Altered perception might be a symptom of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis.

Most patients with N-methyl-D-aspartate receptor (NMDAR) encephalitis initially present with psychiatric symptoms. Although a delayed diagnosis may lead to a poor outcome, psychiatric symptoms that could differentiate anti-NMDAR encephalitis from other psychoses have not been fully investigated. We evaluated two patients with anti-NMDAR encephalitis who were observed by psychiatrists from onset throughout the course of disease. Both patients exhibited disorientation, memory deficits, perceptual disturbances, hallucinations, and mood liability. Among those, altered perceptions were most prominent - in particular, altered time perceptions without disorganization syndrome. The information obtained for these patients may help clinicians differentiate anti-NMDAR encephalitis from other psychoses, e.g., schizophrenia.