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Botulism
Aka: Botulism, Clostridium botulinum, C. botulinum, Botulinum toxin
- See Also
- Infant Botulism
- Biological Neurotoxin
- Etiology
- Clostridium botulinum
- Pathophysiology: Toxin mediated disease
- Botulinum toxins A, B and E are pathogenic in humans
- Botulinum toxin binds to presynaptic nerve terminal
- Neuromuscular terminal
- Cholinergic autonomic site
- Receptor binding is irreversible
- Receptors are replaced however over time
- Affects neuromuscular junction only
- Prevents presynaptic acetylcholine release
- Results in bulbar palsy and skeletal Muscle Weakness
- Does not cause sensory deficit or pain
- Botulinum toxin medical uses (Botox)
- Treatment for oculomotor disorders
- Strabismus
- Blepharospasm
- Treatment for Dystonias
- Torticollis
- Hemifacial spasm
- Transmission
- Aerosol spread as warfare Biological Toxin
- Wound infection
- Associated with trauma and heroin use
- Course differs from Foodborne Illness
- Longer incubation period: 4 to 14 days
- Minimal gastrointestinal symptoms
- Foodborne Illness (ingestion of bacteria or toxin)
- Toxin types A and B in the United States
- West of the Mississippi: Type A toxins
- East of the Mississippi: Type B toxins
- See Infant Botulism (e.g. honey ingestion)
- Improperly preserved canned foods (e.g. tomatoes)
- In-ground vegetables (potatoes, onions, Garlic)
- Meat products in Europe (Toxin Type B)
- Vegetable products in China (Toxin Type A)
- Preserved fish (Toxin type E)
- Found in Alaska, Japan, Russia, Scandinavia
- Symptoms
- Sudden onset symptoms
- Symptoms follow ingestion or exposure by 1-5 days
- Descending symmetric paralysis
- Early changes: Cranial Nerves affected first
- Diplopia with blurred vision (90%)
- Dysphagia (76%)
- Dysarthria
- Dysphonia (55%)
- Later changes
- Generalized Weakness (58%)
- Associated symptoms
- Nausea or Vomiting (56%)
- Dizziness
- Headache
- Abdominal Pain or cramping
- Diarrhea or Constipation
- Anticholingergic symptoms may also be present
- Signs
- Early signs
- Bilateral Cranial Nerve 6 (Abducens Nerve) paralysis
- Mydriasis with sluggish pupil reaction
- Nystagmus
- Ptosis
- Diminished Gag Reflex
- Swollen Tongue
- Later signs
- Symmetrical descending flaccid paralysis
- Hyporeflexia
- Incoordination
- Irregular respirations to respiratory failure
- Distinguishing features from other causes
- Mentation clear
- Patient is usually afebrile
- Neurologic changes are bilateral and descending
- Differential Diagnosis
- Myasthenia Gravis
- Guillain Barre Syndrome
- Eaton-Lambert Syndrome
- Trichinosis
- Cerebrovascular Accident
- Electrolyte disturbance
- Hypocalcemia
- Hypermagnesemia
- Tick Paralysis or Tick Toxicosis (ascending paralysis)
- Other toxin exposure
- Organophosphate Poisoning
- AtropinePoisoning
- Shellfish Poisoning or puffer fish Poisoning
- Labs
- Patient sources
- Serum for Botulinum toxin (positive in 1/3 of cases)
- Gastric contents for Botulinum toxin
- Stool for Botulinum toxin (positive in 1/3 of cases)
- Stool for culture (positive in 60% of cases)
- Wound culture (if present) for organisms
- Test suspected food source for toxin
- Classic testing
- Lab mice die after ingesting suspected food source
- Illness reversed by type specific antitoxin
- Diagnostic testing: Electromyogram (EMG)
- Protocol
- Initial supramaximal single nerve stimulation
- Repetitive stimulation at 40 to 50 hz
- Differentiates from other neuromuscular conditions
- Single maximal stimulus: Diminished action potentials
- Repetitive stimuli: Facilitation of action potentials
- Hypermagnesemia may give similar EMG
- Management: General
- Contact Centers for Disease Control for suspected cases
- Supportive care
- Ventilator support often required
- Antibiotic use only recommended in wound Botulism
- Gastric Decontamination if very recent ingestion
- Management: Antitoxin (from CDC)
- Skin Test for Horse Serum Sensitivity first
- May shorten disease course if used early
- Trivalent equine antitoxin
- Risk of Serum Sickness and Anaphylaxis
- Depreciated Heptavalent equine antitoxin
- Covers types A, B, C, D, E, F, G
- Reduced risk of Serum Sickness
- Effective if given prior to or early in symptoms
- Prevention
- Avoid honey in infants under 1 year of age
- See Infant Botulism
- DOD Pentavalent toxoid vaccine
- Covers types A, B, C, D, E
- Dose: 0.5 SC at 0, 2, and 12 weeks, then annually
- Protective Antibody >90% after 1 year
- Prognosis
- Untreated: Mortality 60% from respiratory failure
- Treated with intensive support: Mortality <7%
- References
- Bartlett in Goldman (2000) Cecil Medicine, p. 1673-4
- Schechter in Behrman (2000) Nelson Pediatrics, p. 875-8
- Shearer in Marx (2002) Rosen's Emergency Med, p. 1525
- Arnon (2001) JAMA 285:1059-70
- Resources
- CDC Disease Information
- http://www.cdc.gov/ncidod/dbmd/diseaseinfo