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Hyperammonemia is associated with generalized convulsion.
Youichi Yanagawa1, Kouichirou Nishi, Toshihisa Sakamoto
1Department of Traumatology and Critical Care Medicine, National Defense Medical College, Tokorozawa. yanagawa@ndmc.ac.jp
Internal Medicine (Tokyo, Japan)
|January 8, 2008
Summary
Generalized convulsion (GC) is linked to elevated ammonia levels (hyperammonemia). However, immediate post-convulsion ammonia testing may not diagnose hyperammonemia as the cause.
Area of Science:
- Neurology
- Biochemistry
Background:
- Generalized convulsion (GC) is a critical neurological event.
- Hyperammonemia, elevated ammonia levels in the blood, is a known neurotoxin.
Purpose of the Study:
- To investigate the association between generalized convulsion and hyperammonemia.
- To determine the utility of immediate post-convulsion ammonia measurements.
Main Methods:
- Retrospective analysis of 17 patients presenting with GC.
- Serum biochemistry, including ammonia levels, was analyzed.
- Ammonia levels were re-checked in a subset of patients on hospital day 2.
Main Results:
- All patients with GC exhibited hyperammonemia.
- Common causes of GC included intracranial lesions, endocrine diseases, and epilepsy.
- Ammonia levels decreased by hospital day 2 without specific treatment.
Conclusions:
- Generalized convulsion is associated with hyperammonemia.
- While hyperammonemia can induce seizures, immediate post-GC ammonia levels are not definitive for diagnosing hyperammonemia-induced seizures.
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