Introduction and objectives BTS guidelines recommend to try and eradicate Pseudomonas aeruginosa when first isolated from patients with non-CF bronchiectasis. The aims of this study were to 1) define the different eradication regimens used in our respiratory centre and 2) evaluate their efficacy.

Methods The medical notes of adult non-CF bronchiectasis patients who underwent eradication trial for P. aeruginosa, between 2007 and 2014, were retrospectively reviewed. Eradication was considered successful if all (and at least 3) respiratory samples collected during the 6-month period following initiation of eradication were free of P. aeruginosa.

Results During the study period, 67 patients (58% male, average age 63.0 yrs) had at least one eradication trial. The majority of regimens used combined nebulised colomycin with either oral ciprofloxacin or intravenous antipseudomonal antibiotics as first line therapy, (Table 1, n = 57; 85%). Overall, first eradication attempts were successful in 52% of cases (35/67). Regimens including nebulised colomycin were more effective (n = 23/38; 60%) than those without it (20%; 2/10) (Fisher`s exact test, p = 0.04). Longer courses of ciprofloxacin (>3 weeks) did not improve outcome in comparison with shorter (≤3 weeks) courses (p = NS). Furthermore, intravenous antibiotics were not superior to oral ciprofloxacin (p = NS). Amongst the 32 patients who failed to eradicate P. aeruginosa in the first instance, 20 underwent a second attempt. In comparison with first trials, overall success rate of second trials decreased to 35% (n = 7/20). However, this difference did not reach statistical significance (Fisher`s exact test, p = 0.3). Nineteen patients, who initially successfully cleared P. aeruginosa, required a 2^nd eradication trial later during the study period. For those patients, the eradication success was 53%, comparable to the first one.

Conclusions Eradication regimens combining systemic and nebulised antibiotics appear more effective than systemic antibiotics alone to achieve P. aeruginosa eradication in non-CF bronchiectasis patients.