Neuropsychological functioning in children with early-treated phenylketonuria: impact of white matter abnormalities.
Impact of white matter abnormalities (WMAs) on neuropsychological functioning in children with early-treated phenylketonuria (ETPKU) was examined. Children with ETPKU (20 males, 12 females, mean age 11 years 2 months, SD 3 years 6 months) and controls (20 males, 14 females, mean age 10 years 4 months, SD 3 years 1 month) aged 7 to 18 years were assessed using tests of attention, processing speed, memory and learning, executive function, and academic achievement. Those with ETPKU, exhibiting WMAs extending into subcortical/frontal regions (n=14), displayed significant impairments in a number of domains. Children with ETPKU but no WMAs (n=6), or pathology restricted to the posterior periventricular region (n=12), displayed only mild deficits. Concurrent phenylalanine levels correlated weakly with cognitive parameters, whereas lifetime phenylalanine levels were associated with deficits in several cognitive domains. Impairments in children with extensive WMAs are consistent with compromised neural transmission, which is characterized by dysmyelination. However, children with no detectable, or mild WMAs, also displayed cognitive problems, indicating that neuropsychological functioning in children with ETPKU is determined by a complex interaction of biological and environmental factors.
Anderson
Peter J
PJ
Department of Psychology, Royal Children's Hospital, Melbourne, Victoria, Australia. anderson@cryptic.rch.unimelb.edu.au
Wood
Stephen J
SJ
Francis
Dorothy E
DE
Coleman
Lee
L
Warwick
Linda
L
Casanelia
Sue
S
Anderson
Vicki A
VA
Boneh
Avihu
A
D000293:Adolescent; D001288:Attention; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000002:abnormalities* / Q000503:physiopathology; D002648:Child; D005260:Female; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D007858:Learning; D008279:Magnetic Resonance Imaging; D008297:Male; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D010661:Phenylketonurias / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy; D011340:Problem Solving; D011597:Psychomotor Performance; D011932:Reading; D013998:Time Perception