Abstract Details

Title Anti-GABA-A Receptor Encephalitis Presenting as Fulminant Hemicerebellitis in a 5-Year-Old Girl

Topic Autoimmune Neurology

Presentation(s) P2 - Poster Session 2 (11:45 AM-12:45 PM)

Poster/Presentation
Number 1-006

Objective To report a child with anti-GABAA receptor encephalitis presenting as fulminant hemicerebellitis without early seizures, an atypical phenotype, and to describe the response to early, aggressive immunotherapy with timely decompression.

Background Fulminant cerebellitis is a rare pediatric emergency; autoimmune etiologies, including anti-GABAAR encephalitis, may present atypically and deteriorate rapidly. Early recognition and timely therapy escalation can be life-saving.

Design/Methods Single-patient case with clinical, radiographic, EEG, CSF cytokine, and antibody data collected during PICU admission.

Results A previously healthy 5-year-old presented with fever, lethargy, and right cerebellar edema effacing the fourth ventricle. Emergent posterior-fossa decompressive craniectomy with C1 laminectomy was performed. CSF showed mild pleocytosis; MRI revealed right cerebellar T2/FLAIR hyperintensity with scattered cortical foci. Empiric high-dose IV methylprednisolone began on day 2 and tocilizumab on day 3. Despite antimicrobials, deterioration with new seizures occurred by day 5. A modified plasma-exchange/IVIG “zipper” and a second tocilizumab dose were given. Rising CSF interleukin-6 and continued clinical decline prompted escalation to daily intrathecal dexamethasone and high-frequency tocilizumab (8 mg/kg q12 h). Treatment led to clinical stabilization and extubation, with falling CSF IL-6 and radiographic improvement on MRI. On day 32, expanded serum/CSF testing detected anti-GABAA receptor antibodies. By day 37, the child showed substantial recovery of language, motor function, and cognition, with mild residual hemineglect at discharge.

Conclusions Anti-GABAA receptor encephalitis can manifest as fulminant hemicerebellitis and progress to brain-stem compression within hours. Early, coordinated management, including posterior-fossa decompression when indicated; escalation beyond steroids/IVIG/PLEX when clinical status, EEG, or neuroimaging worsens despite typical therapy; CSF IL-6–informed intrathecal/targeted therapy; and expanded antibody panels (including anti-GABAA), can stabilize the disease course before antibody confirmation and enable meaningful recovery.

Authors/Disclosures
Kellie E. Krohn PRESENTER	Miss Krohn has nothing to disclose.
Rebecca Luke, DO (Cook Children's)	Dr. Luke has nothing to disclose.
Adrian R. Lacy, MD (Cook Childrens Medical Center)	Dr. Lacy has nothing to disclose.
Sandy Cope-Yokoyama, MD	Dr. Cope-Yokoyama has nothing to disclose.
John Honeycutt, MD	Dr. Honeycutt has nothing to disclose.
Jonathan Santoro, MD (Department of Neurology, Children's Hospital Los Angeles)	Dr. Santoro has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for UCB. Dr. Santoro has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for Cycle Pharma. Dr. Santoro has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Dianthus. Dr. Santoro has received personal compensation in the range of $500-$4,999 for serving as a Consultant for National Down Syndrome Society.
Alfred Balasa, MD	Dr. Balasa has nothing to disclose.

��ɫ��

��ɫ��