Altered Sensorium Differential Diagnosis

The differential diagnosis for altered sensorium is broad and can be categorized for a more structured approach. Altered sensorium refers to an abnormality in an individual's level of consciousness or alertness, which can range from mild confusion to coma. The causes can be diverse, including metabolic, infectious, structural, and psychiatric conditions.

• Single Most Likely Diagnosis
  • Hypoglycemia: Given its prevalence and the critical nature of timely intervention, hypoglycemia is often considered a single most likely diagnosis in many clinical scenarios, especially in diabetic patients. It can cause confusion, altered mental status, and even loss of consciousness if not promptly treated.
• Other Likely Diagnoses
  • Urinary Tract Infection (UTI): Especially in the elderly, UTIs can present with altered sensorium as the primary symptom, without the typical symptoms of dysuria or frequency.
  • Pneumonia: Severe infections like pneumonia can lead to confusion and altered mental status, particularly in older adults or those with compromised immune systems.
  • Medication Side Effects: Many medications, including sedatives, anticholinergics, and certain antidepressants, can cause altered sensorium as a side effect.
  • Electrolyte Imbalances: Conditions such as hyponatremia, hypernatremia, hypercalcemia, and hypocalcemia can lead to altered mental status.
• Do Not Miss Diagnoses
  • Stroke or Transient Ischemic Attack (TIA): Although often presenting with focal neurological deficits, some strokes (especially those involving the brainstem or bilateral hemispheres) can cause altered sensorium without obvious focal signs.
  • Status Epilepticus: Prolonged or recurrent seizures without full recovery of consciousness between them can present as altered sensorium.
  • Meningitis or Encephalitis: Infections of the meninges or brain can cause severe and potentially life-threatening altered sensorium.
  • Subarachnoid Hemorrhage: A sudden, severe headache with altered sensorium could indicate a subarachnoid hemorrhage, which is a medical emergency.
• Rare Diagnoses
  • Hashimoto's Encephalopathy: A rare condition associated with autoimmune thyroiditis, characterized by altered sensorium, seizures, and stroke-like symptoms.
  • Whipple's Disease: A systemic bacterial infection that can cause altered sensorium, among other symptoms like weight loss, diarrhea, and arthralgias.
  • Creutzfeldt-Jakob Disease: A rare, degenerative, fatal brain disorder that can present with rapidly progressive dementia and altered sensorium.

Each of these diagnoses requires a thorough clinical evaluation, including history, physical examination, and appropriate laboratory and imaging tests to determine the underlying cause of the altered sensorium.