Domoic acid is the cause of amnestic shellfish poisoning. Severe symptoms of amnestic shellfish poisoning are altered mental status, memory loss, arrhythmias, hypotension, and seizure. Other associated symptoms include gastrointestinal disturbances and focal neurologic signs such as hemiparesis and ophthalmoplegia. Symptoms usually begin about 6 hours after ingestion but may occur as late as 2 days after ingestion. Neurologic and memory symptoms often persist even after the other symptoms of poisoning have improved and can be chronic in some instances.
Domoic acid is a neurotoxic amino acid produced by algae. Humans indirectly ingest the toxin through shellfish. Outbreaks have occurred on the coasts of North America and Europe.
There is no commonly available test to directly detect toxin ingestion. Treatment is supportive.
Emergency: requires immediate attention
Domoic acid poisoning
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Codes
ICD10CM:
T61.784A – Other shellfish poisoning, undetermined, initial encounter
SNOMEDCT:
95878009 – Amnesic shellfish poisoning
T61.784A – Other shellfish poisoning, undetermined, initial encounter
SNOMEDCT:
95878009 – Amnesic shellfish poisoning
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- Scombroid food poisoning
- Ciguatera food poisoning
- Hepatitis A virus infection
- Botulism
- Gastroenteritis
- Encephalitis
- Meningitis (eg, viral, bacterial, fungal)
- Influenza
- Seizure
- Cholinergic toxicity
- Anticholinergic toxicity
- Drug side effects (benzodiazepines, antihistamines, antipsychotics, opioids)
- Electrolyte disturbance (eg, hyponatremia)
- Cerebrovascular accident / stroke
- Multiple sclerosis
- Acute disseminated encephalomyelitis
- Neuromyelitis optica
- Toxoplasmosis
- Neurocysticercosis
- Sepsis
- Thrombotic thrombocytopenic purpura / hemolytic uremic syndrome
- Acute inflammatory demyelinating polyneuropathy
- Myocardial infarction
- Arrhythmia (see acute coronary syndrome, coronary artery disease)
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Last Reviewed:02/05/2019
Last Updated:09/16/2020
Last Updated:09/16/2020