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Conditions Covered
• Wernicke’s Encephalopathy
• Hepatic Encephalopathy
• Toxic & Metabolic Encephalopathy
• Uremic Encephalopathy
• Hypertensive Encephalopathy
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Encephalopathy = Global brain dysfunction
Encephalitis = Brain inflammation
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Wernicke’s Encephalopathy
Acute, reversible encephalopathy caused by thiamine (B1) deficiency.
Key Differentiator: Confusion + Ataxia + Ophthalmoplegia in a malnourished or alcoholic patient.
Essentials:
• Cause: Thiamine (B1) deficiency
• Population: Alcoholics, malnourished, bariatric surgery patients
• Treatment: IV thiamine BEFORE glucose
• Complication: Can progress to Korsakoff syndrome (irreversible)
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Hepatic Encephalopathy
Neuropsychiatric dysfunction due to ammonia buildup in liver failure.
Key Differentiator: Asterixis in a patient with known or suspected liver dysfunction.
Essentials:
• Cause: Ammonia accumulation in liver failure
• Triggers: GI bleed, infection, sedatives
• Treatment: Lactulose first-line, rifaximin second-line
• Labs: Ammonia often elevated but not diagnostic alone
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Toxic & Metabolic Encephalopathy
Diffuse cerebral dysfunction caused by systemic illness or metabolic/toxic imbalance.
Key Differentiator: EEG showing generalized background slowing in altered mental status.
Essentials:
• Common causes: Hypoglycemia, sepsis, hypoxia, toxins
• Sx: Myoclonus, hyperreflexia, fluctuating mental status
• Diagnostics: CMP, ABG, tox screen, EEG
• Treatment: Fix the underlying issue (O2, glucose, electrolytes)
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Uremic Encephalopathy
Encephalopathy due to accumulation of toxins in advanced renal failure.
Key Differentiator: BUN >100 + altered mental status in a patient with ESRD.
Essentials:
• Cause: Toxin buildup in renal failure
• Sx: Asterixis, myoclonus, seizures
• Treatment: Urgent dialysis
• EEG: Triphasic waves possible but not specific
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Hypertensive Encephalopathy
Cerebral dysfunction from critically elevated blood pressure causing brain edema.
Key Differentiator: Severely elevated BP (>180/120) + AMS + papilledema
Essentials:
• Cause: Cerebral edema from hypertensive emergency
• Sx: Headache, vomiting, seizures
• Imaging: CT to rule out stroke
• Treatment: Gradual BP reduction (nicardipine, labetalol); avoid rapid drops
1. Classic triad of Wernicke’s encephalopathy?
2. First-line treatment for hepatic encephalopathy?
3. EEG hallmark of metabolic encephalopathy?
4. What triggers should you always look for in hepatic encephalopathy?
5. What’s the definitive treatment for uremic encephalopathy?
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PANCE-Style
Which of the following is a hallmark finding in hepatic encephalopathy?
A. Papilledema
B. Myoclonus
C. Asterixis
D. Ophthalmoplegia
A 59-year-old man with end-stage renal disease (ESRD) presents to the emergency department with progressive confusion and drowsiness over the past two days. According to his family, he has been increasingly forgetful, slow to respond, and intermittently jerking his arms during rest.
On physical exam, he is alert but disoriented to time and place. When asked to extend his arms and dorsiflex his wrists, you observe brief, involuntary flapping movements. Additionally, he exhibits occasional sudden, involuntary twitches of his upper extremities.
Laboratory results:
• BUN: 108 mg/dL
• Creatinine: 11.4 mg/dL
• Potassium: 6.1 mEq/L
• Calcium: 7.4 mg/dL
• Bicarbonate: 16 mEq/L
• pH: 7.30
Which of the following is the most appropriate next step in management?
A. Administer intravenous thiamine
B. Initiate treatment with lactulose
C. Begin empiric broad-spectrum antibiotics
D. Initiate emergent hemodialysis
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A 62-year-old man with a history of cirrhosis presents with confusion, slurred speech, and altered sleep patterns. His wife reports he recently had a bout of constipation and has not taken his usual medications for several days. On exam, he is oriented to person only and demonstrates a flapping movement when asked to hold his arms out and extend his wrists. Vitals are stable.
Labs:
• AST: 78 U/L
• ALT: 62 U/L
• Total bilirubin: 3.1 mg/dL
• Ammonia: 86 µmol/L
• INR: 1.7
Which of the following is the most appropriate initial treatment?
A. Rifaximin
B. Intravenous thiamine
C. Emergent dialysis
D. Lactulose
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Which of the following physical findings is most characteristic of hepatic encephalopathy?
A. Papilledema
B. Flapping hand tremor when wrists are extended
C. Pinpoint pupils
D. Babinski sign
Question 2: Level 4 (Clinical Differentiation)
A 70-year-old woman with a history of cirrhosis presents with progressive confusion and lethargy. She is oriented to person only. Physical exam shows non-rhythmic flapping of the hands when her arms are extended. Labs reveal elevated ammonia and mild hyponatremia. Her BUN and creatinine are within normal limits.
Which of the following best supports hepatic encephalopathy over other causes of altered mental status?
A. Normal renal function with elevated BUN
B. Presence of myoclonus and papilledema
C. Elevated ammonia and flapping tremor
D. Triphasic waves on EEG
• D. Triphasic waves on EEG – Incorrect