Skip to main content

Organic Amnestic Syndrome and Korsakoff Psychosis

Image
By

Organic Amnestic Syndrome and Korsakoff Psychosis

Dr Waleed Ahmad

Vignette

A 30-year-old woman is brought to you with memory deficits and rigid behaviour. On examination, she appears lean and weak, dishevelled, is disoriented to time, has a flat affect, registration is 3/3, short-term memory is 0/3 and long-term memory appears intact. She does not have any difficulty naming objects. On physical examination, her weight is 42Kg and her height 152 cm. The lady says, there is nothing wrong with her, while her father says she is speaking too many lies these days. The rest of the clinical evaluation is insignificant except for chronic diarrhoea and recent episodes of vomiting. 

What finding will you look for on MRI?

Diagnosis

The clinical picture, in this case, is consistent with organic amnestic syndrome, specifically Korsakoff Psychosis. The most common cause of organic amnestic syndrome is thiamine deficiency.(1)

Magnetic Resonance Imaging

Increased signal (ie, hyperintensity) in midline structures occurs in the acute Korsakoff psychosis. 

Laboratory test

Red cell transketolase activity is the most specific test for Korsakoff psychosis. 

Other causes: 

  1. Diencephalic amnesia
  2. Infarct in medial thalamus
  3. Tumour in medial thalamus
  4. Encephalitis
  5. Head injury

Causes of thiamine deficiency

  1. Alcoholism
  2. Malnutrition 
  3. Diarrhoea
  4. Vomiting

Neuropathological Changes in Korsakoff Psychosis

  1. Neuronal loss
  2. Gliosis
  3. Microhaemorrhages

Location of Neuropathological Changes 

  1. Periventricular
  2. Thalamus
  3. Mamillary bodies

Lesions causing Organic Amnestic Syndrome

Organic Amnesia results from lesions in the medial temporal lobe and medial thalamus. Medial temporal lobe lesions cause pure amnesia without impairments in other cognitive domains. 

About the Author

The author is a consultant psychiatrist at the department of psychiatry, Mercy Teaching Hospital Peshawar, and a member of the faculty at the department of psychiatry and behavioural sciences, Peshawar Medical College, Peshawar, 25000, KP, Pakistan. Email: dr.waleed@outlook.com 

References

  1. Kopelman MD. The Korsakoff Syndrome. British Journal of Psychiatry. 1995;166(2):154-173. doi:10.1192/bjp.166.2.154
  2. Jung Y-C, Chanraud S, Sullivan EV. Neuroimaging of Wernicke's encephalopathy and Korsakoff's syndrome. Neuropsychol Rev. 2012;22(2):170-180. doi:10.1007/s11065-012-9203-4
  3. Chandrakumar A, Bhardwaj A, Jong GWt. Review of thiamine deficiency disorders: Wernicke encephalopathy and Korsakoff psychosis. Journal of Basic and Clinical Physiology and Pharmacology. 2019;30(2):153-162. doi:doi:10.1515/jbcpp-2018-0075



Labels:

Comments

Post a Comment

Your Thoughts?

Popular posts from this blog

ADVOKATE: A Mnemonic Tool for the Assessment of Eyewitness Evidence

By
ADVOKATE: A Mnemonic Tool for Assessment of Eyewitness Evidence A tool for assessing eyewitness  ADVOKATE is a tool designed to assess eyewitness evidence and how much it is reliable. It requires the user to respond to several statements/questions. Forensic psychologists, police or investigative officer can do it. The mnemonic ADVOKATE stands for: A = amount of time under observation (event and act) D = distance from suspect V = visibility (night-day, lighting) O = obstruction to the view of the witness K = known or seen before when and where (suspect) A = any special reason for remembering the subject T = time-lapse (how long has it been since witness saw suspect) E = error or material discrepancy between the description given first or any subsequent accounts by a witness.  Working with suspects (college.police.uk)
Post a Comment
Read more

ICD-11 Criteria for Anorexia Nervosa (6B80)

By
ICD-11 Criteria for Anorexia Nervosa (6B80) Anorexia Nervosa is characterised by significantly low body weight for the individual’s height, age and developmental stage that is not due to another health condition or to the unavailability of food. A commonly used threshold is body mass index (BMI) less than 18.5 kg/m2 in adults and BMI-for-age under 5th percentile in children and adolescents. Rapid weight loss (e.g. more than 20% of total body weight within 6 months) may replace the low body weight guideline as long as other diagnostic requirements are met. Children and adolescents may exhibit failure to gain weight as expected based on the individual developmental trajectory rather than weight loss. Low body weight is accompanied by a persistent pattern of behaviours to prevent restoration of normal weight, which may include behaviours aimed at reducing energy intake (restricted eating), purging behaviours (e.g. self-induced vomiting, misuse of laxatives), and behaviours aimed at incr
Post a Comment
Read more

ICD-11 Criteria for Schizophrenia (6A20 )

By
ICD-11 Criteria for Schizophrenia (6A20 ) Schizophrenia is characterised by disturbances in multiple mental modalities, including thinking (e.g., delusions, disorganisation in the form of thought), perception (e.g., hallucinations), self-experience (e.g., the experience that one's feelings, impulses, thoughts, or behaviour are under the control of an external force), cognition (e.g., impaired attention, verbal memory, and social cognition), volition (e.g., loss of motivation), affect (e.g., blunted emotional expression), and behaviour (e.g., behaviour that appears bizarre or purposeless, unpredictable or inappropriate emotional responses that interfere with the organisation of behaviour). Psychomotor disturbances, including catatonia, may be present. Persistent delusions, persistent hallucinations, thought disorder, and experiences of influence, passivity, or control are considered core symptoms. Symptoms must have persisted for at least one month in order for a diagnosis of schi
Post a Comment
Read more