Key messages

• There is a lack of evidence to inform guidelines about antibiotic treatment for non-tuberculous mycobacteria in people with cystic fibrosis.

• Larger and more standardised studies looking at both laboratory results and symptoms are needed before we can make meaningful comparisons between different antibiotic treatments.

What is cystic fibrosis?

Cystic fibrosis is a genetic condition (when both parents pass the cystic fibrosis gene to their children) and people with cystic fibrosis have difficulty clearing sticky mucus from several organs in the body, which causes health problems. In the lungs, issues clearing mucus can result in infections. Over time, these infections lead to progressive lung disease (which gets worse over time due to scarring in the lungs), causing the lungs to work less well (a decline in lung function) and can even cause death. Successfully treating lung infections with antibiotics may slow the progression of lung disease and so extend life expectancy.

What are non-tuberculous mycobacteria?

Non-tuberculous mycobacteria are bacteria commonly found in the environment that cause lung infection in people with cystic fibrosis, resulting in worse symptoms. There are a few types of non-tuberculous mycobacteria. Antibiotics may destroy non-tuberculous mycobacteria and improve lung function, but antibiotics can have unpleasant effects (for example, feeling or being sick, diarrhoea, not feeling hungry) and treatment is often prolonged.

What did we want to find out?

Current antibiotic treatment guidelines for non-tuberculous mycobacteria lung disease are not based on evidence specific for people with cystic fibrosis. We wanted to find out which antibiotics are the most effective for them.

What did we do?

We looked for studies comparing antibiotic treatments to no antibiotic treatment or to different antibiotic treatments in people with cystic fibrosis of any age with non-tuberculous mycobacteria infection.

What did we find?

We found one small study from 2003 describing just 11 people with cystic fibrosis aged between 10 and 36 years and their treatment for non-tuberculous mycobacteria infection. All had had the infection for a long time. People received different antibiotics depending which type of non-tuberculous mycobacteria the person had.

The study reported that in 10 out of 11 people, the non-tuberculous mycobacteria infection had cleared up. Five people reported at least one unwanted event; three reported sensitivity to light when taking an antibiotic called ciprofloxacin, while each of the following events was reported once: impaired hearing, convulsions (fits), nerve problems (for example, pain, numbness and weakness) and lupus erythematous (a condition where the body attacks its own tissue). There was no consistent effect on lung function, with one measure increasing in six people, decreasing in four people and remaining the same in one person. When using another measure, lung function increased in eight people and decreased in three people. Two people died as a result of progression of cystic fibrosis two years after completion of treatment for non-tuberculous mycobacteria infection. Another person died of bleeding in the digestive tract and problems with her kidneys eight years after receiving a lung transplant (an operation that replaces the diseased lungs with healthy lungs from another person); her infection had cleared and remained clear until her death. Eight people gained weight, while three people lost weight. Investigators also reported body mass index in three people (which is an indicator of how much body fat there is). The values decreased slightly in two people and increased slightly in one person.

What are the limitations of the evidence?

Based on the quality of the study, its design and the available evidence, we are very uncertain about the effects of the different antibiotics on lung infections, lung function and unwanted effects.

How up to date is this evidence?

The date of the latest search is 14 October 2024.