Author Response: Clinical, Neuroimmunologic, and CSF Investigations in First Episode Psychosis

We appreciate the interest in our research.1 According to Pollak and colleagues,2 criteria of possible autoimmune psychosis (AP) are fulfilled if a patient has abrupt onset psychotic symptoms with at least one of the following: the presence of a tumor, movement disorder (dyskinesias, catatonia), adverse response to antipsychotics, “severe or disproportionate” cognitive dysfunction, decreased level of consciousness, unexplained seizures, and significant autonomic dysfunction.2 Fulfilment of these criteria should lead to additional tests such as EEG, MRI, and serum or CSF investigations. In our series of 105 patients with first episode of psychosis (FEP), 20% fulfilled these criteria but never developed AP.1 We confirm that 2 of 3 patients with anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis presenting with FEP did not fulfill any of these criteria, including catatonia, which is a complex syndrome with its own set of 12 criteria that include echolalia.3 Thus, catatonia and echolalia should not be used as interchangeable terms.