Effectiveness of Pallidal Stimulation for Dystonic Storm and Subsequent Ssevere Posterior Reversible Encephalopathy Syndrome in a Patient with GNAO1 Variant.

GNAO1 variant affects primarily the brain and neurodevelopment, leading to a range of motor disorders including seizures beginning in infancy and involuntary movements such as dyskinesia and dystonia. Our patient, a 15-year-old Japanese female, began exhibiting involuntary movements at age 4. A de novo missense mutation (NM_020988.3: c.228C>G, NP_066268.1: p.(Asn76Lys)) in the GNAO1 gene was identified when the patient was 15, and during the same year she developed influenza pneumonia, accompanied by dystonic storm. She required intensive care with mechanical ventilation and underwent a tracheostomy. She also developed posterior reversible encephalopathy syndrome. Globus pallidal stimulation was administered, leading to an improvement in the dystonic storm. Early consideration of globus pallidal stimulation is recommended when treating difficult-to-manage dystonic storms.