[Evaluation of the usefulness for neonatal mass screening in light of 35 years personal experience].

The results and the significance of neonatal mass-screening programmes for inborn errors of metabolism, conducted by the National Research Institute of Mother and Child (NRIMC), are discussed. As the first in Poland, in 1964, mass-screening for phenylketonuria (PKU) was introduced. The BIA-Guthrie test was used.

Hyperphenylalaninemia in Polish children's population.

Differential diagnosis in 144 cases of hyperphenylalaninemia detected through the newborn screening is discussed. In 123 infants phenylketonuria was diagnosed, so they were treated with the low phe diet. Verificatory examinations performed in diagnostically doubtful cases with the use of protein loading confirmed persistent enzymatic defect in all of them.