Ciguatera

Background

  • Caused by eating fish contaminated with a heat-stable toxin, which is obtained when the fish consumes dinoflagellates that grow on and around coral reefs
  • Most cases occur in the tropics and subtropics, between 35 degrees north and south latitudes
  • Most common fish include barracuda, moray eel, amberjack, and certain types of grouper, mackerel, parrotfish, and red snapper
  • Suspected cases should be reported to local department of health
  • Neurologic symptoms typically resolve within days to weeks
    • Persist for months in 20%, and years in up to 2%

Clinical Features

Differential Diagnosis

Marine toxins, envenomations, and bites

Evaluation

  • Clinical diagnosis

Management

  • Symptomatic therapies are the mainstay of treatment
  • Mannitol - Recommended by several experts for neurologic symptoms if given within 24-48 hours of onset [1]. However, no benefit over normal saline in RCT[2]
    • Caution: patients may be hypovolemic due to vomiting/diarrhea and should be appropriately volume resuscitated prior to considering mannitol
  • Amitriptyline reported effective for neuropathic pain in several case series[3] [4]
  • Gabapentin[5] and Pregabalin [6] also reported to control neurologic symptoms
  • Prevent recurrences - instruct patient to not ingest alcohol, caffeine, nuts or fish for 6 months

Disposition

  • Generally may be discharged
  • Advise caution that patients should avoid consumption of similar fish for six months as it could trigger a recurrence.

See Also

References

  1. Friedman MA et al. Ciguatera Fish Poisoning: Treatment, Prevention, and Management. Marine Drugs 2008; 6:456-479
  2. Schnorf H et al. Ciguatera Fish Poisoning. A double-blind randomized trial of mannitol therapy. Neurology 2002; 58(6):873
  3. Lange W et al. Travel and ciguatera fish poisoning. Arch. Int. Med. 1992; 152:2049-2052
  4. Davis RT and Villar LA. Symptomatic improvement with amitriptyline in ciguatera fish poisoning. N Engl J Med 1986; 315:65
  5. Perez CM et al. Treatment of ciguatera poisoning with gabapentin. N Engl J Med 2001; 344:692
  6. Brett J and Murnion B. Pregabalin to treat ciguatera fish poisoning. Clinical toxicology 2015; 53(6):588.