Cystic Fibrosis Patients Have More Bacteria—Good and Bad—In the Lungs

In 2008, the United States National Institutes of Health (NIH) launched a campaign to better understand the relationship between naturally occurring bacteria in the body and disease. The Human Microbiome Project, as it came to be called, laid the foundation for what we currently understand about the relationship between bacteria and human health. As technology and medicine have advanced, scientists are beginning to suspect that bacteria have a more critical role in human health than ever imagined.

The Human Microbiome Project confirmed that more than 10,000 unique microbial species exist within the human body. These are not bacteria that get into your system from the outside world. They grow and live throughout the human body, most abundantly in the gut and along the gastrointestinal tract. As we come to understand more about the role that these bacteria have to play in your body, scientists are working to include both the positive and negative impacts of bacteria in disease and treatment of disease.

Research directed at understanding interactions between bacteria and disease has recently made discoveries in the field of cystic fibrosis. It has been determined that cystic fibrosis patients have more bacteria overall in their lungs than those with other diseases. This above average number of bacteria includes both good and bad bacteria, and the results of the study have opened the door for future studies about the interactions between these bacteria and the nature of the cystic fibrosis.

The lung microbiome

Originally, healthy lungs were thought to be sterile, without bacteria or other agents in them. It was only recently that scientists discovered a vast microbiome living in the lower respiratory system, in cases of both health and disease. Studies on the lung microbiome have expanded significantly, and though the lungs were not originally included in primary studies performed by the Human Microbiome Project, subsequent studies have provided critical insight into the nature of respiratory disease.

Healthy lungs begin as sterile organs before birth, and acquire a microbiome sometime after birth, with a majority of the baby’s microbiome coming from its mother. At some point, the bacteria in the baby’s lungs begin to differentiate, and we say that some of these bacteria are good, and others are bad for a person’s individual health. In reality, they exist side-by-side in equilibrium, and it is only when these bacteria are thrown out of balance that people begin to experience symptoms or develop chronic illnesses.

Individuals with cystic fibrosis produce an excess of mucus that builds up over time in the lungs and pancreas. Their bodies also fail to properly transport sodium ions, which sometimes shows up as a symptom in salty-tasting skin. This is significant, because the lungs require sodium to transport sugar molecules into the lung’s cells. Without the ability to do so, the sugar remains on the surface of the lungs, giving bacteria the opportunity to grow and multiply far beyond the natural rate.

As researchers examine the lung microbiome in cystic fibrosis patients, interesting findings suggest that the bacteria may be both part of the problem, and part of the solution. Already, in other fields that are studying microbiomes, scientists are beginning to attempt to reconfigure microbiomes in individuals with chronic illnesses. The hope is that in reconfiguring the bacteria associated with disease, the healthy microbiome will alter the progression of disease, and possibly even reverse symptoms.

Read on to learn more about these new findings.