Aicardi–Goutières syndrome presenting atypically as a sub-acute leukoencephalopathy

Aicardi–Goutières syndrome is an autosomal recessive encephalopathy characterised by acquired microcephaly, basal ganglia calcifications, leukodystrophy, cerebral atrophy, chronic cerebrospinal lymphocytosis, and raised titres of interferon alpha in the cerebrospinal fluid. The disease onset is generally within the first months of life. We here report a case of Aicardi–Goutières syndrome presenting atypically as a sub-acute leukoencephalopathy following satisfactory psychomotor development up to the age of 16 months. This case highlights the importance of considering Aicardi–Goutières syndrome in the differential diagnosis of an unexplained leukoencephalopathy and the possibility of later onset of the disease.