Rare alpha-1-antitrypsin phenotypes and liver-test abnormalities during infancy

Over 14 y of neonatal screening 71,675 dried blood samples were examined for the alpha-1-antitrypsin (alpha1-AT) alleles by isoelectric focusing in the Province of Bozen, Northern Italy. In infants carrying abnormal phenotypes the liver enzymes alanine aminotransferase and gamma-glutamyltransferase were determined at 2, 5 and 12 mo of age. In 17 neonates the PiMV phenotype was found, in 11 PiMF, in 11 PiMP, in 5 PiMN, in 3 PiMR, in 3 PiFZ, in 2 PiPZ and in 1 the PiMG phenotype was found. Two infants,1 carrying the PiMV and 1 the PiFZ phenotype showed at the age of 2 and 5 mo, respectively, elevated values of the liver enzyme S-ALAT[CE1]. Only the PiFZ and PiPZ carriers displayed low enough levels of alpha1-AT of 0.78 and 0.85 g l(-1) respectively, to be at moderately increased risk of pulmonary emphysema. Their early detection through the screening should discourage them from dangerous smoking habits.Only a neonatal screening based on phenotyping can detect these rare carriers early in life.