ciguatoxins and Diarrhea

Ciguatera is a common marine, toxin-borne illness caused by the consumption of fish that contain toxins that activate voltage-sensitive sodium channels. The clinical manifestations of ciguatera are typically self-limited, but chronic symptoms may occur in a minority of patients. This report describes a case of ciguatera poisoning with chronic symptoms, including pruritus and paresthesias. A 40-y-old man was diagnosed with ciguatera poisoning after consuming amberjack while vacationing in the US Virgin Islands. His initial symptoms, including diarrhea, cold allodynia, and extremity paresthesias, evolved into chronic, fluctuating paresthesias and pruritus that became worse after the consumption of alcohol, fish, nuts, and chocolate. After a comprehensive neurologic evaluation failed to reveal another cause for his symptoms, he was diagnosed with chronic ciguatera poisoning. His neuropathic symptoms were treated with duloxetine and pregabalin, and he was counseled to avoid foods that triggered his symptoms. Chronic ciguatera is a clinical diagnosis. Signs and symptoms of chronic ciguatera can include fatigue, myalgias, headache, and pruritus. The pathophysiology of chronic ciguatera is incompletely understood but may involve genetic factors or immune dysregulation. Treatment involves supportive care and avoidance of foods and environmental conditions that may exacerbate symptoms.

Topics: Animals; Ciguatera Poisoning; Ciguatoxins; Diarrhea; Male; Marine Toxins; Paresthesia

The frequency and scale of Harmful Algal Bloom (HAB) and marine algal toxin incidents have been increasing and spreading in the past two decades, causing damages to the marine environment and threatening human life through contaminated seafood. To better understand the effect of HAB and marine algal toxins on marine environment and human health in China, this paper overviews HAB occurrence and marine algal toxin incidents, as well as their environmental and health effects in this country. HAB has been increasing rapidly along the Chinese coast since the 1970s, and at least 512 documented HAB events have occurred from 1952 to 2002 in the Chinese mainland. It has been found that PSP and DSP toxins are distributed widely along both the northern and southern Chinese coasts. The HAB and marine algal toxin events during the 1990s in China were summarized, showing that the HAB and algal toxins resulted in great damages to local fisheries, marine culture, quality of marine environment, and human health. Therefore, to protect the coastal environment and human health, attention to HAB and marine algal toxins is urgently needed from the environmental and epidemiological view.

Topics: Amnesia; Animals; China; Ciguatoxins; Diarrhea; Dinoflagellida; Environment; Eukaryota; Eutrophication; Fisheries; Food Contamination; Foodborne Diseases; Humans; Kainic Acid; Lethal Dose 50; Marine Toxins; Neurotoxicity Syndromes; Okadaic Acid; Oxocins; Paralysis; Seawater; Shellfish Poisoning

Ciguatera poisoning appears after ingestion of contaminated fish from tropical coral reefs. Due to the diversity of clinical symptoms and the absence of a specific test in humans, the diagnosis is often difficult.. A retrospective study of 10 patients consulting for a clinical and epidemiological picture compatible with ciguatera poisoning after a trip to tropical countries between 1993 and 2000.. Most infections but one were acquired in the Caribbean area and there were 8 females. Clinical manifestations started within the first 24 hours after fish ingestion. Chief symptoms were diarrhea and nausea, followed by neurological symptoms, mainly limbs paresthesias that persisted for several weeks.. The severity of clinical symptoms was variable and not related to age or initial symptoms. Ciguatera poisoning has to be considered in the diagnosis of acute gastroenteritis affecting travellers to tropical areas.

Topics: Adolescent; Adult; Ciguatera Poisoning; Ciguatoxins; Diagnosis, Differential; Diarrhea; Female; Humans; Male; Middle Aged; Retrospective Studies; Spain; Travel

A benthic toxic dinoflagellate identified as Prorocentrum lima (Syn. Exuviaella lima), and designated as strain PRL-1, was isolated from the coast of El Pardito (Coyote) Island in Baja California Sur, Mexico, after a fisherman poisoning incident involving consumption of liver from Lutjanus colorado, and Mycteroperca prionura fish. Purification and culturing was done in ES-Si medium, under 12:12 light/dark cycle (4 x 20 W cool-white fluorescent lamps), at 22 degrees C and constant stirring during 28 days. Whole cells were toxic to Artemia franciscana and its methanolic extract to mouse and to the marine yeast Debaryomyces hansenii. Chromatographic analysis (TLC and HPLC-MS) of such extract indicated an unusual proportion (1:2) okadaic acid (OA) and dinophysistoxin-1 (DTX-1). Estimated total toxin content by mouse bioassay (based on OA toxicity) was 19 pg/cell, a value significantly higher than that found by HPLC-MS (about 5.2 pg/cell, taking into account OA and DTX-1 only), suggesting that additional toxic components of unidentified nature are detected with the bioassay. This is the first report of a successful isolation and culturing of a toxic dinoflagellate from the Gulf of California, Mexico.

Topics: Animals; Chromatography, Thin Layer; Ciguatera Poisoning; Ciguatoxins; Diarrhea; Dinoflagellida; Foodborne Diseases; Mexico; Mice; Okadaic Acid; Pyrans; Risk Assessment; Shellfish

Topics: Adult; Aerospace Medicine; Child; Ciguatoxins; Diagnosis, Differential; Diarrhea; Female; Foodborne Diseases; Humans; Hypotension; Male; Peripheral Nervous System Diseases; Physical Examination

Topics: Amnesia; Animals; Bacterial Toxins; Ciguatoxins; Diarrhea; Dinoflagellida; Eukaryota; Fishes; Fishes, Poisonous; Food Contamination; Foodborne Diseases; Humans; Marine Toxins; Neurotoxins; Paralysis; Shellfish; Shellfish Poisoning; Syndrome; United Kingdom

Diarrhea and morphological influences on digestive tracts caused by ciguatoxin (CTX) were observed in mice microscopically. The lethal doses and clinical symptoms caused by i.p. administration were almost the same as those by p.o., the prominent difference being diarrhea that was caused only by i.p. route. The diarrhea was caused by a dose from 1/7 MU to 1 MU of CTX (MU: mouse unit, to kill a mouse of 15 g in 24 hr, corresponding to 7 ng of pure CTX), but not at lower or higher doses. In this study, we used an i.p. dose of 4/5 MU (10.4 ng/28 g). Diarrhea started within 10 min after administration and lasted until 30 min. The changes were observed in the large intestine; namely, CTX accelerated mucus secretion and peristalsis in the colon and stimulated defecation at the rectum, resulting in prominent diarrhea. In the colon, a large quantity of mucus was secreted from even immature goblet cells, and epithelial cell damages were observed in the upper portion of the large intestine but not in the latter half. The morphological changes caused by CTX in the upper portion of the large intestine were similar to those seen with cholera toxin.

Topics: Animals; Ciguatoxins; Colon; Diarrhea; Disease Models, Animal; Injections, Intraperitoneal; Intestine, Large; Male; Mice; Microscopy, Electron, Scanning; Peristalsis; Rectum; Tissue Fixation

Ciguatera fish poisoning is a clinical syndrome consisting of a combination of gastrointestinal and neurological symptoms occurring after eating toxin-containing tropical reef fish; it is a major cause of morbidity in Hawaii, the South Pacific, Australia, and the Caribbean. In an effort to define pathophysiological mechanisms responsible for the diarrheal component of the illness, we examined the effect of crude and fractionated toxin preparations on isolated rabbit ileal tissue in a Ussing chamber model. Both the crude toxin preparation (prepared from toxic Ctenochaetus strigosus) and 10% and 50% methanol-chloroform toxin fraction (prepared from a pool of toxic fish samples) gave a striking increase in transepithelial electrical potential difference and short-circuit current. Enterotoxic activity seemed to be mediated by calcium. When examined by light microscopy, the intestinal mucosa was not damaged by the toxin preparations used. Our data demonstrate that toxins involved in ciguatera fish poisoning directly stimulate intestinal fluid secretion without accompanying tissue damage and suggest that calcium is the "second messenger" mediating the process.

Topics: Animals; Biological Assay; Calcium; Calcium-Binding Proteins; Ciguatoxins; Diarrhea; Diffusion Chambers, Culture; Dose-Response Relationship, Drug; Electrophysiology; Ileum; Intestinal Mucosa; Intestinal Secretions; Male; Models, Biological; Rabbits

Clinical data were obtained on 33 patients involved in 27 episodes of ciguatera fish poisoning occurring during a 14-week period on St Thomas in the US Virgin Islands. All patients had gastrointestinal tract symptoms, with 30 patients (91%) complaining of diarrhea and 23 patients (70%) complaining of vomiting; these symptoms occurred early in the disease and were of short duration. Twenty-three patients (70%) complained of malaise, and 19 patients (58%) had pain and weakness in the lower extremities. Dysesthesias were noted by 19 patients (58%); the median duration of dysesthesias was two weeks or more, with symptoms present is some cases for more than two months. Cardiovascular signs and symptoms, including both hypotension and bradycardia were noted in some acute cases. Therapy included antidiarrheal and antiemetic agents, intravenous fluids, atropine, and pralidoxime chloride. Efficacy of pralidoxime therapy could not be established on the basis of our data.

Topics: Adolescent; Adult; Aged; Animals; Blood Pressure; Child; Child, Preschool; Ciguatoxins; Diarrhea; Dinoflagellida; Disease Outbreaks; Female; Fishes; Foodborne Diseases; Heart Rate; Humans; Infant; Male; Marine Toxins; Middle Aged; Neurologic Manifestations; United States Virgin Islands; Vomiting