Autistic regression with and without EEG abnormalities followed by favourable outcome

Objectives: To explore the relationship between autistic regression (AR) with and without EEG abnormalities and favourable outcome.

Methods: Follow up data on children with favourable outcome in a series of 534 cases aged below 5 years and diagnosed as ASD.

Results: Cases with regression were 167 (31.8%), usually with persistent ASD, intellectual disabilities and EEG abnormalities. Thirty nine children (7.3%) went off autism and recovered entirely their intellectual and social abilities. Few of them included examples of pharmacologically treated Landau and Kleffner syndrome and other similar complex cases with abnormal EEG. The majority was represented by 36 (6.7%) children, mostly males, with a dysmaturational syndrome: their development was initially normal up to 18 months when an autistic regression occurred accompanied by the appearance of motor and vocal tics. Relational therapies were followed by rapid improvement. By 6 years all children had lost features of ASD and their I.Q. was in most cases between 90 and 110. Convulsions were absent and EEG was normal in all cases except one. In a few of them recovery was spontaneous. Seventeen children were followed after 5 years 6 months: 12 (70%) had ADHD, 10 (56%) persistent tics. Tics were often present in parents and relatives, ASD absent, suggesting a genetic background different from cases with persistent ASD. With one exception all "off autism" children had a previous autistic regression.

Conclusions: In this series "off autism" children had either early onset epilepsy and/or EEG abnormalities or cases of dysmaturational syndrome. Autistic regression was present in almost all.