Benefits of normalizing plasma phenylalanine: impact on behaviour and health. A case report.
An elderly man with mental retardation who had never received dietary treatment for his phenylketonuria was placed on a phenylalanine-restricted diet. Social skills and walking gait improved and a new interest in the objects in his environment developed spontaneously. A 2-year analysis of diet, blood plasma phenylalanine levels and behavioural state indicated that small differences in phenylalanine intake impacted his well-being. Of significant note, leg tremor and spasm that precipitated severe self-injury were only reversible when plasma blood phenylalanine concentrations were titrated to near normal ranges and daily phenylalanine intake was strictly controlled. This case may offer a potential explanation for some of the late treatment failures that have been reported and suggest new avenues to explore in the late treatment of PKU.
Williams
K
K
Monson Developmental Center, Springfield, MA 01119, USA.
D000368:Aged; D001519:Behavior; D005684:Gait; D006801:Humans; D007866:Leg; D008297:Male; D010649:Phenylalanine / Q000008:administration & dosage* / Q000097:blood*; D010661:Phenylketonurias / Q000150:complications / Q000178:diet therapy* / Q000503:physiopathology; D016728:Self-Injurious Behavior / Q000178:diet therapy / Q000209:etiology; D013035:Spasm / Q000178:diet therapy / Q000209:etiology; D014202:Tremor / Q000178:diet therapy / Q000209:etiology
D010649:Phenylalanine