Lessons learned from 20 years of newborn screening for cystic fibrosis

Med J Aust. 2012 Jan 16;196(1):67-70. doi: 10.5694/mja11.10686.


Objective: To compare three cystic fibrosis (CF) newborn screening strategies used in Victoria since 1989.

Design, setting and participants: Retrospective review of newborn screening and clinical records for people with CF born in Victoria between 1989 and 2008 to compare screening strategies: repeat immunoreactive trypsinogen (IRT) testing (IRT/IRT, 1989-1990), IRT and p.F508del mutation analysis (IRT/p.F508del, 1991-2006) and IRT with analysis of 12 CFTR mutations (IRT/12 mutations, 2007-2008).

Main outcome measures: Total number of infants screened, people identified with CF (by screening or clinical diagnosis), number of CF-affected terminations of pregnancy, and number of carriers detected.

Results: There were 420 people born with CF (live-birth prevalence, 1/3139; 95% CI, 1/2853-1/3462) and 78 CF-affected pregnancy terminations (overall prevalence, 1/2647; 95% CI, 1/2425-1/2896). Of the babies born with CF, 283 (67.4%) were detected by newborn screening alone, 61 (14.5%) had meconium ileus, 33 (7.9%) had a family history of CF, nine (2.1%) were diagnosed antenatally, and 34 (8.1%) were missed by screening (17 missed because IRT level was < 99th percentile, two with repeat IRT level not elevated, 14 without a screened CFTR mutation, and one with missing data). The sensitivities of the protocols were 86.6% for IRT/IRT, 89.9% for IRT/p.F508del, and 95.8% for IRT/12 mutations. Including 12 mutations in the analysis detected one patient who would otherwise have been missed and, had this protocol been implemented from 1989, it would have detected four others.

Conclusion: Most babies with CF without meconium ileus, a family history or antenatal diagnosis are detected by newborn screening. Despite improved sensitivity with the 12-mutation analysis, most infants detected would have been diagnosed using the IRT/p.F508del protocol.

Publication types

  • Comparative Study

MeSH terms

  • Cystic Fibrosis / diagnosis
  • Cystic Fibrosis / epidemiology*
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics
  • DNA / analysis
  • DNA / genetics
  • DNA Mutational Analysis
  • Female
  • Follow-Up Studies
  • Genetic Testing / methods*
  • Humans
  • Infant, Newborn
  • Male
  • Mutation
  • Neonatal Screening / methods*
  • Pregnancy
  • Prevalence
  • Prognosis
  • Retrospective Studies
  • Sweat / chemistry
  • Time Factors
  • Trypsinogen / genetics
  • Victoria / epidemiology


  • Cystic Fibrosis Transmembrane Conductance Regulator
  • Trypsinogen
  • DNA