Molecular epidemiology of Pseudomonas aeruginosa from Italian cystic fibrosis patients

Abstract number: P1676

Morelli P., Melioli G., Mentasti M., Cirilli N., Manso E., Gioffrè F., Scuteri D., D'Aprile A., Manno G.

Background: The means of transmission of Pseudomonas aeruginosa (PA) in Cystic Fibrosis (CF) affected patients have not been clearly established. Many CF patients appear to acquire the organisms from the natural environment and not from other CF patients (Speert et al., 2002). Other indications, on the contrary, suggest that some clonal lineages are widespread among the CF population, apparently contracted through cross infection from other CF patients.

Aim: Address the type of transmission and/or environmental acquisition of PA and define if epidemic strains are circulating in Italy.

Methods: A collection of 340 strains from 183 pts attending 4 CF centres located in north (A), centre (B) and south Italy (C and D), and 55 environmental (11 from hospital sinks, 44 from swimming pool and mineral water) were genotyped by BOX-PCR (Rademarker J.L.W et al. 1998). A PA panel control strains included: PA01, ATCC 27853, European clone C (EC), Manchester Epidemic Strain (MES) and Liverpool Epidemic Strain (LES). The cluster analysis was performed by "Gel Compar II". MLST analysis of major clonal group was performed as described by Curran et al. 2004 (

Results: A total of 179 genotypes were found. 132 pts were colonised with a single PA genotype, and 46 with two o more genotypes. A total of 82 pts showed genotyped "shared" with other pts while 86 pts had "unique" genotype. 36 groups of pts carrying the same genotype (clusters) were observed: 22 of 2 pts size, 7 of 3 pts, 5 of 4 pts and 2 of 5 pts. For environmental strains 25 genotypes were found: 12 not shared, while 13 shared.13 clusters were found: 10 of 2 and 3of 3 sources. No Italian PA CF Strains showed genetically correlation with EC, LES and MES. No genetically correlation was observed between environmental and CF strains. No genotypes correlated were found among strains from Centres A, B and C. 3 genotypes found in 3 pts of centre B are highly correlated with 3 genotypes found in 2 pts of centre D. The profile (acs 39; aro 35; gua 71; mut 81; nuo 56; pps 36; trp 54), obtained by MLST, of this clonal group not showed relationship with European clones.

Conclusions: Environmental acquisition was not documented. The number of cluster found, suggest that person-to-person transmission may occurred, and the need of continuous survey, in the help of the infection control measures.

This study was supported by the Italian Cystic Fibrosis Foundation Grant FFC #8/2005

Session Details

Date: 19/04/2008
Time: 00:00-00:00
Session name: 18th European Congress of Clinical Microbiology and Infectious Diseases
Location: Barcelona, Spain
Presentation type:
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