Ciguatera poisoning (CP) is a rare condition occurring after the ingestion of presumably edible tropical or subtropical fish. CP is caused by ciguatoxin, a poisonous substance produced by the marine organism Gamabierdiscus toxicus, which will accumulate in the organs of edible fish. Gastric lavage is the method of choice for an efficient cure.
Ciguatera poisoning (CP) occurs after the ingestion of contaminated fish and is the most common non-bacterial fish-related poisoning in the world. Currently, five variations of the causative poisonous agent ciguatoxin are known .
CP presents with a combination of gastrointestinal, neurologic and cardiovascular symptoms. Gastrointestinal symptoms often start within the first day after ingestion and typically last for one to two days. They can range from abdominal pain, nausea, diarrhea and vomiting to a painful defecation process. Neurologic symptoms can show at any time between three hours and three days after the ingestion of contaminated fish and last for weeks or even several months. There are lingual or circumoral paresthesias, painful paresthesias, reversed temperature sensation (i.e. hot objects feel cold and vice versa), dental pain, pruritus, arthralgias, myalgias, ataxia, respiratory paralysis and coma  . Cardiovascular symptoms appear in the acute phase and should wear off within five days after ingestion. Bradycardia, hypotension and pulmonary edema have been reported frequently. Generic symptoms of CP are dysuria, chills, sweating, polymyositis, a metallic taste in the mouth and painful ejaculation .
Both genders and all age groups can acquire CP. The symptoms are usually milder in children and most severe in seniors. Notably, neurologic symptoms may worsen as a consequence of alcohol consumption, physical exercise, dietary changes or sexual intercourse. Ciguatoxin is present in semen and breast milk. Sexual intercourse and breastfeeding can, therefore, transmit CP .
Diagnosis is based on the patient's recent history. Ingestion of fish, in particular in warm coastal regions, is a key criterion to look out for. To date, barracuda, greater amberjack, black grouper, blackfin snapper, cubera snapper, dog snapper, horse-eye jack, hogfish, king mackerel, red grouper and yellowfin grouper have been identified as potential carriers of ciguatoxin. Generally speaking, fish from constantly warm regions preferentially inhabiting coral reefs are most likely to accumulate ciguatoxin  .
A few disorders, some of which are food-related, show similar symptoms to CP and should be taken into consideration for diagnosis. Tetraodon poisoning, Scombroid fish poisoning, and physical urticaria are most likely to be mistaken with CP. Tetraodon poisoning additionally presents with pruritus after ingestion of puffer fish; scombroid fish poisoning is related to bacterial toxin production in insufficiently refrigerated tuna, skipjack, mackerel, bonito, and mahi-mahi. Physical urticaria is a stress-related disorder exhibiting pruritus as well as skin lesions in addition to CP symptoms .
Ciguatoxin has been implicated in a patient's ability to discern between black, gray and white colors. Therefore, it is advisable to carry out a visual contrast sensitivity test .
Since chemists have successfully synthesized monoclonal antibodies for ciguatoxin, it is possible to set up an enzyme-linked immunosorbent assay (ELISA) for the toxin, if a tissue sample of the ingested fish species is available .
Tsumuraya T, Fujii I, Hirama M. Production of monoclonal antibodies for sandwich immunoassay detection of Pacific ciguatoxins. Toxicon. 2010;56(5):797-803.