II. Epidemiology
- Most common reported fish ingestion related Poisoning in U.S.
- Reaction occurs in up to 90% of Ciguatoxin ingestions
- Most common outbreaks
- Florida
- Hawaii
- West Indies
- Puerto Rico
- U.S. Virgin Islands
III. Pathophysiology
- Dinoflagellates (unicellular Protozoa)
- Gambierdiscus toxicus bioaccumulates in carnivorous reef fish
- Reef fish ingestion results in reaction (>500 individual species have been associated)
- Amberjack
- Grouper
- Snapper
- Sturgeon
- King Mackerel
- Barracuda
- Moray eel
- Toxin
- Ciguatoxin is a tasteless, odorless, lipid soluble toxin
- Ciguatoxin is heat stable and acid-stable
- Ciguatoxin may be transferred via Breastmilk and placenta as well as via semen
- Mechanism
IV. Symptoms: Anticholinergic Reaction
- Onset of symptoms at 2 to 6 hours after ingestion (up to 24 hours)
- Gastrointestinal (duration 24-48 hours)
- Nausea or Vomiting
- Voluminous, watery Diarrhea
- Abdominal Pain and cramping
- Neurologic (duration days to weeks)
- Cardiopulmonary changes (duration days to weeks)
- Miscellaneous
- Diaphoresis
- Sensation of loose or painful teeth
- Post-coital symptoms in women (Dysuria, Dyspareunia, Pelvic Pain)
V. Labs
- See Unknown Ingestion
- Serum Electrolytes
- Evaluate for Electrolyte losses (related to Diarrhea)
- Ciguatoxin Testing (ELISA or HPLC)
- Confirms diagnosis, but typically delayed results
- Ciguatera Poisoning is a clinical diagnosis
VI. Diagnostics
- Electrocardiogram (EKG)
VII. Imaging
- As indicated based on presentation and differential diagnosis
VIII. Course
-
Anticholinergic Symptoms within 2-6 hours after ingestion
- Reactions delayed up to 24 hours in some cases
- Symptom duration: 7 to 14 days
- More severe cases with prior Ciguatoxin reactions
- Paresthesias may persist for months
IX. Management
- See Unknown Ingestion
- Consider Activated Charcoal (1 mg/kg)
- Consider if ingestion within prior 1-2 hours and patient alert
- Supportive care
- Antiemetics (e.g. Zofran IV)
- Electrolyte replacement and intravenous hydration as needed
- May require Vasopressors for Hypotension
- May require Unstable Bradycardia management
- Avoid Alcohol
-
Mannitol does not appear effective in shortening course
- Has been used at 1 g/kg over 30-240 min
- Schnorf (2002) Neurology 58:873-80 [PubMed]
- Admission Criteria
- Unclear diagnosis (See Unknown Ingestion)
- Significant neurologic or cardiac symptoms
- Significant Dehydration or Electrolyte abnormalities
X. Complication
- Stocking-Glove distribution neuropathic pain
- Peripheral Neuropathy symptoms may persist for weeks after onset
- Medications to consider
- Amitriptyline 25 mg orally once to twice daily
- Gabapentin 300-400 mg orally three times daily (start with bedtime dosing)
- Pregabalin 150 mg orally twice daily
XI. Prevention
- Avoid ingestion of large warm-water reef fish
- Limit intakes to small quantities
- Avoid ingesting internal organs of fish
- No food preparation method deactivate Ciguatoxin
XII. References
- Koch and Tomaszewski (2021) Crit Dec Emerg Med 35(8): 28
- Perkins (2004) Am Fam Physician 69(4):885-90 [PubMed]