Alpha 1AT Levels Research Articles

Alpha-1-antitrypsin in umbilical cord serum: Pi phenotypes and relationships with idiopathic respiratory distress syndrome

The concentrations and phenotypes of serum alpha-1-antitrypsin (alpha1AT) were determined in 650 newborn infants. The distribution of these 650 subjects among the various Pi phenotypes confirms the higher frequency reported for the PiS allele in Latin populations. Serum alpha1AT levels vary between one phenotype and the other. Besides, at birth, infants weighing more than 2,500 g have alpha1AT levels significantly higher (P less than 0.001) than infants weighing less than 2,500 g; this difference in serum alpha1AT concentrations is due to the low alpha1AT levels found in preterm infants. The significantly lower alpha1AT concentrations found in preterms is associated with a higher risk of developing IRDS and with a mean birth weight under 2,000 g. Infants who develop IRDS frequently have lower alpha1AT levels than those who do not develop the syndrome, independently from body weight. On the basis of serum alpha1AT quantitation, newborn infants may be separated into two groups, characterized respectively by concentrations above or below 150 mg%. From our data, it appears that if the group with an alpha1AT concentration lower than 150 mg% is phenotyped, it is possible to differentiate infants with a high risk of fatal IRDS from individuals with a "pathological" phenotype.

Levels of alpha1-antitrypsin in the spring and autumn seasons.

In a group of 84 pairs of 11-year-old children of both sexes, the level of the alpha1-antitrypsin (alpha1-AT) were ascertained in the autumn and spring. Although the mean levels of alpha1-AT in the two seasons hardly differed, the highly significant seasonal changes in the distribution curves of alpha1-AT values were noted in boys, whereas the levels showed higher stability in girls.