Cognitive outcome of classic infantile Pompe patients receiving enzyme therapy

Methods We prospectively assessed cognitive functioning in 10 children with classic infantile Pompe disease who had been treated with ERT since 1999. Until 2004, infants and young children were assessed with the Bayley Scales of Infant Development (BSID-II; number of tests = 23). After 2004, we switched to the Griffiths Mental Developmental Scales (Griffiths; number of tests = 19), expecting it to differentiate better between various domains. Older children were assessed using the Wechsler Intelligence Scales for Children (WISC-III; number of tests = 5). For children with tetraplegia, we used the Raven Colored or Standard Progressive Matrices (number of tests = 3). For those with impaired hearing, we used the Snijders Oomen Nonverbal Intelligence testRevised (SON-R 21⁄2-7, number of tests = 1). In total, 51 tests were performed. Brain imaging was performed in six children.