Molecular epidemiology of Pseudomonas aeruginosa from cystic fibrosis in Sicily: Genome macrorestriction analysis and rapid PCR-ribotyping

This study addresses the epidemiologic relatedness of a collection of Pseud omonas aeruginosa isolates from cystic fibrosis patients attending the Pedi atric Clinic, Catania, Sicily. Genome macrorestriction analysis after pulse d field gel electrophoresis (PFGE) was used to characterise all strains. Fu rthermore, a rapid typing procedure, developed in this study, based on poly merase chain reaction amplified ribosomal DNA spacer polymorphisms (PCR-rib otyping), straight from bacterial cultures, was used. On the basis of macro restriction analysis after PFGE, persistence of infection was shown in all patients; two cross-transmission episodes were identified in the nosocomial as well as in the familiar environment. PCR-ribotyping proved to be useful for a DNA-based identification test, suitable for screening purposes. The rapid amplification protocol here tested is proposed to evaluate the discri minatory power of other specific target sequences in PCR-based typing assay s, for epidemiologic purposes.