Clonal typing of P.aeruginosa strains in non-CF bronchiectasis

Introduction P.aeruginosa is the most clinically significant infecting organism in non-CF bronchiectasis. Aims and Objectives To determine the whether there are clonal strains within the non-CF bronchiectasis population in Northern Ireland. Methods In total 50 P.aeruginosa isolates from 26 patients were analyzed by pulse field gel electrophoresis (PFGE). Results There were 10 individual strains identified by PFGE band pattern after DNA macrorestriction. 5/50 isolates were unique novel strains from 5 separate individuals. There were two dominant strains in this cohort. BELFCITPA-1 in 14/50 isolates in 5 patients. 12/50 isolates in 7 patients were identified as BELFCITPA-5. Stable patients were found to have one strain per sample whereas there was greater diversity within the samples collected from patients with an exacerbation, 1.25 strains on average. ConclusionThere are a number of common strains of P.aeruginosa found in the sputum of non-CF bronchiectasis patients. Although there are at least 2 clonal strains identified in this small cohort, it is unclear whether this is because they are common environmental strains in the region or because of cross-infection between individuals.