title: Identification of a group of shigella-like isolates as Shigella boydii 20.
abstract: Infections by Shigella species are an important cause of diarrhoeal disease worldwide. Of 4198 Shigella isolates received by the French National Reference Centre for Escherichia coli and Shigella, 180 from patients with diarrhoea and dysentery in 2000-2004 did not react with any available polyclonal rabbit antisera used to identify the established Shigella serogroups. This study describes the molecular and phenotypic characteristics of these isolates in seroagglutination tests, molecular serotyping (rfb-RFLP and fliC-RFLP), ribotyping, detection of invasivity and enterotoxins genes, and antibiotic sensitivity. All isolates gave biochemical reactions typical of Shigella boydii, were mannitol-positive and indole-negative. They all carried invasion-associated genes, enterotoxin 2 [ShET-2] and an IS630 sequence. They had a unique ribotype that was distinct from all other Shigella and E. coli patterns. Further characterization by rfb-RFLP clearly distinguished this serogroup from all other Shigella or E. coli O-groups. The fliC-RFLP pattern corresponded to P4, an F-pattern which is associated with 10 different serogroups of S. boydii. A new antiserum prepared against strain 00-977 agglutinated all 180 isolates and cross-agglutination and absorption studies with anti-00-977 serum and anti-CDC 99-4528 (reference for the newly described S. boydii serogroup 20) serum showed identical antigenic structure. Furthermore, strains 00-977 and CDC 99-4528 had the same molecular serotype, ribotype and virulence genes.
authors.affiliation: French National Reference Centre for Escherichia coli and Shigella, Unité de Biodiversité des Bactéries Pathogènes Emergentes, Institut Pasteur, Paris, France.
authors.forename: Francine
authors.initials: F
authors.lastname: Grimont
authors.affiliation: French National Reference Centre for Escherichia coli and Shigella, Unité de Biodiversité des Bactéries Pathogènes Emergentes, Institut Pasteur, Paris, France.
authors.forename: Monique
authors.initials: M
authors.lastname: Lejay-Collin
authors.affiliation: International Centre for Diarrhoeal Diseases Research, Dhaka-100, Bangladesh.
authors.forename: Kaisar A
authors.initials: KA
authors.lastname: Talukder
authors.affiliation: French National Reference Centre for Escherichia coli and Shigella, Unité de Biodiversité des Bactéries Pathogènes Emergentes, Institut Pasteur, Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Carle
authors.affiliation: French National Reference Centre for Escherichia coli and Shigella, Unité de Biodiversité des Bactéries Pathogènes Emergentes, Institut Pasteur, Paris, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Issenhuth
authors.affiliation: French National Reference Centre for Escherichia coli and Shigella, Unité de Biodiversité des Bactéries Pathogènes Emergentes, Institut Pasteur, Paris, France.
authors.forename: Karine
authors.initials: K
authors.lastname: Le Roux
authors.affiliation: French National Reference Centre for Escherichia coli and Shigella, Unité de Biodiversité des Bactéries Pathogènes Emergentes, Institut Pasteur, Paris, France.
authors.forename: Patrick A D
authors.initials: PAD
authors.lastname: Grimont
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000907:Antibodies, Bacterial / Q000276:immunology; D015373:Bacterial Typing Techniques; D016172:DNA Fingerprinting; D004251:DNA Transposable Elements / Q000235:genetics; D004405:Dysentery, Bacillary / Q000382:microbiology*; D004768:Enterotoxins / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005602:France; D005838:Genotype; D006801:Humans; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D021521:Ribotyping; D012703:Serotyping; D012761:Shigella boydii / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D000907:Antibodies, Bacterial; D004251:DNA Transposable Elements; D004768:Enterotoxins; D037521:Virulence Factors