer 15

Non spore forming

-cutibacterium acnes

Question 16

What is cutibacterium acnes associated w/ in the musculoskeletal system

Answer 16

Associated with herniated disks

The propionic acid which it secretes may create micro-fractures in surrounding bone.

Question 17

Actinomyces- spore forming?, what does it cause clinically

Answer 17

Non spoe forming

• Causes oral abscesses associated with dental procedures/ periodontal diseases