Day #36 - Acute Confusion

Today we talked about a case of an elderly woman with an acute confusion. In approaching this problem, the history is important to exclude dementia which was sub-clinical for a long period but subsequently becomes obvious to the family.

We looked at a differential for an acute change in level of consciousness and the following general framework is helpful:

1. Drugs/Iatrogenic
2. Infection
   
   • Meningitis (bacterial, viral, TB, other -- e.g. cryptococcal, neurosyphilis)
   • Encephalitis (HSV1/2, HIV, CMV, WNV, Eastern Equine encephalitis, other)
   • Non-CNS infection with delerium
     
3. Metabolic
   
   • Electrolytes (hyper Ca, hypo/hyper Na, hypoglycemia)
   • hypothyroidism. B12/folate not usually acute.
     
4. Structural
   
   • Tumour
   • Bleed (SDH, SAH, ICH)
   • Other mass lesion
   • Epileptogenic focus (post ictal)
   • Stroke syndrome
   • Vasculitis
5. End-organ Failure
   
   • Cirrhosis (encephalopathy)
   • CHF
   • Respiratory -- Hypoxemia/Hypercarbia
   • Renal - Uremia
     

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We then talked a bit about aphasias because the patient had anomia with a non-fluent aphasia and inability to understand.

Aphasias
1-naming-if normal - no aphasia
2-command-

DON'T UNDERSTAND
non fluent, no repeat - global aphasia
non fl - can repeat mixed transcortical
fluent - no repeating - wernikes
- can repeat - trans cortical sensory aphasia
UNDERSTAND
non fl--no repeat - brocas
non fl - can repeat - transcortical motor
fl - no repeat - conductive
fl - repeat - no name - nominal

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We then entertained the possibility of neurosyphilis or a paraneoplastic syndrome such as paraneoplastic limbic encephalitis.

Neurosyphilis can present with a variable presentation.

"Early" <>

• asymptomatic
• meningitis (with cranial nerve palsies)
• meningovascular -- clinical picture of strokes, recurrent. Part of the differential for stroke in the young.
• otic syphilis -- tinnitus, vertigo, hearing loss
• occular syphilis -- uveitis, retinitis, vitritis
  

"Late" >10 years

• General paresis (of the insane):
  P - personality changes
  A - affect changes
  R - reflexes (hyper-reflexia)
  E - Eye (argyll-robertson pupils)
  S - Sensorium - delusions, hallucinations
  I - Intellect
  S - Speech (abnormal)
  
• Tabes dorsalis: sensory loss (dorsal columns), ataxia, bladder dysfunction, "lightning" pains in legs
  

Patients should have a positive RPR (though can be negative) and positive confirmatory test like the TPPA.

CSF should:

1. Have a positive VDRL (specific, but not sensitive)
2. OR Have a lymphocytic pleocytosis (WBC >20) and/or protein >500mg and positive peripheral serologies
   
3. Be suspected in positive CSF FT-ABs is positive