A review of treatment regimens at first isolation of PA in a single cystic fibrosis center

<b>Introduction:</b> Chronic pulmonary infection with PA results in an increased rate of decline in lung function and higher mortality. There is no clear best practice for the treatment of first isolation of both pathogens. <b>Aims and Objectives:</b> We aimed to determine predictors of treatment failure, the efficacy of eradication regimens and long-term clinical outcome in our CF center. <b>Methods:</b> 309 patients were involved in the study. All sputum cultures collected between 2015-2019 were reviewed. Clinical findings, demographics and eradication regimens were compared retrospectively. <b>Results:</b> The mean age of patients at first PA isolation was 6,7 ± 5,73. Out of 120 PA positive cultures, 21,7% were eradicated. The most common preferred regimen was IV amikacin+ceftazidime due to hospital protocol. Highest success rate among treatment regimens were 14 days oral ciprofloxacin + 28 days inhaled tobramycin (5/8 pts, 62,5%) vs. amikacin-ceftazidime (16/79 pts, 20.3%)(p&gt;0.05). Sex, age, age at diagnosis, anthropometric measurements, microbial resistance of pathogen, FEV1, biliary-hepatic disease, dornase alfa or inhaled corticosteroid use, hospitalization and exacerbation rate and ΔF508 mutation were not statistically significant as a predictor. There was not any statistical difference between IV and oral treatment regimens. <b>Conclusions:</b> This retrospective review of PA eradication protocols revealed a lower success rate compared to other studies. Although oral ciprofloxacin + inhaled tobramycin regimen seems to be more effective, due to the limited number of patients it did not reach statistical significance. Randomized controlled studies are needed to determine an optimal treatment regimen.