A Case of Anterograde Amnesia with Bilateral Hippocampus Involvement After Acute Glufosinate Ammonium Intoxication

Abstract

Glufosinate ammonium is a commercial herbicide made from a phosphinic acid derivative of glutamate, which leads to a lethal accumulation of ammonia in plants by inhibiting the activity of glutamine synthetase (1). As the use of glufosinate-ammoniumcontaining herbicides has increased, so too has the incidence of acute intoxication through accidental or purposeful (attempted suicide) ingestion of this herbicide ingestion. The prompt and accurate diagnosis of glufosinate ammonium intoxication is critical from the management perspective. Acute glufosinate ammonium intoxication is associated with various neurological symptoms including loss of consciousness, convulsion, and memory impairment (1-3). New memory formation occurs in the hippocampus, and lesions in the bilateral hippocampus result in an inability to form new memories, a condition known as anterograde amnesia (4, 5). This report describes the case of a patient who presented with anterograde amnesia following the ingestion of a glufosinate-ammonium-containing herbicide in an attempted suicide. The anterograde amnesia was related to a lesion in the hippocampus. The differential diagnosis of hippocampal lesions is discussed.