Reversible parkinsonism and hyperammonemia associated with portal vein thrombosis

Acta Neurol Scand. 2001 Mar;103(3):198-200. doi: 10.1034/j.1600-0404.2001.103003198.x.


Portal-systemic encephalopathy may be seen with hyperammonemia that complicates chronic liver disease. We report an unusual case of reversible parkinsonism associated with hyperammonemia and portal vein thrombosis. An active 90-year-old male developed motor slowing and resting hand tremor over 6 months. Examination showed asterixis, bradykinesia, cogwheel rigidity, rest tremor, and a parkinsonian gait. Serum venous ammonia was elevated at 145 microM. The next day, the patient became comatose and serum ammonia was 178 microM. With lactulose therapy, serum ammonia level normalized and examination showed only minimal parkinsonism after 1 week. An abdominal CT scan identified portal vein thrombosis with porto-systemic shunting that reversed after 7 months of treatment. Examination 2 years later showed no signs of parkinsonism. Parkinsonism can dominate the clinical picture of patients with hyperammonemia before the onset of encephalopathy.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Coma / etiology
  • Humans
  • Hyperammonemia / etiology*
  • Hyperammonemia / pathology
  • Male
  • Parkinsonian Disorders / etiology*
  • Parkinsonian Disorders / pathology
  • Parkinsonian Disorders / therapy
  • Portal Vein / pathology*
  • Portasystemic Shunt, Surgical
  • Thrombosis / complications*
  • Thrombosis / pathology
  • Tomography, X-Ray Computed
  • Treatment Outcome