Paroxysmal speech disorder as the initial symptom in a young adult with anti-N-methyl-D-aspartate receptor encephalitis: A case report

BACKGROUND: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a treatable but frequently misdiagnosed autoimmune disease. Speech dysfunction, as one of the common manifestations of anti-NMDAR encephalitis, is usually reported as a symptom secondary to psychiatric symptoms or seizures rather than the initial symptom in a paroxysmal form. We report a case of anti-NMDAR encephalitis with paroxysmal speech disorder as a rare initial manifestation, and hope that it will contribute to the literature. CASE SUMMARY: A 39-year-old man with anti-NMDAR encephalitis initially presented with paroxysmal nonfluent aphasia and was misdiagnosed with a transient ischemic attack and cerebral infarction successively. The patient subsequently presented with seizures, but no abnormalities were found on brain magnetic resonance imaging or electroencephalogram. Cerebrospinal fluid (CSF) analysis revealed mild pleocytosis and increased protein levels. Anti-NMDAR antibodies in serum and CSF were detected for a conclusive diagnosis. After immunotherapy, the patient made a full recovery. CONCLUSION: This case suggests that paroxysmal speech disorder may be the presenting symptom of anti-NMDAR encephalitis in a young patient.