
Ciguatera
Ciguatera
fish poisoning is endemic wherever coral reef fishes are a food source.
In South Florida, this includes the local coral reef fishing grounds as
well as all of the Caribbean. It is the most frequently reported seafood-related
disease.
Ciguatera results from the eating of reef fish affected with ciguatoxin.
Ciguatoxin originates from a dinoflagellate name Gambierdiscus toxicus
which colonizes coral beds. The toxin first affects the coral-grazing
fish and is then passed up and through the food chain to the piscivorous
fish (i.e., snapper, grouper, amberjack, barracuda) and finally to man.
The toxin is not affected by either cooking or freezing, and the affected
fish, cooked or raw, is not tainted by bacteria in any way. Typically,
the victim states, "It was the best fish I ever tasted." Ciguatera
symptoms were first described in the 1500's by the Spanish explorers to
Cuba and were attributed to the ingestion of a small snail which they
called cigua.
A typical scenario of Ciguatera fish poisoning would include a delicious
family fish dinner at the evening meal, perhaps applauding the successful
fisher person and the culinary skills of the cook. Several hours later
the rather sudden onset of gastrointestinal complaints awakens one after
another of the fish-feasters. Nausea, vomiting, cramping, abdominal pain,
and diarrhea suggest that perhaps the fish was spoiled.
Intense itching, joint and muscle pain, tingling of the lips, burning
or pain when cold liquids are touched or drank will usually bring at least
the more affected victims to the emergency room, later to find most if
not all the others who also enjoyed the fish were variably affected. With
the exception of ice applied to the tongue or fingertips being interpreted
as a burning sensation, there are no clinical signs. There is no diagnostic
laboratory test. Diagnosis rests with the history of ingestion of reef
fish followed by gastrointestinal and bizarre neurological complaints
all within a few hours' time frame.
Some
of the symptoms can recur hours after treatment, suggesting further ciguatoxin
absorption from the gastrointestinal tract; retreatment has been successful
in these cases. Untreated, ciguatera is usually a self-limited disease
lasting one to two months. However, symptoms can persist months to years,
causing great anguish.
Treatment has traditionally been supportive and disappointing. This has
included antihistamines, amitriptyline, calcium gluconate, pyridoxine,
corticosteroids, atropine and vitamin B. Recently ciguatera has been successfully
treated with IV mannitol.4 The usual dose is 1 gram of mannitol per kilogram
victim's body weight infused intravenously either as a 20 percent mannitol
solution or added to .9 NaCl or Ringer's solution. For help with this
treatment, call the Ciguatera Hotline at (305) 361-4619 or (305) 661-0774.
There is currently no test for Ciguatera, thus, avoidance of potentially
toxic fish makes sense. This includes large predatory reef fish (greater
than 5 pound snappers, greater that 10 pound grouper or amberjack or greater
than 2 pound hogfish). Many old timers say that "fish shorter than
your arm means no harm," however, the age and weight of a fish is
more determinative of any possible toxicity then the length. A fish small
enough to fit on your plate is probably safe. Yellowtail snapper and dolphin
(mahi-mahi) are safe fish to eat at any size in the South Florida and
Caribbean areas.
David A. Neblett has handled a number of Ciguatera poisoning cases and
is happy to provide legal assistance relating to this or other maritime
matters.