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Hyperammonemia in idiopathic epileptic seizure
Kensuke Nakamura1, Kiyomi Yamane, Kazuaki Shinohara
1Department of Emergency and Critical Care Medicine, The University of Tokyo Hospital, Tokyo 113-8655, Japan.
The American Journal of Emergency Medicine
|September 7, 2013
Summary
Idiopathic epileptic seizures can cause significant hyperammonemia (high ammonia levels), linked to acidosis. This suggests ammonia production in red blood cells contributes, similar to other emergency conditions.
Area of Science:
- Neurology
- Biochemistry
Background:
- Hyperammonemia is observed in patients with convulsions, but the exact mechanisms are not fully understood.
- While extensive muscle contractions are implicated, ammonia production by red blood cells due to acidosis in emergency conditions is also recognized.
Purpose of the Study:
- To investigate the occurrence and potential causes of hyperammonemia in patients with idiopathic epileptic seizures.
- To explore the relationship between ammonia levels, acidosis, and epileptic seizures.
Main Methods:
- Retrospective analysis of emergency medical cases diagnosed with idiopathic epileptic seizure or epilepsy due to cerebrovascular disorder.
- Exclusion of patients with specific conditions like hepatic encephalopathy, metabolic disorders, alcohol consumption, tumors, or those on valproic acid.
Main Results:
- Elevated ammonia levels (>35 μmol/L) were found in 22 out of 52 analyzed cases, with a maximum level of 506 μmol/L.
- A strong negative correlation was observed between ammonia levels and pH (r = 0.838) and base excess (BE) (r = 0.863), indicating significant acidosis.
Conclusions:
- Idiopathic epileptic seizures are associated with significant hyperammonemia and acidosis.
- The findings suggest that acidosis-induced ammonia production in red blood cells plays a role in hyperammonemia during epileptic seizures, beyond muscle contractions.
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