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Hyperammonemia and hepatic status during valproate therapy
Rachna Agarwal1, Sangeeta Sharma, Neelam Chhillar
1Department of Neurochemistry, Institute of Human Behaviour and Allied Sciences, Dilshad Garden, Delhi, 110095 India ; E-150, Sector- 21, Noida, 201301 UP India.
Indian Journal of Clinical Biochemistry : IJCB
|October 30, 2012
Summary
Elevated ammonia levels correlate with valproate toxicity in epileptic patients. Regular monitoring of serum ammonia and liver enzymes aids in early diagnosis of valproate toxicity.
Area of Science:
- Neurology
- Clinical Chemistry
Background:
- Valproate is a common antiepileptic drug, but its toxicity can lead to serious complications.
- Valproate toxicity is associated with elevated serum valproate levels, but early biochemical markers are crucial for timely intervention.
Purpose of the Study:
- To investigate the correlation between serum ammonia levels and valproate levels in epileptic patients with valproate toxicity.
- To determine if liver enzymes and ammonia levels can serve as biochemical markers for valproate toxicity.
Main Methods:
- A case-control study involving 100 epileptic patients with valproate toxicity and 100 controls.
- Measurement of serum valproate, ammonia, and liver enzymes in all subjects.
Main Results:
- Patients with valproate toxicity had significantly higher serum ammonia levels compared to controls (86.37 ± 39.90 µg/dL vs. 68.73 ± 30.07 µg/dL).
- Only 37% of toxic patients had serum valproate levels > 120 mg/dL, suggesting ammonia levels may be a more sensitive early indicator.
- Age < 30 years and serum ammonia > 69 μg/dL were identified as risk factors for valproate toxicity.
Conclusions:
- Serum ammonia levels are elevated in patients with valproate toxicity.
- Regular monitoring of serum ammonia and liver enzymes is recommended for early diagnosis and management of valproate toxicity in patients on long-term valproate therapy.
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