Clinical outcomes associated with Achromobacter species infection in people with cystic fibrosis

Background: Achromobacter species are emerging pathogens isolated from respiratory samples of Patients with cystic fibrosis (pwCF) causing growing concerns in the CF community . The epidemiology and the clinical impact of Achromobacter in CF is unclear since data are restricted to small case control studies or selected populations . Aim: To characterize the effect of Achromobacter respiratory infection on CF lung disease. Methods: European CF Society Patient Registry data was analysed for association between Achromobacter infection and demographic/clinical characteristics and outcomes of pwCF. Results: Of eligible 38,795 patients, Achromobacter infection was reported in 2,093 (prevalence (95% CI) of 5.40% (5.17 - 5.62). The prevalence varied significantly between the countries and increased with age peaking at the age 20–30. Achromobacter infection was more prevalent in pwCF carrying class minimal function mutations, having worse nutrition or lower pulmonary function, and more patients inhaled an- tibiotics against P. aeruginosa . Patient infected with Achromobacter had similar pulmonary function and BMI to patients infected with P. aeruginosa at all age groups. Being infected with both bacteria was asso- ciated with significantly lower pulmonary function and BMI at all age groups. Conclusions: Achromobacter infection was associated with disease severity similar to infection with P. aeruginosa. Being infected with both bacteria is associated with even more severe disease. This suggests to study if eradication will improve the outcome of pwCF.