For decades, lung disease has been the most visible and life-threatening part of cystic fibrosis. People might picture chronic (long-term) cough, breathlessness, recurrent chest infections and oxygen therapy.

But this only tells part of the story. Many people will be surprised to learn cystic fibrosis is also a gastrointestinal disease, affecting the gut and organs including the pancreas and liver.

Here’s how our understanding of cystic fibrosis has changed over the years and some common misunderstandings.

What exactly is cystic fibrosis?

Cystic fibrosis is the most common life-threatening genetic disease of its kind in white populations. About 3,800 Australians live with it.

It’s caused by mutations in the CFTR gene, which would normally produce a protein that acts like a microscopic “flush system” in major body organs. This protein usually helps move water and other contents across the surfaces of organs, keeping mucus and secretions thin and flowing normally.

But when genetic mutations lead to a faulty protein, mucus and secretions become thick and sticky. This leads to them stagnating rather than flowing, and obstructing organs and ducts. Mucus and secretions can become colonised by harmful microbes in the lungs and gut, leading to........

© The Conversation