Undefined differences in pathophysiology between cystic fibrosis (CF) and bronchiectasis mean clinicians have to continue to exercise caution in extrapolating evidence from one group to another.
Speaking at the TSANZSRS meeting on Why doesn’t treatment for CF bronchiectasis work in non-CF related bronchiectasis? Associate Professor Luke Hoffman said he thought the topic was however ‘deliberately provocative’.
He said that some treatments do work in both diseases, but that CF was obviously a much more homogenous disease than bronchiectasis.
“Bronchiectasis has been a basket term for all sorts of disease and therefore the response to treatment can be heterogeneous,” he said.
Studies have shown there is a lot of overlap in the microbial DNA, viscosity and purulence of sputum in patients with CF and bronchiectasis – suggesting mucoactive treatments should work across both groups of patients.
However a 2017 meta-analysis confirmed that while hypertonic saline might benefit patients, DNase didn’t, and may in fact be harmful.
This finding reinforced earlier TSANZ guidelines, which contraindicate recombinant human DNase in bronchiectasis and chronic suppurative lung disease.
He added that physiotherapy addressing mucociliary clearance did work in both patient groups.
Associate Professor Hoffman, from the University of Washington and Seattle Children’s Hospital, said the pathogens found in CF and bronchiectasis were often the same players such as Haemophilus, Strep pneumonia, M. catarrhalis, Staph aureus and P. aeruginosa, just with different prevalences.
He added that taxonomically, the microorganisms found in children with CF or bronchiectasis were quite similar but differed by about 50% in adults.
“Are we driving these differences?” he asked.
He said long-term oral antibiotics should not be used routinely in bronchiectasis but were used in children with CF.
“Extrapolating success from CF to bronchiectasis is tricky. Careful consideration of phenotype and endotypes is required,” he said.
He highlighted a recent Review article in Pediatric Pulmonology which addresses the management of bronchiectasis in children.