How is Newborn Screening Ontario screening for cystic fibrosis?
NSO is using a two-step process to screen for cystic fibrosis. All samples will be tested daily for immunoreactive trypsinogen (IRT). Babies with an IRT below the 96th centile are screen negative for cystic fibrosis. Cystic fibrosis mutation analysis will be performed on all samples with an IRT above the 96th centile. Babies with an IRT above the 96th centile and 1 or 2 CF mutations are screen positive for CF. Babies with an IRT above the 99.9th centile and no CF mutations are screen positive for CF.
