Head circumferences of patients with Dravet syndrome show growth slowdown.

The measurement of head circumference (HC) represents a useful and reliable tool to monitor brain growth. Many genetic conditions are associated with an abnormal pattern of head growth, but no specific pattern has been described in Dravet Syndrome (DS). To investigate the head growth trajectories in a pediatric population with DS, a retrospective analysis of medical records of patients with DS was performed in 2 epilepsy centers. Quantitative data were compared with z-score growth curve of standard population, and an independent samples t-test was performed using 6-month ranges. A total of 137 subjects aged less than 18 years were included, with a total of 529 HC values and a mean of 3.9 measures per patient. From birth until 24 months of life, HC values were almost equally distributed around the mean trajectory of the reference population from each side of the curve. This trend line deflects from the mean curve after 24 months showing a head growth slowdown reaching a statistical significance (p < .05) from 48 months for males and 60 for females. Future prospective studies are needed to assess factors that can impact head growth and explore possible phenotype-genotype correlation with HC.