A Case of Valproic Acid-Associated Encephalopathy without Hyperammonemia

Yıl 2019, Cilt: 6 Sayı: 3, 160 - 162, 31.12.2019

MAHMUT BİLAL Çaman , Ayşe Özlem Akgün Semai Bek , Gülnihal Kutlu

Öz

   Valproic acid is a branched-chain carboxylic acid construct used as an
antiepileptic agent. Side effects can be listed as nausea, vomiting, alopecia,
weight gain, asymptomatic increase in liver function tests, fulminant hepatitis,
sedation, ataxia, tremor, pancreatitis, cardiac arrhythmia, thrombocytopenia,
hyperammonemia and encephalopathy. Valproate-associated encephalopathy is often
characterized by impairment in change of consciousness, apathy, irritability,
confusion, and impaired liver function. This table is accompanied with a high
level of ammonia in the blood. Rarely, encephalopathy may occur without
hyperammonemia and irrespective of serum valproate level. Typical clinical
findings in this case report were supported by EEG records and serum ammonia
level was found to be normal in our patient. Valproate Encephalopathy without
Hyperammonemia was diagnosed. Clinical improvement after cessation of valproate
treatment was also demonstrated by EEG findings and the diagnosis was
supported.

Anahtar Kelimeler

Encephalopathy, Epilepsy, Non-hyperammonemia, Valproic Acid

Hiperammonemi Olmaksızın Valproik Asit ile İlişkili Ensefalopati Olgusu

Öz

Valproik asit antiepileptik ajan olarak
kullanılan dallı zincirli karboksilik asit yapısında bir ajandır.  Yan etkileri; bulantı, kusma, alopesi, kilo
alımı, asemptomatik olarak karaciğer fonksiyon testlerinde artış, fulminan
hepatit, sedasyon, ataksi, tremor, pankreatit, kardiyak aritmi, trombositopeni,
hiperammonemi ve ensefalopati tablosu olarak sıralanabilir. Valproat ile
ilişkili ensefalopati sıklıkla bilinç durumunda bozulma, apati, sinirlilik,
konfüzyon, karaciğer fonksiyonlarında bozulma ile karakterize bir tablodur. Bu
tabloya kan amonyak düzeyinde yükseklik sıklıkla eşlik eder. Daha nadir olarak
ise hiperammonemi görülmeden ve serum valproat düzeyine bağlı olmaksızın da
ensefalopati tablosu ortaya çıkabilir. Bildirmiş olduğumuz bu olguda tipik
klinik bulgular; EEG kayıtları ile desteklenmiş, hastamızda serum amonyak
düzeyi normal bulunmuştur ve Hiperammonemi olmaksızın Valproat Ensefalopatisi
tanısına ulaşılmıştır. Sonrasında valproat tedavisinin kesilmesinin ardından
görülen klinik iyileşme, yine EEG bulgularıyla da ortaya konmuş, tanı
desteklenmiştir.

Anahtar Kelimeler

Encephalopathy, Epilepsy, Non-hyperammonemia, Valproic acid

Kaynakça

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