Food poisoning or gastroenteritis is a common diagnosis for individuals who have nausea, vomiting and diarrhea after ingestion of fish. When also manifesting neurological symptoms, these are blamed on puffer fish poisoning, but ciguatera fish poisoning (CFP) can also manifest only with gastroenteritis, without neurological complications and remain undiagnosed. We report patients who fulfilled criteria of CFP suffering from severe GI disturbances, neurological manifestations, compromised cardiovascular status and autonomic dysfunction. All recovered within 1 - 3 days with supportive treatment. There were two small outbreaks: one in Bangkok in 2007 (2 patients) and another (2009) in Phuket (4 patients). All patients consumed the same unidentified fish portion and had severe GI symptoms. One had acute ventilatory failure requiring intubation whereas the remaining had neurological disturbances consisting of paresthesia, severe vertigo and ataxia. Absence of reflex tachycardia was noted in all patients who had severe volume depletion and shock. The most severe patient could be extubated within 24 hours and was discharged in 48 hours. All of the remaining recovered completely within 48 hours. Severe abdominal pain, nausea and vomiting and autonomic dysfunction in the form of bradycardia in the presence of hypotension were seen. Dramatic recovery within 48 hours occurred in all cases. None of the fish considered to have been responsible was available for testing. Physicians should be aware of CFP intoxication in the differential diagnosis of gastroenteritis-like syndromes after eating seafood.
The most common marine toxin worldwide is ciguatera. Many types of reef-fish are vulnerable to accumulate ci- guatera toxin (CTX). This is particularly true for barracuda, grouper, sea bass, snapper, and amberjack [
CTX is a lipophillic polyether that can open voltage sensitive Na+ channels at the neuromuscular junction. It causes hyper-excitability and inhibits synaptic transmission. Ingesting fish meat containing CTX produces an illness very much similar to other food poisoning or gastrointestinal infections. The majority of patients begin to have signs and symptoms of ciguatera within 6 - 10 hours (range 1 - 48) [
It is difficult to distinguish between puffer fish poisoning and ciguatera toxin. Clinical symptoms of puffer fish poisoning result from tetrodotoxin, a heat-stable and water-soluble molecule that inhibits Na+ channel and post-synaptic acetylcholine receptors [
Marine fish poisoning, although common, has been largely ignored and the frequency is underestimated [
We report six patients from two incidents in 2007 and 2009. The first two were admitted to King Chulalongkorn Memorial Hospital (KCMH) in Bangkok after ingesting contaminated sea bass. The remaining four, were admitted to Phuket Provincial hospital. We included these patients based on the presence of severe diarrhea, nausea and vomiting, absence of reflex tachycardia, and dramatically recovery of clinical symptoms and signs with- in 24 - 72 hours despite a severe degree of cardiovascular and neuromuscular systems involvement at nadir.
Patient 1 was a 20-year-old pharmacy student. She was previously healthy. On August 31st 2007, she had lunch at the dormitory cafeteria, consisting of rice with sea bass. One hour after that, she gradually felt numbness at the perioral area. The numbness progressed to both hands and feet within a few hours. She had dizziness and became clumsy while walking. In the following morning she woke up with severe fatigue, vertigo, nausea and vomiting. Ataxia was noted. She was immediately taken to the hospital. Upon admission, her vital signs were normal with a blood pressure of 110/60 mmHg, a heart rate of 70 beats per minute. There was no significant focal neurological deficit except for abnormal balance of maintaining posture and ataxia without side predilection. Sensory examination was normal in all modalities. Deep tendon reflexes were normal at 1+. She received intravenous fluid and antiemetic drug. She was discharged after one day with no sequelae (
Patient 2 was a 35-year-old nurse who had been working at King Chulalongkorn Memorial Hospital (KCMH). She had eaten bass with Chinese celery for lunch at the same canteen and the same day as Patient 1. Half-an- hour after her meal, she had abdominal pain and diarrhea. A diminished sensation at perioral area and at both hands was also noted shortly after onset. Within a few hours, her numbness increased in severity. She also felt dizzy, and experienced severe nausea and vomiting. At the emergency department, she was noted having dyspnea which progressed to impending respiratory failure. Two hours later, she developed hoarseness of voice and weakness of all extremities grade 4/5 with preservation of deep tendon reflexes. Her peak respiratory flow was recorded to be less than 300 milliliters and her peripheral oxygen saturation was 57%. Blood pressure was 144/100 mmHg. Her heart and respiratory rates showed no compensatory responses to severe hypoxia. Heart rate was at 80 beats per minute and respiratory rate was only 20 times per minute. She subsequently developed severe generalized weakness and required end otracheal intubation. Neurology consultation was requested to exclude a diagnosis of brainstem stroke. Upon examination, her muscle tone was flaccid. She had normal pupillary size and responses to light and no abnormal brainstem signs. She was then admitted to the intensive care
. Patients data
Patient No. | Patient 1 | Patient 2 | Patient 3 | Patient 4 | Patient 5 | Patient 6 |
---|---|---|---|---|---|---|
Year | 2007 | 2007 | 2009 | 2009 | 2009 | 2009 |
Age (year) | 20 | 50 | 9 | 24 | 29 | 34 |
Hometown | Bangkok | Bangkok | Phuket | Phuket | Phuket | Phuket |
Gender | Female | Female | Male | Male | Female | Female |
Onset of symptom | 1 hr after meal (16 hrs prior to admission) | 30 min after meal (6 hrs prior to admission) | 2 hrs after meal (4 hrs prior to admission) | 2 hrs after meal (4 hrs prior to admission) | 4 hrs after meal (4 hrs prior to admission) | 2 hrs after meal (3 hrs prior to admission) |
Symptoms | Perioral/hands/feet numbness, ataxia, vertigo, nausea & vomitting | Abdominal pain, diarrhea, perioral numbness, nausea & vomiting | Diarrhea, perioral & tongue numbness, nausea & vomiting | Abdominal pain, perioral /legs numbness, nausea, vomiting, diarrhea | Diarrhea, Perioral/hands/feet numbness, nausea, vomiting, abdominal pain, cramping | Diarrhea, nausea, vomiting, abdominal pain, cramping, perioral/ hands/feet numbness |
History of food taking | Sea bass with Chinese celery | Sea bass with Chinese celery | Red snapper fish curry | Red snapper fish curry | Red snapper fish curry | Red snapper fish curry |
Underlying | No | Dyslipidemia | No | No | No | No |
Vital signs | Normal | Respiratory failure | Hypotension | Normal | Hypotension | Hypotension |
Conscious | Normal | Normal | Normal | Normal | Normal | Normal |
Neurosigns | Normal (improved) | Horseness of voice, quadriparesis with normal reflexes | Not significant | Not significant | Not significant | Not significant |
CBC | Normal | Normal | NA | NA | NA | Leukocytosis |
Electrolyte | Normal | Normal | NA | NA | NA | NA |
Ventilator support | No | Yes | No | No | No | No |
Result | Recover in 1 day | Recover in 3 days | Recover in 1 day | Recover in 1 day | Recover in 1 day | Recover in 1 day |
unit (ICU) where she received intravenous fluid and other supportive care including respiratory support. Laboratory investigations revealed normal electrolytes and other blood chemistry. She was on ventilatory support for 24 hours and fully recovered three days after admission (
Patients 3, 4, 5, and 6 were in the same family. On December 12th, 2009 patient 6 prepared red snapper consisting of curry and pork rib soup with salted vegetables. All the twelve members of the family shared the same dinner but only four developed symptoms.
Patient 3 was a 9-year-old boy. Two hours after dinner, he experienced nausea, vomiting and abdominal pain with watery diarrhea (more than 20 stools). He also experienced numbness at his legs, tongue, and perioral region. He was brought to Phuket Provincial Hospital where he was observed to have hypotension and signs of volume depletion with systolic blood pressure lower than 90 mmHg and a heart rate of 80 beats per minute. Neurological examination was within normal limit. The numb feeling around his mouth and legs resolved within 24 hours after he received supportive care and intravenous fluid replacement (
The second member of the family was patient 4. He was a healthy man 24 years of age. Six hours after dinner, when his nephew (patient 3) was hospitalized, he also had nausea and vomiting. He began to feel abdominal cramping, diarrhea and headache. He also noted perioral numbness; of tongue, both hands and feet. Physical examination showed that he was febrile and moderately dehydrated with hypotension (blood pressure of 80/40 mmHg) and had a heart rate of 48 per minute. There were no abnormal neurological signs (
Patient 5, a 29-year-old housewife, had the longest incubation period of all. She developed symptoms 8 hours after the joint meal. She had nausea, vomiting and watery diarrhea of more than 10 stools along with abdominal pain, perioral numbness and also numbness of hands and feet. Vital signs at admission were normal except for a slow heart rate of 52 beats per minute with a blood pressure of 110/60 mmHg. There was no neurological deficit. Her blood tests were normal. She was admitted for one day observation and received intravenous fluids, antispasmodics and antiemetics (
Patient 6 was a 34-year-old previously healthy female. She was the one who prepared the food for the whole family. Her symptoms occurred 5 hours after the meal, comprising of perioral and limb numbness, abdominal pain, diarrhea, nausea and vomiting. Physical examination on admission revealed a blood pressure of 90/60 mmHg and a relative sinus bradycardia of 50 beats per minute. She was fully conscious and had no neurological deficits. Her laboratory investigations were within normal limits except leukocytosis of 18,700 cells/mm3. She was admitted for observation for 24 hours and was prescribed only antiemetics and oral rehydration salts. She completely recovered at the time of discharge. Patient 1 had abnormal slow heart rates of 40 - 50 beats/minute whilst in the presence of hypotension/volume depletion and/or hypoxemia. All patients had nausea, vomiting and diarrhea (except patient 1 who had nausea and vomiting).
There are many marine toxins that can cause human diseases after ingesting contaminated food. A history of eating fish points to ciguatera or puffer fish poisoning, whereas consuming shellfish may suggest paralytic, neuro- toxic oramnesic shellfish poisoning [
In 1984, there was one reported case of ciguatoxin poisoning of an Italian visitor who had ingested ocean fish in Thailand [
Treatment of CTX poisoning is mainly supportive and symptomatic, such as volume replacement. There are reports suggesting that mannitol, 0.5 - 1 g/kg as an intravenous drip in 30 - 45 minutes within 48 - 72 hours after onset, would help improve the severity of symptoms. Authors believed that due to high osmolarity, mannitol could reduce neuronal edema and act as scavenger of free radicals [
Prevention of ciguatera intoxication is difficult. It is colorless, odorless and has no characteristic taste. Most importantly, CTX is resistant to heat and cannot be destroyed by cooking. The current recommendation is that one should avoid eating internal organs of high risk fishe, such as Moray eel, Barracuda (Pla-saak-yai), Grouper (Pla- Kao), Kingfish (Pla-sam-lee), Jacks (Pla-ka-mong), Snapper (Pla-kra-pong), Surgeonfish(Pla-kee-tung-bet), Parrot fish (Pla-nok-kaew), Wrasses (Pla-nok-khun-tong), Hogfish, Narrow barred Spanish mackerel (Pla-in-see-bung), Coral trout (Pla-kud-slade), Flowery cod (Pla-ka-rang-siae) and Red emperor (Pla-kra-pong-daeng). If this is not avoidable, it has been suggested to consume ONLY small amounts of the same fish (<50 g) [
Recent studies have suggested that the increased incidence of ciguatera fish poisoning (CFP) correlates with
. Clinical symptoms of ciguatera and puffer fish poisoning [4] [6] [10] -[12]
Neurological symptoms | Symptoms | Tetrodotoxin | Ciguatoxin |
---|---|---|---|
Perioral numbness | 71% - 68% | 38% - 91% | |
Generalized paresthesia | 34% - 44% | 36% - 100% | |
Temperature dysesthesia | - | 19% - 94% | |
Vertigo | 22% - 30% | 25% - 62% | |
Nausea and vomiting | 45% - 48% | 37% - 69% | |
Headache | 40% - 47% | 19% - 62% | |
Limbs weakness | 22% - 62% | 30% - 100% | |
Myalgia | - | 34% - 86% | |
Ataxia | 0% - 15% | Rare | |
Coma | 0% - 11% | - | |
Respiratory failure | 0% - 22% | Rare | |
Gastrointestinal symptoms | |||
Abdominal pain | 17% - 22% | 30% - 74% | |
Diarrhea | 0% | 67% - 83% | |
Autonomic nervous system symptoms | |||
Hypersalivation | 0% - 7.5% | - |
global warming and other environment disturbances [
This research was sponsored by the Thailand Research Fund (DBG5180026), the Thai Red Cross Society, Thailand, and the US Naval Health Research Center BAA-10-93 under Cooperative Agreement Number W911NF-11-2-004. The views and conclusions contained in this document are those of the authors.