Part 3 of “Name that Poisonous Beast” is ocean-themed.
Name this poisonous beast!
A)
And it’s floaty colleague:
B)
- A) Barracuda contaminated with Ciguatoxin (from Gambierdiscus toxicus, a dinoflagellate)
- Ciguatera poisoning: activates voltage-dependent sodium channels
- Reef fish (barracuda, amberjack, moray eel, grouper, red snapper, sea bass, spanish mackeral)
- Small fish eat contaminated algae—>big reef fish eat small fish—>ciguatoxin is concentrated
- Tasteless, odorless and heat resistant
- Symptom onset: 15 minutes to 24 hours; generally 6-12 hours
- GI: abd pain, n/v/d, painful defecation (appears first)
- Neuro: perioral paresthesia, temperature dysesthesias, dental pain, pruritis, blurred vision, metallic taste, dysuria (within hours to 3 days, may last months)
- Less common: ataxia, hallucinations, resp paralysis, coma
- CV: bradycardia, hypotension, pulm edema (within 2-5 days)
- Treatment: largely supportive and symptomatic
- Activated charcoal, antihistamines, tylenol/NSAIDs (avoid opiates/barbs)
- Mannitol with IV hydration for neuro sx (reverses opening of sodium channels)
- Consider amitriptyline/gabapentin
- For 6 months after recovery, avoid fish, shellfish, alcohol, nuts, nut oils
- Reef fish (barracuda, amberjack, moray eel, grouper, red snapper, sea bass, spanish mackeral)
- B) Box jellyfish [Cnidaria] (Chironex fleckeri)
- Local effects: painful erythema—>linear urticaria (mins-hours)
- Possible full-thickness necrosis (1-2 weeks)
- Systemic effects: headache, n/v, muscle spasm, fever, syncope
- Severe: resp distress/pulm edema, tachycardia, AKI, MI, cardiac arrest
- Lrukandji syndrome (minor box jellyfish): back/chest/abd pain, n/v, diaphoresis, headache, tachycardia, hypertension, agitation, possible MI/pulm edema
- Prehospital treatment:
- Inactivate nematocytes w/vinegar or acetic acid
- Carefully remove live tentacles (detached tentacles can still envenomate for several hours)
- ED treatment: supportive care: wound care, tetanus, antihistamines, consider topical anesthetics and corticosteroids
- Box jellyfish antivenom if cardiac arrest, hypotension, dysrhythmia, coma, resp distress, dysphagia, dysarthria, severe pain refractory to treatment
- Dose: 1 ampule diluted 1:10 with NS IV; 6 ampules in arrest; IV Mag if unsuccessful
- Box jellyfish antivenom if cardiac arrest, hypotension, dysrhythmia, coma, resp distress, dysphagia, dysarthria, severe pain refractory to treatment
- Lrukandji syndrome tx: nitroglycerin/phentolamine for htn, opiates, benzos; no available antivenom
- Local effects: painful erythema—>linear urticaria (mins-hours)
