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Updated: Jul 25, 2026
06:15
Protocol and Guidelines for Point-of-Care Lung Ultrasound in Diagnosing Neonatal Pulmonary Diseases Based on International Expert Consensus
Published on: March 6, 2019
Rare alpha-1-antitrypsin phenotypes and liver-test abnormalities during infancy
1Department of Paediatrics, Regional Hospital, Bozen, Italy. pediat@asbz.provincia.bz.it
Acta Paediatrica (Oslo, Norway : 1992)
|May 3, 2001
Summary
Neonatal screening identified rare alpha-1-antitrypsin (alpha1-AT) deficiency carriers. Early detection of PiFZ and PiPZ phenotypes allows for interventions to mitigate risks like pulmonary emphysema.
Area of Science:
- Medical Genetics
- Neonatal Screening
- Pulmonary Medicine
Background:
- Alpha-1-antitrypsin (alpha1-AT) deficiency is a genetic condition increasing risk for lung and liver diseases.
- Neonatal screening is crucial for early identification of genetic disorders.
- Phenotyping allows for the identification of specific alpha1-AT alleles.
Purpose of the Study:
- To evaluate the effectiveness of neonatal screening for alpha-1-antitrypsin (alpha1-AT) alleles.
- To identify infants with abnormal alpha1-AT phenotypes and assess associated risks.
- To determine the prevalence of rare alpha1-AT phenotypes in a Northern Italian population.
Main Methods:
- Analysis of 71,675 dried blood samples from neonatal screening over 14 years.
- Isoelectric focusing used to determine alpha1-AT alleles.
- Liver enzymes (alanine aminotransferase, gamma-glutamyltransferase) measured in infants with abnormal phenotypes.
Main Results:
- Identified 17 PiMV, 11 PiMF, 11 PiMP, 5 PiMN, 3 PiMR, 3 PiFZ, 2 PiPZ, and 1 PiMG phenotypes.
- Two infants (PiMV, PiFZ) showed elevated liver enzymes.
- PiFZ and PiPZ carriers had low alpha1-AT levels (0.78 and 0.85 g/L), indicating a risk for pulmonary emphysema.
Conclusions:
- Neonatal screening based on phenotyping is effective in early detection of rare alpha1-AT deficiency carriers.
- Early identification of at-risk individuals (e.g., PiFZ, PiPZ) enables preventative measures, such as discouraging smoking.
- This screening approach facilitates timely medical intervention for alpha1-AT deficiency.
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