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 [1].

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 [2] [3]. 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 [4].

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 [5].

• Nightmare

  Two families complained of a sensation of "electrical currents," tremors, muscle cramps, nightmares, hallucinations, agitation, anxiety and nausea of varying severity several hours after consuming rabbitfish ("aras"). [ncbi.nlm.nih.gov]

  Literally, it can cause nightmares; about 1 in 6 may experience signs of hallucinatory poisoning: lack of coordination, hallucinations, depression and nightmares. [nutritionfacts.org]

  […] tingling, or a burning sensation around mouth, hands, or feet; joint or muscle pains with weakness or cramps; vomiting, diarrhea, chills, itching, headache, sweating, and dizziness; reversal of temperature sensation in the mouth, unusual taste sensations; nightmares [mauinow.com]

  […] tingling, or a burning sensation around mouth, hands, or feet; Joint or muscle pains with weakness or cramps; Vomiting, diarrhea, chills, itching, headache, sweating, and dizziness; Reversal of temperature sensation in the mouth, unusual taste sensations; nightmares [health.hawaii.gov]

• Sepsis

  In addition to a lack of response to mannitol, clinical and laboratory indices of sepsis were present in this patient. [ncbi.nlm.nih.gov]

• Constitutional Symptom

  Constitutional symptoms may be misdiagnosed as chronic fatigue syndrome. A common source outbreak is easier to recognize and therefore notify to public health organizations. [ncbi.nlm.nih.gov]

• Dyspnea

  In severe cases, there may be rapid progression to breathing difficulties (dyspnea) and muscular paralysis. [rarediseases.org]

• Vomiting

  Do not induce vomiting or give syrup of Ipecac. Ipecac was formerly used to induce vomiting in poisoned patients where there was a chance to get the toxin out of the body. [rxlist.com]

  Some investigators have suggested vomiting should be induced if the victim is awake and alert and has eaten ciguatera toxin-containing fish within the last 3 to 4 hours. [emedicinehealth.com]

  She reported she had eaten eel at 7:00pm with friends the previous evening and had started vomiting soon after. Case 2 One hour later, a 67 year-old man self-presented with vomiting and diarrhoea. [nzma.org.nz]

• Nausea

  Two families complained of a sensation of "electrical currents," tremors, muscle cramps, nightmares, hallucinations, agitation, anxiety and nausea of varying severity several hours after consuming rabbitfish ("aras"). [ncbi.nlm.nih.gov]

  Symptoms include: nausea, vomiting, diarrhea, muscle pain, numbness, tingling, abdominal pain, dizziness, and vertigo. Hot and cold sensation may be reversed. [rxlist.com]

• Food Poisoning

  Another similar type of food poisoning is scombroid poisoning which is discussed separately. The symptoms of this are very similar to food poisoning but can last for a long period of time. [medic8.com]

  Abstract Ciguatera is a specific type of food poisoning associated with the ingestion of tropical fish, which, although normally safe for consumption, may at times contain high amounts of ciguatoxin, as well as other chemically related toxins. [ncbi.nlm.nih.gov]

  This is the third outbreak of ciguatera food poisoning in the Canary Islands in 2012. We describe the epidemiology of this outbreak. [eurosurveillance.org]

  Red Bass Ciguatera food poisoning is an unusual form of food poisoning most typically caused by larger and older fish that live in warm ocean waters. However smaller warm ocean water finfish may also be implicated. [foodsafety.asn.au]

  It's the most common form of fish-related food poisoning in the world, and according to a new study published online in the American Journal of Tropical Medicine and Hygiene, it just became even more common in the state of Florida. [fox13news.com]

• Abdominal Pain

  A 12-year-old Tongan female presented to our Emergency Department with mid-abdominal pain, nausea, change in mental status, and new-onset movement disorder after ingestion of jellyfish imported from American Samoa. [ncbi.nlm.nih.gov]

  The symptoms from ingesting Ciguatera toxin are similar to other types of food poisoning and may consist of nausea, vomiting, diarrhea, muscle pain, numbness, tingling, abdominal pain, dizziness, and vertigo. [intlfieldstudies.org]

  The onset of symptoms vary with the amount of toxin eaten from half an hour to up to two days and include: •nausea •vomiting •diarrhea •muscle pain •numbness •tingling •abdominal pain •dizziness •vertigo •Hot and cold sensations How is ciguatera treated [thebermudian.com]

  Within three hours of eating the fish, he developed abdominal pain, watery diarrhoea, and developed a burning sensation of the skin overnight that became very severe the next day while swimming. [pmj.bmj.com]

  The illness is characterized by abdominal pain, nausea, vomiting, and diarrhea. [iamat.org]

• Abdominal Cramps

  Individuals, who have come in contact with Ciguatera poisoning can “experience many symptoms including tingling and numbness in fingers, toes, around lips, tongue, mouth and throat; nausea, vomiting, diarrhea or abdominal cramps, joint pains, headache [edition.channel5belize.com]

  Common CFP symptoms include gastrointestinal problems like abdominal cramps, diarrhea, nausea, and vomiting followed by neurological symptoms. [www2.fgcu.edu]

  Most people experience some combination of flushing and rash on the face and upper body, sweating, diarrhea, and abdominal cramps. Sometimes, there is a burning, peppery taste in the mouth. Most people recover quickly without treatment. [poison.org]

• Hypotension

  We report two patients with persistent bradycardia and hypotension after eating mackerel fish. [heartviews.org]

  He was found to be profoundly bradycardic (HR 30 bpm) and hypotensive (BP 72/35 mm Hg). His vital signs improved with atropine. [nzma.org.nz]

  Cardiovascular findings include bradycardia and hypotension. Signs of shock may be observed. [emedicine.medscape.com]

  We “support” the patient while he/she has nausea, vomiting, tingling, numbness, bradycardia, hypotension, muscle cramps, and tooth pain — and thinks that cold things are hot and hot things cold. No anti-toxin, no antibiotic, sorry. [blogs.jwatch.org]

• Metallic Taste

  Headaches, muscle aches, and numbness are common; other symptoms may include strange sensations, such as the feeling of loose teeth, confusion between hot and cold temperatures, or a metallic taste in the mouth. [www2.fgcu.edu]

  CFP symptoms include: Nausea Stomach Cramps Diarrhea General Weakness Dizziness Itching Increased or Decreased Heart Rate Rarely - Paralysis & Coma Headache Muscular Pain Metallic Taste in the Mouth Tooth Pain Numbness Temperature Reversal (hot feels [bareboatsbvi.com]

  Some people may have neurologic symptoms, such as a tingling sensation, tooth pain or feeling as if the teeth are loose, itching, a metallic taste in the mouth, and blurred vision. [wwwnc.cdc.gov]

  This is followed by neurological complications appearing 3 to 72 hours later, including a tingling sensation, temperature reversal (cold items feel hot and hot items feel cold), itching, metallic taste in the mouth, feeling like teeth are loosening, blurred [iamat.org]

• Pruritus

  This was followed by neurological symptoms 24-48 hours later, including temperature reversal (paradoxical dysaesthesia), intense pruritus and increased nociception as a result of a small fibre peripheral neuropathy. [ncbi.nlm.nih.gov]

  About two days later, the husband and wife experienced severe generalized pruritus. [cmaj.ca]

  […] bass and–unlike scombroid poisoning, may cause morbidity regardless of the form of preparation Clinical Onset 6-12 hrs after ingestion; N&V, cramping, diarrhea, paresthesias, reversal of temperature sense, arthralgias, myalgias, cranial nerve palsies, pruritus [medical-dictionary.thefreedictionary.com]

• Skin Lesion

  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. [symptoma.com]

• Arthralgia

  […] abdominal discomfort, nausea) within 24 hours, and/or neurological symptoms (temperature dysesthesia [i.e. touch cold/hot objects and feel opposite temperature], paresthesia [numbness] in extremities, generalized pruritis, blurry vison, headache, myalgia, arthralgia [bccdc.ca]

  […] grouper, red snapper, amberjack, surgeonfish, sea bass and–unlike scombroid poisoning, may cause morbidity regardless of the form of preparation Clinical Onset 6-12 hrs after ingestion; N&V, cramping, diarrhea, paresthesias, reversal of temperature sense, arthralgias [medical-dictionary.thefreedictionary.com]

  Neurologic symptoms may include the following: Lingual and circumoral paresthesias Painful paresthesias of the extremities Paradoxical temperature reversal (eg, cold objects feel hot and hot objects feel cold) Dental pain (teeth feel loose) Pruritus Arthralgias [emedicine.medscape.com]

  Chills, hot and cold temperature reversal, generalized weakness, restlessness, dizziness, wheezing, blurred vision, abnormal sensitivity to light (photophobia), muscle aches (myalgias), and/or joint pain (arthralgias) may also develop. [rarediseases.org]

• Circumoral Paresthesia

  Neurologic symptoms may include the following: Lingual and circumoral paresthesias Painful paresthesias of the extremities Paradoxical temperature reversal (eg, cold objects feel hot and hot objects feel cold) Dental pain (teeth feel loose) Pruritus Arthralgias [emedicine.medscape.com]

  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. [symptoma.com]

• Headache

  Complications include long term fatigue, persistent headaches and difficulty with balance and co-ordination. Treatment for ciguatera poisoning Ciguatera poisoning cannot be cured. [medic8.com]

  […] vomiting, diarrhea, abdominal discomfort, nausea) within 24 hours, and/or neurological symptoms (temperature dysesthesia [i.e. touch cold/hot objects and feel opposite temperature], paresthesia [numbness] in extremities, generalized pruritis, blurry vison, headache [bccdc.ca]

  Individuals, who have come in contact with Ciguatera poisoning can “experience many symptoms including tingling and numbness in fingers, toes, around lips, tongue, mouth and throat; nausea, vomiting, diarrhea or abdominal cramps, joint pains, headache [edition.channel5belize.com]

  Headaches, muscle aches, and numbness are common; other symptoms may include strange sensations, such as the feeling of loose teeth, confusion between hot and cold temperatures, or a metallic taste in the mouth. [www2.fgcu.edu]

• Dizziness

  They include a very slow heart rate and high blood pressure which can cause dizziness and physical weakness. Sweating, chills and a stiff neck are other symptoms of ciguatera poisoning. [medic8.com]

  Symptoms include vomiting, itching, dizziness, and a burning sensation around the mouth, hands and feet. People who have ciguatera may also find that cold things feel hot and hot things feel cold. Ciguatera has no cure. [khon2.com]

  The symptoms from ingesting Ciguatera toxin are similar to other types of food poisoning and may consist of nausea, vomiting, diarrhea, muscle pain, numbness, tingling, abdominal pain, dizziness, and vertigo. [intlfieldstudies.org]

  The onset of symptoms vary with the amount of toxin eaten from half an hour to up to two days and include: •nausea •vomiting •diarrhea •muscle pain •numbness •tingling •abdominal pain •dizziness •vertigo •Hot and cold sensations How is ciguatera treated [thebermudian.com]

  Symptoms can include numbness, tingling, or a burning sensation around mouth, hands, or feet; joint or muscle pains with weakness or cramps; vomiting, diarrhea, chills, itching, headache, sweating, and dizziness; reversal of temperature sensation in the [mauinow.com]

• Paresthesia

  However, symptoms of peripheral neuropathy with paresthesias and paradoxical disturbance of thermal sensation are the hallmark. Electrophysiological studies are often normal, except in severe cases. [ncbi.nlm.nih.gov]

  Notes Clinical illness defined as: gastrointestinal symptoms (vomiting, diarrhea, abdominal discomfort, nausea) within 24 hours, and/or neurological symptoms (temperature dysesthesia [i.e. touch cold/hot objects and feel opposite temperature], paresthesia [bccdc.ca]

  […] of fish are implicated–eg, barracuda, grouper, red snapper, amberjack, surgeonfish, sea bass and–unlike scombroid poisoning, may cause morbidity regardless of the form of preparation Clinical Onset 6-12 hrs after ingestion; N&V, cramping, diarrhea, paresthesias [medical-dictionary.thefreedictionary.com]

  He also had paresthesias of the mouth and extremities, and cold allodynia. Most of his symptoms resolved after 4 weeks, however the cold allodynia persisted for several months. [calpoison.org]

• Dysesthesia

  Sequelae include chronic dysesthesia, which may be relieved by amitriptyline. [pmj.bmj.com]

  Notes Clinical illness defined as: gastrointestinal symptoms (vomiting, diarrhea, abdominal discomfort, nausea) within 24 hours, and/or neurological symptoms (temperature dysesthesia [i.e. touch cold/hot objects and feel opposite temperature], paresthesia [bccdc.ca]

  […] like a standard case of gastroenteritis — nausea and vomiting — but since ciguatera is a neurotoxin, here’s some of the weird stuff that follows : tingling, numbness, bradycardia, hypotension, muscle cramps, tooth pain, and most famously, “paradoxical dysesthesias [blogs.jwatch.org]

  […] symptoms Typical presentation GI symptoms initially: diarrhea, nausea, and vomiting These symptoms typically last just a few days followed by weakness and fatigue, with occasional hypotension or bradycardia Features of peripheral neuropathy including dysesthesia [litfl.com]

• Neurologic Manifestation

  Ciguatera poisoning causes a distinct clinical syndrome characterized primarily by gastrointestinal and neurologic manifestations [1]. [annals.org]

  Later on, neurological manifestations set in. [jpgmonline.com]

  Serious neurological manifestations of ciguatera: is the delay unusually long? J Neurol Neurosurg Psychiatry. 1998;64:688-89. [rarediseases.org]

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 [6] [7].

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 [8].

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 [9].

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 [10].

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10. Tsumuraya T, Fujii I, Hirama M. Production of monoclonal antibodies for sandwich immunoassay detection of Pacific ciguatoxins. Toxicon. 2010;56(5):797-803.