An exciting new discovery to reduce chronic infection in cystic fibrosis patients

In Summary

Chronic microbial infections are a major problem for patients   with cystic fibrosis. In particular, when an opportunistic ‘superbug’ called Pseudomonas aeruginosa forms a chronic infection in their lungs, it can cause serious damage to lung tissue and function.

New research funded by the HRB and the Irish Thoracic Society has found that bile acids aspirated from the digestive system into the lungs trigger Pseudomonas aeruginosa to form hard-to-shift infections. This discovery opens up new intervention treatment options to protect patients with CF by stopping bile from getting into the lungs, and thereby reduce chronic infections.

The Problem

People with the inherited condition cystic fibrosis (CF) are prone to chronic lung infections, particularly from the bacterium Pseudomonas aeruginosa. This can damage their lungs and often means extended stays in hospital. Antibiotic medicines do not work well against these chronic forms of infection.

The Project

A team in Cork and Australia led by Professor Fergal O’Gara examined the potential role of bile acids in driving chronic lung infection in CF. Bile is normally present in the gallbladder and digestive system, but if patients have acid reflux or ‘heartburn’ then bile can move up towards the mouth and be aspirated into the lungs. The majority of patients with CF can experience reflux and bile acids entering the lungs.

The Outcomes

We now know that: –

Bile acids can prompt Pseudomonas aeruginosa bacteria to transition from acute to chronic infection that do not respond to antibiotic therapy.
 
This discovery has led to new clinical trials to determine if reducing the movement of bile into the lungs decreases chronic infections in CF patients.

The finding may also inform new physiotherapy approaches for patients with CF, to minimise the movement of bile into the lungs.

Professor Fergal O’Gara, Professor of Microbiology, BIOMERIT Research Centre, University College Cork, says :

‘Based on this research, we are the first in the world to demonstrate that the entry of bile acid into the lungs triggers bacterial infections to move from the acute into the chronic state. We are confident that this could lead to new approaches to help minimise the onset of chronic infections and damage to the lungs in patients with cystic fibrosis’.