Non-invasive Clostridia Flashcards Preview

RUSVM Bacteriology Gram Positives > Non-invasive Clostridia > Flashcards

Flashcards in Non-invasive Clostridia Deck (19)
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1

Two main types of non-invasive clostridia

C. botulinum & C. tetani Botulism & Tetanus

2

Botulism - Disease info

Neuroparalytic intoxication - FLACCID paralysis - 7 protein neurotoxins (A-G, C&D most common)

3

Botulism - Species affected

Ruminants - Horses - Mink - Fowl / Waterfowl

4

Botulism -Toxins

BONT - endopeptidases bind to cholinergic nerve cells, decreases release of ACh

5

Botulism - Reservoir

Dead animals, spores germinate, generate toxin. Ingested by carrion eaters or contaminate the environment

6

Botulism - Pathogenesis

BONT ingested, absorbed into GI --> blood --> NMJ of cholinergic nerves/synapses --> Hydrolyzes "docking protein" --> synapses degenerate leading to flaccid paralysis (death from respiratory failure! Numb diaphragm)

7

Botulism - Clinical signs

Recumbency - Extrusion of tongue - Unable to swallow - Birds have limberneck - Shaker foal syndrome (type B botulinum)

8

When I say Shaker Foal syndrome, you say

Type B botulinum - Clostridium botulinum

9

When I say limberneck in birds, you say

Clostridium botulinum

10

When I say a cow is recumbent with its tongue sticking out and can't swallow, you say..

Clostridium botulinum

11

Tetanus - General Disease info

Neuroparalytic intoxication - CLONIC / TONIC sustained convulsions - SPASTIC paralysis

12

Tetanus - Toxins

TENT=Tetanospasmin - Zinc endopeptidases bind neurons, release GABA & glycine, major inhibitory neurotransmitters. Takes weeks-months to generate. Good vaccine because antigenically uniform

13

Ascending tetanus

Follows retrograde - Intra-axonal transport - dogs & cats because not highly susceptible

14

Descending tetanus

In highly susceptible species (humans & horses) dissemination via vascular channels to remote nerve endings

15

Tetanus Transmission

Inoculation of spores into wound - often puncture wounds, anaerobic

16

Tetanus susceptible species

All mammals - Particularly humans, horses, swine, ruminants. Carvinores less

17

Tetanus clinical signs

Retraction of 3rd eyelid - Ears erect - Teeth grinding - tail stiffness - "Sawhorses"

18

When I say sawhorses, you say...

Tetanus!

19

When I say drumstick bacteria, you say...

Noninvasive clostridia! C. tetani