tetrodotoxin and Ciguatera-Poisoning

Tetrodotoxin (TTX) is a crystalline, weakly basic, colorless organic substance and is one of the most potent marine toxins known. Although TTX was first isolated from pufferfish, it has been found in numerous other marine organisms and a few terrestrial species. Moreover, tetrodotoxication is still an important health problem today, as TTX has no known antidote. TTX poisonings were most commonly reported from Japan, Thailand, and China, but today the risk of TTX poisoning is spreading around the world. Recent studies have shown that TTX-containing fish are being found in other regions of the Pacific and in the Indian Ocean, as well as the Mediterranean Sea. This review aims to summarize pertinent information available to date on the structure, origin, distribution, mechanism of action of TTX and analytical methods used for the detection of TTX, as well as on TTX-containing organisms, symptoms of TTX poisoning, and incidence worldwide.

Topics: Animals; China; Ciguatera Poisoning; Humans; Incidence; Indian Ocean; Japan; Mediterranean Sea; Tetraodontiformes; Tetrodotoxin; Thailand

Tetrodotoxin is one of the most potent neurotoxins in the aquatic world. This review of published and unpublished reports aims to describe the poisoning cases that have occurred in mainland France and overseas territories. Six articles were included, with 13 poisoning events, individuals or collective (number (

Topics: Animals; Ciguatera Poisoning; France; Humans; Neurotoxicity Syndromes; Tetraodontiformes; Tetrodotoxin

Food poisoning is encountered throughout the world. Many of the toxins responsible for specific food poisoning syndromes are no longer limited to isolated geographic locations. With increased travel and the ease of transporting food products, it is likely that a patient may present to any emergency department with the clinical effects of food poisoning. Recognizing specific food poisoning syndromes allows emergency health care providers not only to initiate appropriate treatment rapidly but also to notify health departments early and thereby prevent further poisoning cases. This article reviews several potential food-borne poisons and describes each agent's mechanism of toxicity, expected clinical presentation, and currently accepted treatment.

Topics: Botulinum Antitoxin; Botulism; Ciguatera Poisoning; Foodborne Diseases; Humans; Marine Toxins; Tetrodotoxin

Marine poisoning results from the ingestion of marine animals that contain toxic substances and causes substantial illness in coastal regions. Three main clinical syndromes of marine poisoning have important neurological symptoms-ciguatera, tetrodotoxin poisoning, and paralytic shellfish poisoning. Ciguatera is the commonest syndrome of marine poisoning and is characterised by moderate to severe gastrointestinal effects (vomiting, diarrhoea, and abdominal cramps) and neurological effects (myalgia, paraesthesia, cold allodynia, and ataxia), but is rarely lethal. Tetrodotoxin poisoning and paralytic shellfish poisoning are less common but have a higher fatality rate than ciguatera. Mild gastrointestinal effects and a descending paralysis are characteristic of these types of poisoning. In severe poisoning, paralysis rapidly progresses to respiratory failure. Diagnosis of all types of marine poisoning is made from the circumstances of ingestion (type of fish and location) and the clinical effects. Because there are no antidotes, supportive care, including mechanical ventilation in patients with severe paralysis, is the mainstay of treatment.

Topics: Animals; Ciguatera Poisoning; Fishes, Poisonous; Humans; Marine Toxins; Nervous System; Shellfish Poisoning; Tetrodotoxin

Seafood poisoning has been recognized as a problem in both coastal and inland populations for millennia. Many types of sea creatures from shellfish to the largest fish have been implicated. Severe cases of many different types of seafood poisonings can result in fatalities. While the pathophysiology of the toxins is well known in some cases, others, like ciguatera, remain somewhat confusing. As a result, the treatment of these conditions remains controversial, although supportive care continues to be the mainstay of therapy. In this manuscript, we review the pathophysiology, clinical presentation, and treatment of some of the most common and toxic varieties of seafood poisoning resulting from toxins.

Topics: Animals; Ciguatera Poisoning; Fishes; Humans; Kainic Acid; Marine Toxins; Paralysis; Seafood; Shellfish Poisoning; Tetrodotoxin

The consumption of seafood, which is contaminated by toxines of red tides, is a common cause of disease in tropic regions. The most important diseases, which are caused by red tides are Paralytic Shellfish Poisoning (PSP), Diarrhetic Shellfish Poisoning (DSP), Neurotoxic Shellfish Poisoning (NSP), Amnesic Shellfish Poisoning (ASP), Ciguatera Fish Poisoning (CFP).

Topics: Americas; Animals; Asia; Australia; Ciguatera Poisoning; Dinoflagellida; Europe; Fishes, Poisonous; Foodborne Diseases; Humans; Marine Toxins; Seafood; Tetrodotoxin

Three conditions that may occur after consumption of seafood--puffer fish poisoning, ciguatera, and paralytic shellfish poisoning--are caused by a group of poisons that block voltage-gated sodium channels in myelinated and non-myelinated nerves. The conditions cannot be distinguished clinically and so constitute an entity for which the name pelagic paralysis is proposed. Variations in the clinical features can be accounted for by large differences in the amount of toxin present in the seafood.

Topics: Animals; Ciguatera Poisoning; Fishes, Poisonous; Foodborne Diseases; Humans; Marine Toxins; Mollusca; Paralysis; Shellfish Poisoning; Terminology as Topic; Tetrodotoxin

The known and theoretical pharmacology of poisons involved in toxic marine ingestions has assisted in the development of specific therapeutics for these afflictions. The clinical manifestations of several toxic marine ingestions have suggested toxins/cogeners that may be involved in the poisoning process, providing direction for the development of diagnostic laboratory tests, including those for cyclic ethers. Future investigations should involve utilization of acetaminophen and indomethacin for chronic ciguatera fish poisoning, and the evaluation of the role of polycyclic ethers in the temperature sensation reversal phenomenon of both ciguatera and neurotropic shellfish poisoning.

Topics: Animals; Ciguatera Poisoning; Ciguatoxins; Fishes, Poisonous; Hallucinogens; Humans; Marine Toxins; Neurotoxins; Sea Cucumbers; Shellfish; Tetrodotoxin

Ciguatoxins (CTXs) are marine toxins that cause ciguatera fish poisoning, a debilitating disease dominated by sensory and neurological disturbances that include cold allodynia and various painful symptoms as well as long-lasting pruritus. Although CTXs are known as the most potent mammalian sodium channel activator toxins, the etiology of many of its neurosensory symptoms remains unresolved. We recently described that local application of 1 nM Pacific Ciguatoxin-1 (P-CTX-1) into the skin of human subjects induces a long-lasting, painful axon reflex flare and that CTXs are particularly effective in releasing calcitonin-gene related peptide (CGRP) from nerve terminals. In this study, we used mouse and rat skin preparations and enzyme-linked immunosorbent assays (ELISA) to study the molecular mechanism by which P-CTX-1 induces CGRP release. We show that P-CTX-1 induces CGRP release more effectively in mouse as compared to rat skin, exhibiting EC

Topics: Animals; Calcitonin Gene-Related Peptide; Calcium; Ciguatera Poisoning; Ciguatoxins; Enzyme-Linked Immunosorbent Assay; Humans; Hyperalgesia; Lidocaine; Male; Marine Toxins; Membrane Potentials; Mice; Mice, Transgenic; NAV1.1 Voltage-Gated Sodium Channel; NAV1.7 Voltage-Gated Sodium Channel; NAV1.9 Voltage-Gated Sodium Channel; Rats; Receptors, Calcitonin Gene-Related Peptide; Tetrodotoxin

Bivalve molluscs, the primary vectors of paralytic shellfish poisoning (PSP) in humans, show marked inter-species variation in their capacity to accumulate PSP toxins (PSTs) which has a neural basis. PSTs cause human fatalities by blocking sodium conductance in nerve fibres. Here we identify a molecular basis for inter-population variation in PSP resistance within a species, consistent with genetic adaptation to PSTs. Softshell clams (Mya arenaria) from areas exposed to 'red tides' are more resistant to PSTs, as demonstrated by whole-nerve assays, and accumulate toxins at greater rates than sensitive clams from unexposed areas. PSTs lead to selective mortality of sensitive clams. Resistance is caused by natural mutation of a single amino acid residue, which causes a 1,000-fold decrease in affinity at the saxitoxin-binding site in the sodium channel pore of resistant, but not sensitive, clams. Thus PSTs might act as potent natural selection agents, leading to greater toxin resistance in clam populations and increased risk of PSP in humans. Furthermore, global expansion of PSP to previously unaffected coastal areas might result in long-term changes to communities and ecosystems.

Topics: Amino Acid Sequence; Animals; Bivalvia; Cell Line; Ciguatera Poisoning; Drug Resistance; Electric Conductivity; Humans; Molecular Sequence Data; Mutation; Paralysis; Risk; Saxitoxin; Selection, Genetic; Sodium; Sodium Channel Blockers; Sodium Channels; Tetrodotoxin

Topics: Adaptation, Physiological; Animals; Biological Evolution; Bivalvia; Ciguatera Poisoning; Colubridae; Drug Resistance; Eukaryota; Humans; Salamandridae; Saxitoxin; Sodium; Sodium Channel Blockers; Sodium Channels; Tetrodotoxin

On his second voyage of discovery, Captain James Cook charted much of the South Pacific. The journey was long, from 1772 to 1775. During the exploration, the geographic, ethnographic, and scientific variety provided no shortage of work for the accompanying naturalists, astronomers, navigators, and painters. Culinary discoveries included new species of fish, many of which were sketched, dressed, and ultimately eaten. The examined journals and correspondence document clinical poisonings after ingestion of two different species of fish. The clinical findings are described and likely represent ciguatera and tetrodotoxin poisonings. Mechanisms of these toxin's actions are discussed in light of more recent studies.

Topics: Animals; Ciguatera Poisoning; Famous Persons; History, 18th Century; Humans; Male; Naval Medicine; Perciformes; Tetraodontiformes; Tetrodotoxin; United Kingdom

Consumption of seafood is increasing and physicians should know more about ichthyosarcotoxism, or fish-flesh poisoning. It appears in a variety of forms: poisoning, ciguatera, tetrodotoxin and scombroid poisoning. Ingestion of certain marine turtles and mammals also has been incriminated as the cause of illness. Paralytic shellfish poisoning can be deadly. In addition, red tide may cause respiratory problems.

Topics: Animals; Ciguatera Poisoning; Fishes; Foodborne Diseases; Humans; Marine Toxins; Sharks; Shellfish Poisoning; Tetrodotoxin; Turtles

Topics: Animals; Ciguatera Poisoning; Fishes, Poisonous; Foodborne Diseases; Humans; Tetrodotoxin

Topics: Adult; Animals; Child, Preschool; Ciguatera Poisoning; Female; Fishes, Poisonous; Humans; Male; Marine Toxins; Tetrodotoxin