Source: The Conversation (Au and NZ)
Olena Malik/Getty 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 inflammation. In Australia and countries with established newborn screening programs, most cases are now detected through newborn screening (via the heel-prick blood test).
However, milder forms of cystic fibrosis or people who carry rare mutations can sometimes be diagnosed later in life. But there is likely under-recognition and under-diagnosis of cystic fibrosis. The idea it only affects white people is essentially a myth.
It is entirely plausible the Indian subcontinent has the greatest number of people with undiagnosed cystic fibrosis. We just haven’t looked. Now let’s take a look at three other common misconceptions about cystic fibrosis in detail.
Myth 1: cystic fibrosis is mainly a lung disease The earliest signs of cystic fibrosis begin in the gastrointestinal tract – even before birth. It can be first detected during routine antenatal scans showing bowel changes, or at birth with symptoms of bowel obstruction.
Historically, many young children with cystic fibrosis died from complications affecting the pancreas and intestines before severe lung disease had time to develop. But as survival has improved, gastrointestinal complications are increasingly recognised as a major ongoing health challenge.
These include bowel obstruction, severe constipation, stomach pains, gastroesophageal reflux or nausea. These symptoms affect all people with cystic fibrosis whatever their age, and significantly affect people’s quality of life. As people tend to survive longer with cystic fibrosis than in the past, adults now face the risk of gastrointestinal cancers including colorectal (bowel) cancers.
These are diagnosed at higher rates and at a younger age than the general population. We’ve known about these cancer risks for decades. But historically they received less attention because many people did not survive long enough for cancers to emerge as a major issue.
That is now changing rapidly. Some health professionals also still consider cystic fibrosis mainly a lung disease. This sometimes means gastrointestinal symptoms are under-recognised or under-prioritised despite their major impact on daily life. Myth 2: cystic fibrosis is a death sentence Not long ago, most children born with cystic fibrosis did not survive into adulthood.
Today, outcomes are dramatically different with more adults than children (60% vs. 40%) living with cystic fibrosis, and with a predicted survival age of 64 years for those born in 2019–2023. Introduction of newborn screening, along with earlier support and treatment for nutritional and lung issues, have all contributed to longer life expectancy.
However, the biggest and most recent transformation has come from a class of medicines called CFTR modulators. These medications can substantially restore the function of the faulty CFTR protein. Myth 3: we now have a cure However, current medicines, including CFTR modulators, do not fully reverse organ damage.
Not everyone is eligible for them, and responses vary between individuals. While most people see major improvements in lung function, the impact of CFTR modulators on the gastrointestinal system has been less pronounced to date.
If these medicines are started in early childhood, they can restore partial function to the pancreas. But gastrointestinal symptoms and advanced liver disease can persist, and the risk of gastrointestinal cancers remains. Researchers are now trying to better understand the gut side of cystic fibrosis, including the role of diet, gut inflammation and the gut microbiome (the body’s dynamic community of microorganisms).
For now, the story of cystic fibrosis is no longer simply about surviving lung disease. It is increasingly about understanding how a genetic condition affects the entire body – and ensuring people living longer with cystic fibrosis can also live well.
(Keith) Chee Y.
Ooi has performed roles as a speaker and on advisory boards for Vertex Pharmaceuticals. He receives funding from the National Health and Medical Research Council (NHMRC), United States Cystic Fibrosis Foundation and Gastroenterology Society of Australia (GESA).
He received funding from National Institutes of Health (NIH) and Australian CF Research Trust.
Original source: https://analysis1.mil-osi.com/2026/07/01/cystic-fibrosis-doesnt-just-affect-the-lungs-its-a-gut-disease-too/