Frequently asked questions

Frequently asked questions about cystic fibrosis

    Cystic fibrosis (CF) is a disease you are born with. It is a genetic disease meaning you inherit it from your parents.1

    CF is the result of two disease-causing CFTR gene mutations that produce defective CFTR protein channels. These channels are either too few in number or do not work correctly. When they do not work correctly, the channels do not stay open long enough or do not open as often as they should.1,2

    The normal CFTR gene (Cystic Fibrosis Transmembrane conductance Regulator) makes normal CFTR proteins. These proteins act like channels or ‘gates’ which open and close to allow water and chloride ions to move into and out of cells,3 for example in the lungs and pancreas.2

    Most people with CF are diagnosed as babies. Some countries (such as Austria, Switzerland and the UK) screen all newborns for CF, but this varies from country to country. CF is usually confirmed through a sweat test and a genetic test.5,6

    CF is a genetic disease meaning you inherit it from your parents. It is most common in Caucasian populations.7

    Approximately 35,000 people in Europe are affected by CF.8

    People with CF may experience a wide variety of symptoms including:

    • Wheezing, shortness of breath and persistent coughing.
    • Lung infections and lung disease.
    • Difficulty digesting food.
    • Poor growth, delayed puberty and slow weight gain.
    • Salty sweat.9

    We know of over 2,000 different CFTR gene mutations but only 242 of these cause CF and most are extremely rare.10

    You can either have two copies of the same CFTR gene mutation, or two different CFTR gene mutations.11

    Your CF genotype is the combination of CFTR gene mutations you inherited from your parents. If your CFTR mutations aren’t noted in your medical records it’s important to find out which mutations you have. This can be done using a genetic test provided by your doctor.11

    Everyone with CF is different. For many people with CF, treatment routines may be complex and time-consuming, and it may be important to establish a daily routine, be organised and plan for any changes to your daily routine.

    Fat is essential and an important part of a healthy diet.

    The exact amount of energy and fat needed varies from person to person so you should always consult your doctor or nurse for specific CF dietary advice.12

    Regular physical activity should be a central part of CF management for everyone living with the disease, regardless of age and severity.13When considering a new activity discuss it with your doctor or nurse first to make sure it is safe and appropriate for you.

    Remember to take special care when the weather is hot and humid.

      1. Orenstein DM. Cystic Fibrosis: A Guide for Patient and Family. 3rd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2004.

      2. Derichs N. Targeting a genetic defect: cystic fibrosis transmembrane conductance regulator modulators in cystic fibrosis. European Respiratory Review 2013; 22(127): 58 - 65.

      3. Wang W, Linsdell P. Conformational change opening the CFTR chloride channel pore coupled to ATP-dependent gating. Biochimica et Biophysica Acta (BBA) - Biomembranes 2012; 1818(3): 851 ̶ 860.

      4. Macdonald KD, et al. Cystic Fibrosis Transmembrane Regulator Protein Mutations. Pediatr Drugs 2007; 9(1): 1 ̶ 10.

      5. NHS Choices. Cystic Fibrosis - Diagnosis. Available from: Updated May 2014. Accessed June 2016.

      6. Cystic Fibrosis Foundation. About Cystic Fibrosis. Available from: Accessed September 2021.

      7. World Health Organization. The molecular genetic epidemiology of cystic fibrosis: report of a joint meeting of WHO/ECFTN/ICF(M)A/ECFS; June 19, 2002; Genoa, Italy. World Health Organization; 2004. Available from: Accessed June 2016.

      8. Farrell P. The prevalence of cystic fibrosis in the European Union. Journal of Cystic Fibrosis 7 2008: 450 ̶ 453.

      9. O'Sullivan B and Freedman S. Cystic fibrosis. Lancet 2009; 373(9678): 1891 ̶ 1904.

      10. US CF Foundation, Johns Hopkins University, The Hospital for Sick Children. The Clinical and Functional Translation of CFTR (CFTR2). Resources. Available at: Accessed February 2022.

      11. Welsh MJ, Ramsey BW, Accurso F, Cutting GR. Cystic fibrosis: membrane transport disorders. In: Valle D, Beaudet A, Vogelstein B, et al. eds. The Online Metabolic & Molecular Bases of Inherited Disease. The McGraw-Hill Companies Inc; 2004: part 21, chap 201.

      12. Borowitz D, et al. Consensus Report on Nutrition for Paediatric Patients With Cystic Fibrosis. J Pediatr Gastroenterol Nutr 2002; 35(3): 246 ̶ 59.

      13. Smyth A, et al. European Cystic Fibrosis Society Standards of Care: Best Practice guidelines. J Cyst Fibros 2014; 13: S23 ̶ S42.