Cystic fibrosis: newborn screening in America.

Cystic fibrosis is the most common lethal genetic disease in Caucasians, manifesting as progressive lung dysfunction, pancreatic insufficiency, and intestinal disease. CF was traditionally diagnosed clinically, either because of a family history or occurrence of meconium ileus, or as a result of intestinal malabsorption and chronic pulmonary disease. In 1979, it was discovered that immunoreactive trypsinogen was increased in neonatal dried-blood specimens on Guthrie cards, making it possible to screen neonates. During the past decades, survival rates of patients with CF have improved significantly (see Figure 5). To continue this progress, universal newborn screening has been implemented in many states as an addition to the arsenal of therapies and strategies to improve survival. National newborn-screening programs to identify CF patients after birth have been adopted for a number of years in Europe, Australia, and Canada. As expected, many benefits have been seen due to the early identification of CF patients, including improved survival, better lung function and growth with less intensive therapy, and reduced cost of therapy. To date, 37 states in the United States have adopted similar programs, in the hopes of improving CF outcomes. This welcome trend should help improve the lives of CF patients living in America.