Isolated Psychiatric Symptoms in Children With Anti-N-Methyl-d Aspartate Receptor Encephalitis

Area of Science:

• Neurology
• Immunology
• Pediatrics

Background:

• Pediatric anti-N-methyl-d-aspartate (NMDA) receptor autoimmune encephalitis (pNMDARE) may initially manifest with isolated psychiatric symptoms.
• Understanding the prevalence and diagnostic characteristics of these initial symptoms is crucial for early detection and treatment.

Purpose of the Study:

• To determine the prevalence of isolated psychiatric symptoms in pediatric anti-NMDA receptor autoimmune encephalitis (pNMDARE).
• To assess the utility of initial neurodiagnostic tests (MRI, EEG, CSF analysis) in children presenting with isolated psychiatric symptoms and pNMDARE.

Main Methods:

• A multicenter retrospective cohort study involving children under 18 diagnosed with pNMDARE.
• Descriptive statistics were used to analyze the prevalence and characteristics of isolated psychiatric symptoms and initial neurodiagnostic findings.

Main Results:

• Out of 249 children, 12 (5%) presented with only psychiatric symptoms.
• Of these 12 children, 11 (92%) had at least one abnormal neurodiagnostic test, including EEG (67%), MRI (50%), and CSF pleocytosis (42%).
• One patient with normal initial tests and low positive CSF NMDA antibody titer improved without immunotherapy.

Conclusions:

• Isolated psychiatric symptoms are an uncommon initial presentation of pNMDARE.
• The majority of children with pNMDARE and isolated psychiatric symptoms exhibit abnormalities in initial neurodiagnostic tests.
• Immunotherapy may be delayed in cases of isolated psychiatric symptoms with normal neurodiagnostic findings pending confirmatory antibody testing.