ABSTRACT
This article reported the clinical features of a rare patient with anti-metabotropic glutamate receptor 5 （mGluR5） encephalitis with mental disorders as the initial symptom， so as to provide references for clinical diagnosis and treatment. The patient was a 38-year-old male， developed pharyngeal pain as prodromal symptoms， and the main clinical manifestations included rapidly progressive memory loss， anxiety and depression， and psychomotor excitement symptoms including irritability and impulsive behaviors. The disease had a progressive deterioration. In the most severe state， the patient became unconscious in a shallow coma， with further cognitive decline， hallucinations and delusions， and lack of self-awareness. Both cerebrospinal fluid and serum anti-mGluR5 antibody were strongly positive （1∶100）. After two sessions of hormone shock therapy， the patient showed significantly improvement in consciousness， cognitive， emotional and psychiatric dimensions.