Cone shell envenomation

Background

• Also known as cone snails
• Conus genus includes 800 species
• Human fatality rates 15-75%
• Neurotoxin, paralytic venoms with a variety of neuromuscular effects through glutamate, adrenergic, serotonin, and cholinergic pathways

Clinical Features

• Sharp prick to extreme pain
• Envenomation site: numbness, swelling, ischemia, cyanosis
• Systemic: weakness, sweating, visual changes, muscle paralysis, respiratory failure, cardiovascular collapse, coma
• Death can occur in 1-5 hours

Differential Diagnosis

• Anaphylaxis

Marine toxins, envenomations, and bites

• Toxins
  • Ciguatera
  • Scombroid
  • Tetrodotoxin (e.g. pufferfish)
  • Shellfish poisoning
    • Amnesic shellfish poisoning
    • Diarrheal shellfish poisoning
    • Neurotoxic shellfish poisoning
    • Paralytic shellfish poisoning
• Stingers
  • Stingray injury
• Venomous fish
  • Cone shell
  • Lionfish
  • Sea urchins
  • Crown-of-Thorns Starfish
  • Stonefish
  • Other: Catfish, zebrafish, scorpion fish
• Nematocysts
  • Coral reef
  • Fire coral
  • Jellyfish (Cnidaria)
    • Box jellyfish
      • Irukandji syndrome
    • Sea wasp
  • Portuguese man-of-war
  • Sea anemones
  • Seabather's eruption
• Phylum porifera (sponges)
• Bites
  • Alligator and crocodile attacks
  • Octopus bite
  • Shark bite
• Infections
  • Vibrio species in saltwater
  • Aeromonas species in freshwater

Evaluation

Workup

• Due to systemic symptoms CMP, Chest X-ray, EKG are reasonable

Diagnosis

• Clinical history

Management

No antivenom available

• ABC's
• Hot water (40C-50C) may provide pain relief based on anecdotal reports
• Prepare for mechanical ventilation with supportive care
• Most patients will develop a chronic wound at the envenomation site with ulceration that often requires persistent care.

Disposition

• ICU if intubated
• No clear information on length of observation

See Also

• Marine toxins, envenomations, and bites