Overview
Amnesic shellfish poisoning (ASP) results from consumption of shellfish contaminated with domoic acid, leading to a syndrome characterized by acute onset of confusion, disorientation, and memory impairment, often resembling an amnesic syndrome 12.Diagnosis
Clinical Presentation: Acute confusion, disorientation, memory impairment, and in severe cases, seizures and coma 12.
Neuropsychological Testing: Essential for assessing anterograde and retrograde amnesia, particularly noting temporal gradients in memory deficits 2.
Imaging: MRI or CT scans may show nonspecific findings; diffusion tensor imaging could highlight disruptions in the mammillothalamic tract 2.
Laboratory Tests: Detection of domoic acid in shellfish or patient samples confirms exposure 1.Management
Supportive Care: Focus on maintaining airway, ventilation, hydration, and managing seizures 1.
Monitoring: Close neurological monitoring for progression of symptoms and complications 1.
No Specific Anticonvulsants or Antidotes: Currently, no specific antidote for domoic acid poisoning exists; treatment is largely supportive 1.Special Populations
Elderly: More susceptible to severe neurological sequelae due to pre-existing cognitive vulnerabilities 1.
Comorbidities: Patients with underlying neurological conditions may exhibit more pronounced memory deficits and prolonged recovery 1.Key Recommendations
Confirm Exposure: Detect domoic acid in patient samples or implicated shellfish to confirm diagnosis (Evidence: Moderate) 1.
Supportive Neurological Care: Prioritize supportive measures including airway management and seizure control (Evidence: Expert opinion) 1.
Neuropsychological Assessment: Utilize neuropsychological testing to evaluate memory deficits, particularly distinguishing anterograde from retrograde amnesia (Evidence: Moderate) 2.References
1 Kopelman MD. What does a comparison of the alcoholic Korsakoff syndrome and thalamic infarction tell us about thalamic amnesia?. Neuroscience and biobehavioral reviews 2015. link
2 Park KC, Yoon SS, Chang DI, Chung KC, Ahn TB, Ku BD et al.. Amnesic syndrome in a mammillothalamic tract infarction. Journal of Korean medical science 2007. link