Treating MRSA in cystic fibrosis patients

Cystic fibrosis (CF) is a very rare genetic disorder, affecting over 70,000 people worldwide. CF is present from birth and usually identified by age two, due to the excessive amounts of mucus that clog the lungs and digestive tract. Current medical treatments involve managing symptoms, such as inhalers to open the airways, steroids to reduce inflammation, and mucus thinners to help control excess secretions. Unfortunately, there is no known cure at this time.

A common concern in patients with cystic fibrosis is Methicillin-resistant Staphylococcus aureus (MRSA) that can cause lung infections in these already vulnerable patients.Therefore, it is important to learn more about the impact this deadly bacterium has on the fragile lungs of patients with cystic fibrosis and how doctors can best treat infections without causing antibiotic resistance in the process.

Gene Mutation in Cystic Fibrosis

Gene mutations in cystic fibrosis present as errors in cystic fibrosis transmembrane conductance regulator (CFTR) gene development, causing a CFTR protein malformation, erroneous protein folding, or in some cases, the absence of CFTR altogether. The CFTR protein, if working properly, facilitates the passage of chloride through the cell walls of major organ cells to achieve fluid balance.

When this protein is not present or not functioning correctly, chloride is unable to pass through the cell wall and builds up in the cell. The resulting fluid imbalance causes mucus to become very thick and sticky. The built-up mucus leads to lung infections, poor digestion, and problems in the reproductive system. Eventually, respiratory failure can occur, particularly if the patient is exposed to MRSA.

Pig Lungs Used in Research Study

To help combat the devastating effects of MRSA on CF patients, scientists at the University of Warwick have developed a new technique using pig lungs as models. In these studies, researchers mimicked human CF conditions by placing artificial mucus affected by staphylococcus aureus (S. aureus) into pig lungs. The research helped discover that S. aureus bacteria colonized the mucus rather than forming abscesses in the organ’s tissueslf, as previously thought.

While researchers still do not fully understand the process, it has been shown that bacteria attach to the mucus plugs in the tiny airways of the lungs. This can lead to frequent infections not fully treatable by a regular course of antibiotics. In the case of MRSA, antibiotic resistance in CF patients is common.

Further Research Leads to Better Treatment of Cystic Fibrosis and MRSA

As a result, researchers suspect that antibiotics are not the best course of treatment for lung infections in cystic fibrosis patients. Further research on how lungs are affected by S. aureus bacteria will better equip medical professionals to develop treatments that are more effective and do not risk antibiotic resistance. In the future, researchers hope to develop a better understanding of how CF affects the lung, and how to stop this deadly infection from harming patients.


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