Progressive Intermittent Hemidystonia, Behavioral Changes and Sleep Disturbances without MRI Changes: Anti-NMDA Receptor Encephalitis in a 3-Year-Old

Background/Purpose: Anti-NMDA receptor encephalitis is a rare autoimmune disease mainly occurring in young women who present most often with acute behavioral change, psychosis, memory and speech problems as well as seizures. Life-threatening symptoms, i.e., loss of consciousness, autonomic dysfunction, and central hypoventilation can evolve and less frequently movement disorders and sleep disturbances are described. Specific EEG patterns are reported.

The clinical presentation in children and adolescents may be different and therefore diagnosis challenging.

Case Report: A 3-year-old girl presented with acute onset and progressive intermittent hemidystonia consisting of distortion of the left side of the face with speech problems, dystonic posturing with uncontrolled movements of the left arm and less often also gait instability. Within days to weeks, she developed considerable mood swings with temper tantrums, compulsive behavior, interrupted sleep and photosensitivity. Cerebral MRI and routine CSF analysis (cell count, protein, lactate, and glucose) revealed no abnormalities. The EEG showed right hemispheric slowing accentuated over the frontal lobe and anterior theta-alpha band rhythms in non-REM sleep. Anti-NMDA-receptor antibodies in serum (1:100) and CSF (1:10) were positive. Intravenous, immunomodulatory treatment was started with high dose methylprednisolone followed by immunoglobulins with complete recovery. Movement disorder resolved first, sleep disturbances and behavioral changes later, and NMDA-receptor antibodies were negative (serum and CSF).

Conclusion: Anti-NMDA-receptor encephalitis should be considered in children and adolescents with acute, fluctuating movement disorders even if unilateral, especially when cerebral MRI is normal. Specific EEG patterns can be helpful for diagnosis. CSF pleocytosis is not mandatory.

Publication History

Article published online:
28 October 2021