Diagnosis of Aicardi‐Goutières syndrome in adults: A case series

Introduction: Aicardi-Goutieres syndrome (AGS) is a genetic disease presenting with early-onset encephalopathy, generalized dystonia, spasticity, and cognitive disability. Diagnosis may be difficult in adults, as the clinical course seems static from infancy. Methods: AGS patients from an adult movement disorders outpatient clinic were retrospectively analyzed. Results: A total of 5 patients and 1 asymptomatic carrier from 3 different families were identified. All had a homozygous c.529G>A,p.A177T mutation in exon 7 of the RNASEH2B gene. Two patients had neonatal-onset AGS, 2 had later onset forms, and 1 was slightly symptomatic. All were diagnosed in adulthood after chilblains, and basal ganglia calcifications were identified on computed tomography scans. Discussion: AGS patients have marked phenotypic variability regarding psychomotor development and morbidity. The present series included 1 asymptomatic carrier and 1 slightly symptomatic patient, both with homozygous RNASEH2B mutations. Chilblains and basal ganglia calcifications identified on computed tomography scan (but not on magnetic resonance imaging) are important clues for late diagnosis.