ABSTRACT

Background: Abnormal plasma levels of free amino acids may predict the severity in patients with drug resistant epilepsy (PRE), having probability to affect their therapeutic approach.

Objectives:We aimed to illuminate the effect of plasma free amino acids (PFAAs) profiles on the etiology of patients with PRE and their contribution on the frequencies of epileptic fits.

Patients and Methods:We collected clinical and metabolomic data of 90 subjects; 45 of them were PRE patients, and other 45 age and sex matched healthy controls. Quantitative measurements of PFAAs profiles using SykamAutomatic Amino Acid Analyzer S433, in addition to fasting blood sugar, liver function tests, kidney function tests and lipid profile also, were determined.

Results: The plasma levels of glutamate, glycine and Gamma amino butyric acid(GABA) plasma levels were significantly increased in PRE group compared to controls (p˂0.0001),their plasma levels also showed significant increase with increased frequency of epileptic fits. Plasma leucine, phenylalanine, aspartate ,ornithine, citrulline, serine and alanine levels (p˂0.0001) were significantly increased in PRE group in relation to healthy controls. Interestingly, on the other hand, histidine, isoleucine, lysine, threonine and the amino acid derivative taurine levels were significantly decreased in PRE patients compared to healthy controls.

Conclusion:Few biomarkers of PRE are available to find the severity and rate of progressionof PRE. The present study showed that altered plasma amino acids and their derivatives may be candidate markers for PRE, help explaining its pathogenesis, and for further researches concerning normalization of the disturbed amino acid/s or its derivative/s (GABA and taurine) in managing PRE patients.

Keywords:Aminogram; Plasma free amino acid profile; Pharmacoresistant epilepsy, amino acids. Abbreviations:Anti-epileptic drugs (AEDs), Branched-chain amino acids (BCAAs), Plasma free amino acids (PFAAs),Pharmaco-resistant epilepsy (PRE).