immunoreactive trypsinogen
Pronunciation: /ˌɪmjʊnoʊriˈæktɪv ˌtrɪpˈsɪnoʊdʒən/
A pancreatic enzyme precursor measured as the primary screening marker for cystic fibrosis in newborns.
Full Definition
Immunoreactive trypsinogen (IRT) is an enzyme precursor produced by the pancreas and used as the primary biochemical marker for cystic fibrosis screening in newborn programs. In infants with cystic fibrosis, thick secretions block pancreatic ducts, leading to elevated IRT levels in blood. However, IRT can also be elevated due to other conditions such as prematurity, birth stress, or other pancreatic disorders, necessitating second-tier testing or DNA analysis for confirmation. IRT levels typically decrease with age, making timing of collection critical for accurate interpretation.
Usage
Usage note: Often abbreviated as IRT in laboratory contexts; spell out on first use in clinical documentation.
In Context
- "Immunoreactive trypsinogen levels were markedly elevated, prompting DNA analysis for cystic fibrosis mutations." — laboratory report
- "The immunoreactive trypsinogen assay demonstrates excellent analytical precision across the clinical range." — validation study