Chronic inhaled antibiotic therapy in people with cystic fibrosis with Pseudomonas aeruginosa infection in Germany

Background: Several clinical guidelines recommend chronic inhaled therapy for pwCF (people with cystic fibrosis) and chronic Pseudomonas aeruginosa infection of the lungs.Methods: To demonstrate what kind of therapy regimens are used in Germany, we retrospectively analysed chronic inhaled antibiotic therapy within the cohort of the German CF Registry in 2020. For comparison we also analysed the use of inhaled antibiotics in pwCF with intermittent Pseudomonas or without Pseudomonas infection. Results: A total of 1960 pwCF had chronic P. aeruginosa infection and were retrospectively evaluated. Almost 90% (n = 1751) received at least one inhaled antibiotic. The most commonly used inhaled antibiotic was colistin solution for inhalation (55.2%), followed by aztreonam solution for inhalation (32.6%) and tobramycin solution for Inhalation (30%). Almost 56% of adults and 44% of children alternated two antibiotics for inhalation. In children, alternating colistin + tobramycin was the most often used regimen. In adults, only 23% used colistin + tobramycin; there was a wide range of treatment regimens among adults using two inhaled antibiotics alter-nately. 2456 pwCF had no Pseudomonas infection, but almost 24% had a chronic inhaled antibiotic therapy, while 56% of 361 pwCF and intermittent chronic Pseudomonas infection had a chronic inhaled antibiotic therapy.Conclusion: In all three groups the most commonly used inhaled antibiotic was colistin solution for inhalation. Almost 56% of adults and 44% of children with chronic Pseudomonas infection alternated two antibiotics for inhalation. It will be interesting to see how the introduction of the highly effective modulator elexacaftor/ tezacaftor/ivacaftor will change the use of inhaled antibiotics.