Early diagnosis of cystic fibrosis in the newborn period and risk of Pseudomonas aeruginosa acquisition in the first 10 years of life: A registry-based longitudinal study.

OBJECTIVE

Controlled clinical trial data have suggested that identifying asymptomatic cystic fibrosis (CF) patients through newborn screening improves health outcomes of affected children in the first decade of life. However, it is unclear whether these improvements also include a reduction in risk for bronchial infection, the major determinant of CF morbidity. The authors therefore investigated the association between early CF diagnosis and acquisition of Pseudomonas aeruginosa, the major bronchial pathogen, in the first decade of life.

METHODOLOGY

Longitudinal data on 3625 CF patients diagnosed between 1982 and 1990 and before 36 months of age were ascertained from the National Cystic Fibrosis Patient Registry. We compared P aeruginosa acquisition in the first 10 years of life among 4 groups: EAD (early asymptomatic diagnosis)-<6 weeks, by pre/neonatal screening, genotype, family history (n = 157); ESD (early symptomatic diagnosis) (n = 227); LAD (late asymptomatic diagnosis)-6 weeks to 36 months (n = 161); and LSD (late symptomatic diagnosis) (n = 3080). P aeruginosa acquisition was determined from yearly sputum and/or bronchoscopy cultures. Children whose CF diagnoses followed meconium ileus or whose cultures were obtained only from nasal samples were excluded from the study.

RESULTS

Kaplan Meier analyses for P aeruginosa acquisition were conducted for each diagnostic group. Regression models were used to generate adjusted relative hazards with EAD as the referent group. Relative hazards were 0.9 (95% confidence interval [CI]: 0.7-1.2) for ESD, 0.8 (95% CI: 0.6-1.2) for LAD, and 1.0 (95% CI: 0.7-1.2) for LSD. The risk of acquiring P aeruginosa was therefore not significantly different between children diagnosed early, late, asymptomatically, or symptomatically.

CONCLUSIONS

These data suggest that, despite improvements in other health outcomes from newborn screening for CF, early asymptomatic diagnosis of CF does not affect P aeruginosa acquisition.