ODR - Botulism Flashcards
Causative organism
C. botulinum
Spore forming, gram positive anaeorobic rod shapred bacillus
Found in soil, marine sediments, mammal guts
Produces neurotoxins A-H or which A B and E are important
Rare life threatening neuroparalytic syndrome by a neurotoxin
How does it cause effect
Botulinum forms spores, develop toxin producing bacilli.
Toxins target synaptic vesicle receptors in pre-synapse on NMJ
Leads to irreversible failure to release ACh.
Disrupts transmision at NMJ, autnonomic ganglia.
Cranial nerves preferentially affect –> binds to sites of rapid depolarisation
Risk factors for bolutism
ivDU
Crush injury
Consumption of contaminated food stuff (honey, fermented)
Abdo bowel injury –> distribution of flora
Cosmetic bolutinum toxin
Soil ingestion
Reptile exposure
Types of botulism syndromes
Wound - most common. Toxin in wound or abcess from spores. IVDU and skin pop.
Infant - toxin absorbed from intestines of babies colonised to c.bot
Food bourne - ingestion of contaminated food.
Adult intestinal - rare, adult bowel absorbs toxin
Iatrogenic - therapeutic botulism
Inhalational - biological weapons.
Clinical features
Prodrome: n/v/dry mouth abdo distention
Symmetrical descending flaccid paralysis –> neck, shoulders, upper limb, cant hold head
Deep tendon reflexes lost
Sensation INTACT
Cranial nerve palsies –> oculobulbar weakenss. Cornal and gag spared
Autonomic –> urinary retnetion constipation etc
Resp failure
DD of botulism
Motor neuropathy:
GBS
MG
Lambert Eaton
Infection
Polio, Diptheria, Paralytic Rabies
Poison
Organophosphate
Tetrodotoxin
Shellfish poisoning
Investigation
Cranial nerve abnormalities plus symmetrical descending weakness
Culture - food samples, gastric aspirate, stool (if food bourn/infant)
Mouse bioassay identifies toxin in serum, secretion, stoool
Neurophysiology –> normal velocity but redices amplitude
ELISA for botulism in specialist centres
Treatment - specific
Specific:
Trivalent ABE equine anti-toxin EARLY
Neutralises free toxin
Skin testing before as anaphylaxis is common
Infants/allergy - Human derive botulinum Ig.
Treatmetn - supportive
Resp failure - monitor FVC, ETT is <15/kg
Sats, ABGs,
Observe bulbar function
Would debridement and send for culture
Ben pen or metronidazole for wound infection
AMINOGLYCOSIDES POTENTITATE THE EFFECTS
food - gastric lavage, enemas and laxative to remove toxin
Prognosis and long term outcomes
Mortality 3-5%
Increased over 60
Lethargy, weakness, SOB, MH issues
Prognosis poor: need MV, severe weakness, the elderly
