N-methyl-d-aspartate receptor (NMDA-R) autoantibodies have
been reported in people with acute psychosis. We hypothesised that their
presence may be implicated in the aetiology of treatment-refractory
psychosis. We sought to ascertain the point prevalence of NMDA-R antibody
positivity in patients referred to services for treatment-refractory
psychosis. We found that 3 (7.0%) of 43 individuals had low positive NMDA-R
antibody titres. This suggests that NMDA-R autoantibodies are unlikely to
account for a large proportion of treatment-refractory psychosis.