Speech and language skills in children with early treated phenylketonuria.

The speech and language skills of 29 children with early treated phenylketonuria (PKU) were reported. The performances of two experimental groups that differed in language development level on standardized speech/language tests were compared with the performances of appropriate control groups matched for age, sex, and socioeconomic level. No significant differences were found on speech and/or language measures between either of the two experimental groups and their respective controls. Examination of individual scores, however, did reveal linguistic impairment in a small number of persons with PKU. No pattern of linguistic deficit was found nor were there any consistent relations between individual speech/language scores, cognitive abilities, or dietary control ratings.