10. Anaerobes I - Clostridium

Neurotoxic and Histotoxic Clostridium

GI

Anaerobic bacteria are typically present in the ____ tract of mammals.

positive

Gram-(POSITIVE/NEGATIVE) Clostridium spp are spore-forming.

devitalized

Removal of ______________ tissue helps limit the growth of anaerobic bacteria.

abscesses

Anaerobic bacteria cause

* __________
* wound infections
* aspiration pneumonia
* intra-abdominal infections
* enteric infections
* bacteremia
* toxaemia

aspiration

Anaerobic bacteria cause

* abscesses
* wound infections
* _____________ pneumonia
* intra-abdominal infections
* enteric infections
* bacteremia
* toxaemia

abdominal

Anaerobic bacteria cause

* abscesses
* wound infections
* aspiration pneumonia
* intra-_________ infections
* enteric infections
* bacteremia
* toxaemia

enteric

Anaerobic bacteria cause

* abscesses
* wound infections
* aspiration pneumonia
* intra-abdominal infections
* __________ infections
* bacteremia
* toxaemia

bacter

Anaerobic bacteria cause

* abscesses
* wound infections
* aspiration pneumonia
* intra-abdominal infections
* enteric infections
* _______emia
* toxaemia

tox

Anaerobic bacteria cause

* abscesses
* wound infections
* aspiration pneumonia
* intra-abdominal infections
* enteric infections
* bacteremia
* ____aemia

anaerobic

__________ bacteria are typically oral and GI tract associated, spreading by direct extension form mucosal surfaces, causing transient bacteremia and secondary localization. Damaged heart valves are especially susceptible.

oral, GI tract

Anaerobic bacteria are typically ______ and ______ _____ associated, spreading by direct extension form mucosal surfaces, causing transient bacteremia and secondary localization. Damaged heart valves are especially susceptible.

mucosal

Anaerobic bacteria are typically oral and GI tract associated, spreading by direct extension form _________ surfaces, causing transient bacteremia and secondary localization. Damaged heart valves are especially susceptible.

bacteremia, localization

Anaerobic bacteria are typically oral and GI tract associated, spreading by direct extension form mucosal surfaces, causing transient ____________ and secondary ___________. Damaged heart valves are especially susceptible.

heart valves

Anaerobic bacteria are typically oral and GI tract associated, spreading by direct extension form mucosal surfaces, causing transient bacteremia and secondary localization. Damaged ________ ________ are especially susceptible.

endogenous

Anaerobic infections are mostly of __________ origin.

clostridium

Large, gram-positive rods. Anaerobic, quick to multiply, and endospore producing.

motile, flagella

Clostridium spp are _________ by ________ (except C. perfringens).

perfringens

Clostridium spp are motile by flagella (except C. ______________).

soil

Clostridium spp are widespread in

* _______
* GI tract
* feces

GI tract

Clostridium spp are widespread in

* soil
* _____ _____
* feces

feces

Clostridium spp are widespread in

* soil
* GI tract
* ________

epsilon

Clostridium spp are powerful toxin producers. ________ toxin from C. perfringens is one of the most lethal toxins. It is considered a bioterrorism agent.

perfringens

Clostridium spp are powerful toxin producers. Epsilon toxin from C. ___________ is one of the most lethal toxins. It is considered a bioterrorism agent.

bioterrorism

Clostridium spp are powerful toxin producers. Epsilon toxin from C. perfringens is one of the most lethal toxins. It is considered a ___________ agent.

neurotoxic

Clostridial pathogens are characterized as

* ________
* histotoxic
* enteropathogenic and enterotoxaemia-producing

histotoxic

Clostridial pathogens are characterized as

* neurotoxic
* __________
* enteropathogenic and enterotoxaemia-producing

enteropathogenic

Clostridial pathogens are characterized as

* neurotoxic
* histotoxic
* ____________ and enterotoxaemia-producing

enterotoxaemia

Clostridial pathogens are characterized as

* neurotoxic
* histotoxic
* enteropathogenic and _____________-producing

protein toxin

All pathogenic clostridia produce at least one ________ _______ or pathogenic extracellular enzyme.

extracellular enzyme

All pathogenic clostridia produce at least one protein toxin or pathogenic __________ _________.

necrosis

Common predisposing factor for and host response to clostridial infection.

horse, human

Clostridium tetani susceptibility


1. ___________
2. _________
3. other spp

tetanus

Clostridium tetani causes

botulism

Clostridium botulinum causes

blackleg

Clostridium chauvoei causes

Clostridium septicum causes malignant edema (gas gangrene) in cattle and pigs and braxy (abomasitis) in sheep.

malignant edema, braxy

Clostridium septicum causes _________ __________ (gas gangrene) in cattle and pigs and __________ (abomasitis) in sheep.

gas gangrene, abomasitis

Clostridium septicum causes malignant edema (_______ __________) in cattle and pigs and braxy (________) in sheep.

septicum

Clostridium _____________ causes malignant edema (gas gangrene) in cattle and pigs and braxy (abomasitis) in sheep.

chauvoei

Causative agent of blackleg. Clostridium ______________

novyi

Clostridium __________ type A and B causes infectious necrotic hepatitis (black disease) and gas gangrene.

necrotic hepatitis

Clostridium novyi type A and B causes infectious _______ __________ (black disease) and gas gangrene.

gas gangreen

Clostridium novyi type A and B causes infectious necrotic hepatitis (black disease) and ______ _________.

septicum, novyi

Clostridium _____________ is the causal agent of gas gangrene in cattle and pigs, while clostridium ____________ is the causal agent in sheep.

tetanus

Acute, potentially fatal intoxication with neurotoxic clostridia.

spastic, flaccid

Tetanus causes __________ paralysis while botulism causes ________ paralysis

botulism, tetanus

____________ causes flaccid paralysis while __________ causes spastic paralysis.

soil, feces

Clostridium tetani is widespread in __________ and __________.

clostridium tetani

Gram-positive anaerobic drumstick-shaped rods.

terminal

Clostridium tetani produce _____________ endospores

tetanus

___________: pathogenesis

* spores enter damaged tissue
* germinate under anaerobic conditions
* multiplication and production of tetanospasmin and tetanolysin
* tetanospasmin travels via blood and lymphatic system
* tetanospasmin binds to motor neurons and travels along axons to the spinal cord

anaerobic, tetanolysin

Tetanus: pathogenesis

* spores enter damaged tissue
* germinate under ______________ conditions
* multiplication and production of tetanospasmin and ______________
* tetanospasmin travels via blood and lymphatic system
* tetanospasmin binds to motor neurons and travels along axons to the spinal cord

blood, lymphatic

Tetanus: pathogenesis

* spores enter damaged tissue
* germinate under anaerobic conditions
* multiplication and production of tetanospasmin and tetanolysin
* tetanospasmin travels via _______ and _________ system
* tetanospasmin binds to motor neurons and travels along axons to the spinal cord

motor neurons

Tetanus: pathogenesis

* spores enter damaged tissue
* germinate under anaerobic conditions
* multiplication and production of tetanospasmin and tetanolysin
* tetanospasmin travels via blood and lymphatic system
* tetanospasmin binds to _________ ________ and travels along axons to the spinal cord

axons, spinal cord

Tetanus: pathogenesis

* spores enter damaged tissue
* germinate under anaerobic conditions
* multiplication and production of tetanospasmin and tetanolysin
* tetanospasmin travels via blood and lymphatic system
* tetanospasmin binds to motor neurons and travels along ___________ to the __________ ___________

tetanospasmin, tetanolysin

The pathogenesis of tetanus relies on production of two toxins: ____________,__ a neurotoxin, and ___________, which potentiates tissue destruction

irreversible, slow

Binding of tetanospasmin is (REVERSIBLE/IRREVERSIBLE). Recovery is (SLOW/QUICK/IMPOSSIBLE).

new axon terminals

Recovery from tetanus requires generation of

ascending tetanus

___________ ____________: Toxin travels from the regional motor nerve in the limb. Spreads to other parts of the body.

descending tetanus

__________ _________: toxin enters the blood stream, affecting the motor nerve centers in the head and neck before spreading to the limbs.

descending

(ASCENDING/DESCENDING) tetanus occurs in susceptible species.

ascending

(ASCENDING/DESCENDING) tetanus occurs in less susceptible species.

descending

(ASCENDING/DESCENDING) tetanus has a poorer prognoses.

5-10, latent

The tetanus incubation period is typically ______ *(range)* days. ____________ tetanus is the development of clinical signs after the initial wound - site of infection - is healed.

tetanus

___________ - clinical signs

* stiffness
* localized spasms
* altered heart and respiratory rates
* dysphagia

stiffness

Tetanus - clinical signs

* ____________
* “rocking horse” stance
* lock-jaw
* localized spasms
* altered heart and respiratory rates
* dysphagia

spasms

Tetanus - clinical signs

* stiffness
* localized __________
* altered heart and respiratory rates
* dysphagia

heart, respiratory

Tetanus - clinical signs

* stiffness
* localized spasms
* altered _________ and _________ rates
* dysphagia

dysphagia

Tetanus - clinical signs

* stiffness
* localized spasms
* altered heart and respiratory rates
* __________

antitoxin

Tetanus - treatment

* _____________
* first step
* provides quick but short-term protection
* anti-tetanus equine serum
* toxoid
* penicillin
* surgical debridement
* supportive care

equine serum

Tetanus - treatment

* antitoxin
* anti-tetanus _______ ________
* toxoid
* penicillin
* surgical debridement
* supportive care

toxoid

Tetanus - treatment

* antitoxin
* anti-tetanus equine serum
* _________
* inactive vaccine
* penicillin
* surgical debridement
* supportive care

penicillin

Tetanus - treatment

* antitoxin
* anti-tetanus equine serum
* toxoid
* __________
* kills toxin-producing vegetative cells in the lesion
* surgical debridement
* supportive care

debridement

Tetanus - treatment

* antitoxin
* anti-tetanus equine serum
* toxoid
* penicillin
* surgical ______________
* Wound can be flushed with hydrogen
* providing aerobic conditions
* supportive care

supportive care

Tetanus - treatment

* antitoxin
* anti-tetanus equine serum
* toxoid
* penicillin
* surgical debridement
* ________ ________
* reduce external stimuli
* sedatives
* mm relaxants

immunization

Tetanus - control

* toxoid ______________
* all horses
* high susceptibility
* high organism load in intestines and manure
* humans working with farm animals
* post-exposure prophylaxis
* prompt wound management
* aseptic technique - surgery
* proper sterilization of surgical instruments

post-exposure

Tetanus - control

* toxoid immunization
* ________________ prophylaxis
* booster vaccine
* prompt wound management
* aseptic technique - surgery
* proper sterilization of surgical instruments

wound management

Tetanus - control

* toxoid immunization
* post-exposure prophylaxis
* prompt ________ __________
* and rational antimicrobial tx
* aseptic technique - surgery
* proper sterilization of surgical instruments

aseptic technique

Tetanus - control

* toxoid immunization
* post-exposure prophylaxis
* prompt wound management
* ________ ________ - surgery
* proper sterilization of surgical instruments

sterilization

Tetanus - control

* toxoid immunization
* post-exposure prophylaxis
* prompt wound management
* aseptic technique - surgery
* proper ____________ of surgical instruments

true

(TRUE/FALSE) Tetanus is vaccine-preventable.

false

(TRUE/FALSE) Because tetanus is vaccine-preventable, surveillance is no longer necessary.

true

(TRUE/FALSE) Because tetanus is vaccine-preventable, the possibility of failure to vaccinate should be investigated in every case.

botulism

Serious, potentially fatal intoxication by ingestion of pre-formed neurotoxin.

A-G

Clostridium botulinum is a diverse group of neurotoxic clostridia, producing toxin types _________ *(range)*

toxin type

Clostridium botulinum ________ _______ determines species affinity.

reservoir, botulinum

Rotting carcasses, decaying vegetation, and contaminated canned foods can serve as a _____________ for Clostridium _______________

E

Avian botulism, as seen with the mass die-off in the Great Lakes, is caused by botulism toxin type __.

maggots

In the avian botulism cycle, ____________ concentrate the toxin produced in decaying carcasses, increasing likelihood of ducks ingesting large quantities and dying.

third eyelid

Protrusion of the _______ _______ was seen in many of the birds that succumbed to botulism.

intoxication

The most common cause of botulism is ____________

botulism

___________ - pathogenesis

* toxin absorbed from GI tract (intoxication)
* distribution of toxin in bloodstream
* toxin leaves circulatory system at neuromuscular junction
* toxin prevents the fusion of synaptic vesicles of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* flaccid paralysis
* death

intoxication

Botulism - pathogenesis

* toxin absorbed from GI tract (__________)
* distribution of toxin in bloodstream
* toxin leaves circulatory system at neuromuscular junction
* toxin prevents the fusion of synaptic vesicles of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* flaccid paralysis
* death

bloodstream

Botulism - pathogenesis

* toxin absorbed from GI tract (intoxication)
* distribution of toxin in ___________
* toxin leaves circulatory system at neuromuscular junction
* toxin prevents the fusion of synaptic vesicles of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* flaccid paralysis
* death

neuromuscular junction

Botulism - pathogenesis

* toxin absorbed from GI tract (intoxication)
* distribution of toxin in bloodstream
* toxin leaves circulatory system at __________ ___________
* toxin prevents the fusion of synaptic vesicles of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* flaccid paralysis
* death

fusion, synaptic vesicles

Botulism - pathogenesis

* toxin absorbed from GI tract (intoxication)
* distribution of toxin in bloodstream
* toxin leaves circulatory system at neuromuscular junction
* toxin prevents the _______ of________ _________ of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* flaccid paralysis
* death

Botulism - pathogenesis

* toxin absorbed from GI tract (intoxication)
* distribution of toxin in bloodstream
* toxin leaves circulatory system at neuromuscular junction
* toxin prevents the fusion of synaptic vesicles of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* flaccid paralysis
* death

flaccid

Botulism - pathogenesis

* toxin absorbed from GI tract (intoxication)
* distribution of toxin in bloodstream
* toxin leaves circulatory system at neuromuscular junction
* toxin prevents the fusion of synaptic vesicles of acetylcholine, and thus prevents the release of acetylcholine at neuromuscular junction
* ___________ paralysis
* death

light, heavy chain

The botulinum toxin has two biochemically important components - a ________ and a _________ _________

irreversible

Binding of the botulinum toxin is (REVERSIBLE/IRREVERSIBLE)