Portal-systemic encephalopathy suggesting elderly onset epilepsy

Abstract

Abstract:In elderly onset epilepsy, focal impaired awareness seizures are often observed, small doses of antiepileptic drugs are effective, and stroke is the most common cause.　In addition, the prevalence of elderly onset epilepsy is estimated to be about 1%.　Non-cirrhotic portal-systemic encephalopathy often develops in middle-aged and elderly people.　It presents with various symptoms, but rarely with epileptic seizures.　We experienced a case of portal-systemic encephalopathy with epileptic seizures in an elderly patient.　A 79-year-old woman presented with epileptic seizures.　The symptom improved rapidly with the administration of antiepileptic drugs, but hyperammonemia was present.　Urease-producing Klebsiella oxytoca was detected in urine culture, and trimethoprim-sulfamethoxazole combination was administered, but hyperammonemia persisted.　Electroencephalography showed a persistent generalized slow wave.　Head MRI showed a high-intensity area in the bilateral globus pallidus on T1-weighted images, and abdominal CT showed a portal-systemic shunt that branched from the portal vein and flowed directly into the inferior vena cava.　The patient was diagnosed with portal-systemic encephalopathy and the ammonia level was normalized by conservative treatment.　When treating patients with the first epileptic seizure occurring at older ages, it is necessary to distinguish between elderly onset epilepsy and other diseases that cause epileptic seizures.　In Japan, a super-aging society, understanding elderly onset epilepsy is important.