Significance of the laboratory findings and therapeutic drug-monitoring intreatment of children with valproic acid

Background. The scope of laboratory diagnostic measures necessary in the ca se of children receiving anti-epileptic valproate treatment has been contro versially discussed. The aim of the present study was to evaluate possible interconnections between valproate treatment, changes to the clinico-chemic al parameters as well as the blood level of valproic acid and valproate met abolites in children. Methods and Patients. 69 children and adolescents (ages: 6 months to 16 yea rs) were treated regularly with valproic acid (mono- or polytherapy). Valpr oic acid and valproate metabolites were determined in serum using capillary gas chromatography mass spectrometry. Results. Mo clinically relevant interconnections between the forms of thera py (mono- or polytherapy), the valproic acid dosage,the measured valproic a cid and metabolite blood levels, on the one hand,and the clinico-chemical p arameters, on the other, could be determined. Significant correlations only occurred between alanine-amino-transferase and valproic acid as well as so me metabolites (3-keto,4-keto and (E)-3-en-valproate). Hepatotoxic side-eff ects were not seen even in these children. Conclusions. It can be concluded from our results that determination of cli nico-chemical and haematological parameters is only indicated with the corr esponding clinical symptoms even in the case of children over 3 years (just as in adults). This reduces the burden on these children. Further investig ations into extended therapeutic drug-monitoring should be considered for c hildren under three years which also includes some valproate metabolites.