La ciguatera : de l'étiologie du phénomène au traitement de ses symptômes

Abstract

Ciguatera is the most common food poisoning found in the tropical and subtropical areas, acquired by the consumption of marine products. A lot of work concerning its etiology, its epidemiology and its clinical effects, as well as the discovery of the toxins involved, the description of their transfer, the study of their structure and the analysis of their pharmacological effects, have allowed a better understanding of the ciguateric phenomenon. Ciguatera is known to be due to benthic dinoflagellates belonging to the Gambierdiscus gender, in particular G. toxicus. Under specific conditions, this microalga produces gambier-toxins, toxins which are the precursors of other toxins, the ciguatoxins. However, the factors supporting this production are still poorly known, and the implication of others dinoflagellates, cyanophytes or bacteria have been suspected. In contrast, the fish species responsible for the transmission of ciguatera are globally well identified. The clinical symptoms of the intoxication are now well described. They mainly include digestive, neurological and cardiovascular disorders whose preponderance varies according to the nature of the toxins involved, since toxin structures are different between one ocean and the other. The ciguateric intoxication tends to be exported towards non endemic areas where it is still misdiagnosed. No specific antidote exists to date, and it is only by symptomatic or palliative treatments that ciguatera is currently treated.