Clostridiia

Question 1

Two Major Bacterial Disease Mechanisms

Answer 1

1. Toxin Mediated
   - no organisms required
   - ex botulism or Staph A. Food poisoning
2. Invasion
   - bacterial tissue invasion
   - overactive inflammation

Question 2

Types of Toxin Mediated Disease

Answer 2

1. Pre-Formed Toxin
   -Bacteria colonize external environment (like food)
   -produce toxins
   -toxins enter person (i.e. Ingestion)
   Example: Botulism
2. Bacterial Invasion
   - ingestion of microorganisms-
   - colonization in gut
   - toxin secreted while organism is in body

Question 3

Clostridium (General Facts)

Answer 3

Obligate Anaerobe

Gram Positive Rods

SPORES

Catalase Negative

Oxidase Negative

Many species

Question 4

Where is C. Tetani Found? And other epi

Answer 4

Found in SOIL

One serological type

Very rare- usually non-immunized ind

60% fatality :0

Question 5

What is Tetanus Toxin and how does it work?

Answer 5

Neurotoxin with A and B subunits

Inhibit release of n.transmitter GLYCINE and GABA

Question 6

What does Tetanus cause?

Answer 6

• > SPASTIC PARALYSIS

- convulsive contractions

Question 7

What are the clinical syndromes of Tetanus?

Answer 7

Violent muscle spasms (predominantly flexor muscles)

If involves respiratory muscles can lead to respiratory failure

Aspiration if pharyngeal muscles involved

Question 8

Tetanus pertinent negatives?

Answer 8

NO FEVER

NO SENSORY DEFICIT

Question 9

How do clinicians diagnose Tetanus?

Answer 9

Mostly clinically

Organisms rarely seen in wound site

Question 10

Treat Tetanus

Answer 10

*Human Tetanus immunoglobulin

Penicillin plus wound cleaning

Question 11

How are we gonna prevent Mr. Tetanus?

Answer 11

Immunize with TOXOID
-3 doses in first 6 months of life

Booster every 10 years

Question 12

Clostridium spore location

Answer 12

Tetani: TERMINAL SPORE (diagnostic)

Botulinum: Subterminal oval spore

Question 13

Botulism epi

Answer 13

Very low incidence

Found in soil

Spores very resistant to heat and chemicals

Can grow in CANNED FOOD

Can infect wounds

Question 14

What is Botulism Toxin?

Answer 14

HEAT LABILE protease
But resists acid

Extremely POTENT

7 types

Question 15

How does Botulism Toxin cause disease?

Answer 15

Absorbed by intestines

Carried via blood to peripheral nerve synapses

Enters NERVE CELLS by receptor mediated endocytosis

BLOCKS ACETYLCHOLINE RELEASE into synapse

Question 16

How does botulism manifest clinically?

Answer 16

18-36 hr incubation

Weakness or FLACCID PARALYSIS

SYMMETRICAL

Dilated pupils, dry throat

May affect respiration

Question 17

What are the Pertinent negatives for botulism?

Answer 17

NO FEVER

NORMAL MENTAL STATUS

NO SENSORY DEFICIT

Question 18

How do we diagnose Botulism?

Answer 18

Clinical

Usually can’t culture (preformed toxin)

Detect toxin in serum

Detect source toxin in food

Question 19

What other disease look like botulism?

Answer 19

Myasthenia Gravis

Gillian Barre Syndrome
-ascending paralysis

Question 20

Prevention

Answer 20

No vaccine

COOK CANNED FOOD

Question 21

What is Infant Botulism?

Answer 21

1-8 months of age

Honey common source

Babies eat bacteria and toxin formed in the gut

Subtle symptoms (constipation, weak head control)

Question 22

How do you treat Botulism?

Answer 22

Early: remove toxin from stomach

ANTITOXIN
-toxin specific, remember there’s different types

Question 23

Clostridium Difficile EPI

Answer 23

Common cause of antibiotic resistant diarrhea

Found in GI tract of some health individuals (esp those in hospital)

Question 24

How does C. Diff cause disease?

Answer 24

When normal flora is suppressed (i.e. Antibiotic therapy)

-> C. Diff able to colonize and grow

Produces exotoxins

Question 25

What are the toxins produced by C. DIff?

Answer 25

Exotoxin A:

• enterotoxin
• binds to gut receptor

EXOTOXIN B:

• cytotoxin
• damages colonic mucosa ->bleeding
• leads to PSEUDOMEMBRANE

Question 26

How does C. Diff manifest?

Answer 26

Diarrhea

Pseudomembrane - Yellow/white plaque

PMN in stool

Blood in stool

Question 27

How do we Diagnose C. Diff?

Answer 27

History of antibiotic use

Exotoxin B in stool

ELISA for toxins

Stool culture doesn’t mean disease

Question 28

How do you treat C. Diff?

Answer 28

Stop offending antibiotics

Treat with METRONIDAZOLE or VANCOUVER

Question 29

What in the world is Clostridium Perfringens?

Answer 29

Causes GAS GANGRENE

Hallmark tissue necrosis

Found in soil and Gi

Question 30

What are the two manifestations of C. Perf?

Answer 30

1. Gas Gangrene
   - Invasive rapidly progressing
   - requires surgery to treat
2. Self limiting diarrhea

Question 31

How does Gas Gangrene happen?

Answer 31

Tissue infection

Anaerobic environment

Toxins necrose tissue

Releases gas (H2 and CO2)

Question 32

What are the important C. Perf toxins?

Answer 32

ALPHA TOXIN - lecithinase
-damages host cell membrane

Collagenase and Hyaluronidase
-break down extracellular protein matrix

Question 33

How does C. Perf poison us through food?

Answer 33

Growth in food

Ingest bacteria

Pre-synthesized enteroxtins released

Question 34

How does Gas Gangrene Manifest?

Answer 34

Dependent on anatomy and location of infection

Cellulitis

necrotizing cellulitis

Necrotizing fasciitis

Question 35

What does C. Perf food poisoning look like?

Answer 35

Ab cramps

Watery diarrhea within 8-24 hours

Question 36

Clinical diagnosis for C. Perf?

Answer 36

Crepitus (from gas)

Discoloration and edema

Special culture

Question 37

How would you treat gangrene?

Answer 37

SURGERY and wound cleaning

Penicillin to kill all that remains

Hyperbaric oxygen if available