Comparative analysis ofShigella sonneibiotype g isolated from paediatric populations in Egypt, 1999–2005

Abstract

SUMMARYStrain characteristics of 51Shigella sonneiisolates obtained from children seeking medical care (MC) and 48 isolates recovered during a prospective diarrhoea birth cohort (BC) study were compared. Biochemical characterization and antibiotic susceptibility testing determined that allS. sonneiisolates were biotype g and multidrug-resistant. Plasmid profiling identified 15 closely related patterns andXbaI pulsed-field gel electrophoresis confirmed the high degree of genetic similarity between isolates. AllS.sonneiisolates harbouredipaHand class II integrase genes and 84·3 and 80% of the MC and BC isolates, respectively carried thesengene. Neither the class I integrase nor thesetgene was detected. Our results indicate thatS. sonneiisolates associated with severe diarrhoea were indistinguishable from those associated with mild diarrhoea. Additional genetic tests with greater discrimination might offer an opportunity to determine genetic differences within the globally disseminating biotype g clone.