Removing Antibodies from Bloodstream May Reduce Chronic Lung Infections in Bronchiectasis

Removing Antibodies from Bloodstream May Reduce Chronic Lung Infections in Bronchiectasis

Removing particular antibodies from the bloodstream of patients with bronchiectasis may reduce the negative effects of chronic bacterial infections, the need for days spent in the hospital, and the use of antibiotics, new research shows.

The findings came from a study conducted at the University of Birmingham and Newcastle University, U.K., and may provide a new treatment strategy for antibiotic-resistant bacteria and for infectious diseases, with benefits for both patients and healthcare providers.

The study, titled “The Use of Plasmapheresis in Patients with Bronchiectasis with Pseudomonas aeruginosa Infection and Inhibitory Antibodies,” was published in the American Journal of Respiratory and Critical Care Medicine.

Bronchiectasis is a long-term condition that affects the airways, which become scarred and inflamed with thick mucus. The airways are widened and cannot clear themselves properly, meaning that the mucus builds up in them, offering an environment prone to infections by pathogens.

Patients suffering from bronchiectasis usually develop lung infections caused by Pseudomonas aeruginosa, a common and multidrug-resistant bacteria.

Now, researchers examined the effectiveness of a new treatment strategy in two patients with bronchiectasis affected with chronic P. aeruginosa infections resistant to many antibiotics. One patient was a 64-year-old male diagnosed with bronchiectasis at age 15, and the other one a 69-year-old female who had bronchiectasis from childhood.

“These patients had an excess of a particular antibody in the bloodstream. In contrast to the protective effect normally associated with antibody, in these patients the antibody stopped the immune system killing the Pseudomonas aeruginosa bacterium and this worsened the patients’ lung disease,” Prof. Ian Henderson, director of the Institute of Microbiology and Infection at the University of Birmingham and the study’s co-author, said in a news release.

“Perhaps counter-intuitively, we decided to remove this antibody from the bloodstream, and the outcomes were wholly positive,” Henderson said.

“We needed a brand new way of tackling this problem,” said Anthony De Soyza, senior lecturer at Newcastle University and the study’s lead author. “Working with kidney and immunology experts, we used a process known as plasmapheresis that is somewhat like kidney dialysis. The plasmapheresis involved the removal, treatment, and return of blood plasma from circulation, and was done five times in a week in order to remove antibody from the patients.

“We then replaced antibodies with those from blood donations. This treatment restored the ability for the patients’ blood to kill their infecting Pseudomonas,” De Soyza added.

When the patients had the specific antibody removed from their bloodstream through the technique plasmapheresis, they both experienced a rapid improvement in disease symptoms and well-being, as well as a greater independence and improved mobility.

“This shows that we can improve patient well-being significantly, by reducing the need for treatment and the numbers of days spent in hospital, which will also help to reduce the reliance on antibiotics,” Henderson said. “The next step is to do longer-term studies to investigate whether an earlier intervention, with slightly less aggressive therapies, could help prevent disease progression in patients.”

This is the first study using plasmapheresis to improve infection-related symptomatology in these patients. The researchers believe that further multicenter studies of the prevalence of inhibitory antibodies in bronchiectasis and other diseases with an infectious component will help them understand if the technique could be applied more widely.