title: Intellectual deficits after transient tyrosinemia in the term neonate.
abstract: In order to determine if prolonged, significant transient neonatal tyrosinemia (TNT) is injurious to the developing central nervous system, 15 term infants who had suffered from this disorder for a mean duration of 50 days underwent comprehensive psychometric evaluations at a mean (+/- 1 SD) age of 56.5 +/- 7.8 months. Their mean maximum detected tyrosine level had been 25.8 mg/dl (range, 13.6 to 42.0) and their defect was considered secondary to a combination of a high protein formula intake and a lack of supplemental vitamin C. Compared to a control group, significantly lower mean scores were obtained by the TNT group on the McCarthy Scale of Children's Abilities (77.1 vs. 92, P = .008) and the Illinois Test of Psycholinguistic Ability (92.3 vs. 109.9, P = .002). Performance scores varied inversely with the duration of TNT. Although these children are not classifiable as "mentally retarded," TNT may cause specific learning disabilities. There is, therefore, a need to determine the frequency of TNT in infants fed evaporated milk and other high-protein milk formulas and to develop ways to prevent its occurrence.
mesh_terms: D002675:Child, Preschool; D005191:Family Characteristics; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000097:blood / Q000150:complications*; D008607:Intellectual Disability / Q000209:etiology*; D008297:Male; D011581:Psychological Tests; D013997:Time Factors; D014443:Tyrosine / Q000097:blood*
chemical_list: D014443:Tyrosine