Anton syndrome with bilateral occipital infarct: A case report

Abstract

Anton syndrome results from damage to the visual cortex of the occipital lobes, where the anterior visual pathways remain intact. This damage results in the characteristic triad of cortical blindness, visual anosognosia, and visual confabulation. This case describes an 80-year-old male with a background of renal transplant 7 years prior, admitted to hospital with worsening transplant function, and soon after developed sudden onset cortical blindness. On examination, the patient was found to be in denial of his blindness and showed signs of visual confabulation, both of which pointed toward a diagnosis of Anton syndrome. Radiological investigation with computed tomography (CT) and magnetic resonance imaging (MRI) revealed bilateral ischemic stroke of the occipital lobes, which was later theorized to have occurred due to sirolimus-induced thrombotic microangiopathy (TMA). To the author's knowledge, this is the first case report of sirolimus-induced TMA, bilateral ischemic occipital lobe stroke, and Anton's syndrome, within the same diagnosis. This case highlights that a diagnosis of bilateral occipital stroke with denial of blindness should suggest a diagnosis of Anton syndrome. This report also discusses the importance of differentiating bilateral occipital infarction on CT imaging, from posterior reversible encephalopathy syndrome (PRES), using MRI.