Cystic fibrosis (Q40135)

Cystic fibrosis (CF) is a genetic disorder characterised by the production of sweat with a high salt content and mucus secretions with an abnormal viscosity. The disease is chronic and generally progressive, with onset usually occurring during early childhood or, occasionally, at birth (meconium ileus). Virtually any internal organ may be involved but the principle manifestations concern the breathing apparatus (chronic bronchitis), pancreas (pancreatic insufficiency, adolescent diabetes and occasionally pancreatitis) and, more rarely, the intestine (stercoral obstruction) or liver (cirrhosis). The usual presenting symptoms and signs include persistent pulmonary infection, pancreatic insufficiency, and elevated sweat chloride levels. However, many patients demonstrate mild or atypical symptoms, and clinicians should remain alert to the possibility of CF even when only a few of the usual features are present. Both criteria; clinical symptoms consistent with CF in at least one organ system and evidence of cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction must be met to diagnose cystic fibrosis.