Improving outcomes in patients with cystic fibrosis

Cystic fibrosis (CF) is the most common fatal inherited disease in Caucasian people. Inheritance follows an autosomal recessive pattern. Recent data indicate that there are more than 9,000 patients with CF in the UK. At a cellular level there is an abnormal CF transmembrane conductance regulator (CFTR), a protein essential for chloride and sodium homoeostasis, caused by a mutation in the CF gene. The consequence of this abnormal protein is thick, viscous secretions in the lungs and GI tract, which lead to recurrent lung infections and pancreatic insufficiency with intestinal malabsorption. Most patients present in early childhood with classic CF. They show one or more of the typical CF phenotypic characteristics (chronic pulmonary disease, GI symptoms and malabsorption, nutritional abnormalities and sinus disease). A minority of patients have atypical CF. They tend to present at an older age, often in adulthood, are mainly pancreatic sufficient, have milder disease and a better prognosis. When CF is suspected the diagnosis can be confirmed by measuring sweat chloride concentration and by looking for CFTR mutations. Immunoreactive trypsinogen is measured in blood taken from a heel prick in all neonates, and is a marker of pancreatic injury consistent with (but not specific for) CF.