PCR ribotyping for characterizing Salmonella isolates of different serotypes

The 16S-23S intergenic spacer region in 218 strains of Salmonella isolated from four Italian hospitals during the period from 1977 to 1994 was analyzed by PCR ribotyping. This molecular typing technique allowed for the identification of seven different and specific electrophoretic profiles for the seven serovars S: enteritidis, S. london, S. anatum, S. panama, S. heidelberg, S. agona, and S. goldcoast. Otherwise, the spacer region appears to be polymorphic in S. typhimurium S. infantis, and S. derby since we could identify eight, six, and four different ribotypes, respectively.