Diagnosis and Presentation of Cystic Fibrosis

Abstract Most children with cystic fibrosis (CF) in current times are likely to be picked up through newborn screening programs and confirmed by the finding of two CF-causing mutations and a positive sweat test. They may be clinically well at the time of detection but likely to develop CF symptoms in time and will require prompt, effective intervention. Some children will be missed through the screening program, and pediatricians must remain vigilant to this possibility. No racial group is exempt from the disorder, and children of ethnic minorities or mixed heritage are at greatest risk of a delayed or a missed diagnosis. The clinical features of recurrent chest infections, malabsorption with pancreatic insufficiency in many but not all, salt losing syndromes, or an infant presenting with meconium ileus or rectal prolapse requires investigation. Recent consensus statements have provided useful guidance on the diagnostic criteria for CF. One of the unintended consequences of CF screening programs has been the detection of children in whom the full diagnostic criteria are not met. This group is referred to by the acronym CFSPID/CRMS. These children may require monitoring over time and possibly reevaluation depending on their clinical course. The range of clinical features for individuals with 2 CFTR mutations is wide and some may not develop symptoms at all or have an incomplete phenotype—often with single organ disease. Currently, such individuals often present clinically as adults and are not necessarily given the full cystic fibrosis label but considered to have a “CFTR related disorder.”