The National Alpha-1 Antitrypsin Deficiency Targeted Detection Programme

Title: The National Alpha-1 Antitrypsin Deficiency Targeted Detection Programme
Author(s): T. Carroll G. Kelly O. Cahalane I. Ferrarotti S. Ottaviani G. McElvaney
Institution: Royal College of Surgeons in Ireland
Poster: Click to view poster
Category: Asthma and COPD
Abstract: Alpha-1 antitrypsin deficiency (AATD) is a genetic disorder that can cause lung, liver, and skin disease. The most common harmful mutation is Z (Glu342Lys, rs28929474), carried by 1 in 25 Irish people (1). Guidelines advocate screening all COPD, poorly-controlled asthma, cryptogenic liver disease and panniculitis patients, as well as first degree relatives.

Over 21,000 individuals have been screened to date following ATS/ERS guidelines in a national targeted detection programme. AAT phenotyping is by isoelectric focusing and AAT quantification is by turbidimetry. Rare and novel mutations are identified by SERPINA1 gene sequencing.

We have identified 381 ZZ, 384 SZ, 112 SS, 3,750 MZ, and over 200 individuals with rare phenotypes (e.g. IZ, FZ, and IS). A number of rare and novel SERPINA1 mutations have also been identified, including 5 different Null (Q0) mutations.

Our results illustrate the high prevalence of AATD in Ireland and the efficacy of targeted detection. Advantages of a diagnosis include increased smoking cessation and family screening. Systematic testing for AATD can help alleviate the burden of COPD which remains the primary cause of winter hospital admissions. We strongly advocate that all COPD patients should be tested for AATD, regardless of age or smoking status, as per guidelines.

1. Carroll TP, O'Connor CA, Floyd O, McPartlin J, Kelleher DP, O'Brien G, et al. The prevalence of alpha-1 antitrypsin deficiency in Ireland. Respir Res. 2011;12(1):91.