Differential Diagnosis for Elevated Bilirubin and Neurological Symptoms in a Post-Transplant Patient

• Single Most Likely Diagnosis:

  • Hyperammonemia: Despite normal liver enzymes, hyperammonemia can occur, especially in a post-transplant patient. The symptoms of flaps (asterixis), sleep-wake cycle reversal, and drowsiness are classic for hepatic encephalopathy, which can be caused by elevated ammonia levels. Hyperammonemia can lead to cerebral edema and is a medical emergency.

• Other Likely Diagnoses:

  • Graft Dysfunction or Rejection: In a post-transplant patient, graft dysfunction or rejection could lead to elevated bilirubin and potentially affect the patient's neurological status indirectly through mechanisms like hyperammonemia or other metabolic disturbances.
  • Infection or Sepsis: Post-transplant patients are immunocompromised and at higher risk for infections, which can cause a wide range of symptoms including altered mental status and elevated bilirubin due to systemic inflammation.
  • Drug Toxicity: Certain medications, especially those used in the management of post-transplant patients (e.g., immunosuppressants), can have hepatotoxic effects or contribute to neurological symptoms.

• Do Not Miss Diagnoses:

  • Cerebral Edema: A potentially life-threatening complication that can occur in the setting of acute liver failure or severe hyperammonemia. Early recognition and treatment are crucial.
  • Posterior Reversible Encephalopathy Syndrome (PRES): Associated with hypertension, immunosuppressive drugs, and renal failure, PRES can cause altered mental status and seizures. It is reversible with prompt treatment.
  • Central Pontine Myelinolysis (CPM): Although rare, CPM can occur, especially with rapid correction of sodium levels, leading to severe and potentially irreversible neurological damage.

• Rare Diagnoses:

  • Wilson's Disease: An inherited disorder that leads to copper accumulation in the liver and brain. Although rare, it could present with liver dysfunction and neurological symptoms.
  • Budd-Chiari Syndrome: Thrombosis of the hepatic veins can cause liver dysfunction and potentially lead to neurological symptoms through mechanisms like hyperammonemia, though this would be less common.
  • Mitochondrial Disorders: Certain mitochondrial disorders can affect both the liver and the brain, leading to a wide range of symptoms including those described. However, these are relatively rare and would typically have a more chronic presentation.