Turcato Marlene de Fátima, Fernandes Regina Maria França, Wichert-Ana Lauro, Funayama Carolina Araújo Rodrigues
Departamento de Neurologia, Psiquiatria e Psicologia Médica, Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, Ribeirão Preto, SP, Brasil.
Arq Neuropsiquiatr. 2005 Jun;63(2A):364-6. doi: 10.1590/s0004-282x2005000200034.
Valproic acid has been widely used for the treatment of epilepsy. Although it is usually well tolerated, it has been associated with some side effects. A poor studied side effect is the hyperammonemia, which independs from the drug hepatotoxic action. The hyperammonemia may occurs just after the beginning or during the treatment and is characterized by vomiting, progressive impairment of consciousness, focal neurologic signs and increased seizure frequency. We report boy a 6 year-old boy who presented with hyperammonemia during the use of valproic acid within the therapeutic range. Complementary investigation was negative for aminoacidopathy, organic acidemia and urea cycle disorders. The hypothesis of secondary effect to the valproic acid was reinforced by the normalization of ammonia levels after drug withdrawal. The pathogenesis of valproate-induced hyperammonemia have been discussed. We conclude that routine monitoring of ammonia blood concentration are strongly recommended in patients under valproic acid treatment.
丙戊酸已被广泛用于治疗癫痫。尽管它通常耐受性良好，但也会出现一些副作用。一个研究较少的副作用是高氨血症，它与药物的肝毒性作用无关。高氨血症可能在治疗开始后或治疗期间出现，其特征为呕吐、意识进行性障碍、局灶性神经体征和癫痫发作频率增加。我们报告了一名6岁男孩，他在使用治疗范围内的丙戊酸期间出现了高氨血症。氨基酸病、有机酸血症和尿素循环障碍的补充检查均为阴性。停药后氨水平恢复正常，这进一步支持了丙戊酸继发效应的假说。本文讨论了丙戊酸诱导高氨血症的发病机制。我们得出结论，强烈建议对接受丙戊酸治疗的患者进行常规血氨浓度监测。
