Study of immunotherapy in antibody positive psychosis: feasibility and acceptability (SINAPPS1)

Abstract

Antibodies against N-Methyl D-Aspartate Receptor (NMDAR) and other neuronal cell surface targets are recognised associations of immunotherapy-responsive autoimmune encephalitis. Initially patients present with symptoms of behavioural change and psychosis, often subsequently developing seizures and cognitive impairment, rapidly progressing over a few weeks to develop a life threatening combination of autonomic instability and loss of consciousness1 There is in vitro and in vivo evidence that these antibodies are pathogenic and directly cause encephalitis. Although never formally demonstrated in a controlled trial, open label clinical studies show that patients receiving immunotherapy, such as intravenous immunoglobulins (IVIG) or plasma exchange (PLEX) with or without corticosteroids, have better recovery and reduced relapse rates. Therefore clinical consensus guidelines recommend immunotherapy is given as soon as possible after diagnosis2.