title: A novel serovar of Shigella dysenteriae from patients with diarrhoea in Bangladesh.
abstract: Every year, around 3 % of isolates from patients with diarrhoea at Dhaka Hospital, ICDDR,B, are identified as Shigella-like organisms (SLOs) based on their activity in biochemical tests. These isolates do not react with any of the current Shigella antisera including all existing and provisional serotypes. Among these SLOs, a unique cluster of seven isolates with an identical plasmid profile was found and these isolates were further characterized by phenotypic and genotypic techniques. All were nonlactose fermenters, with an identical biochemical pattern typical of Shigella dysenteriae. They were classified as invasive since they harboured the 140 MDa invasive plasmid, were able to bind Congo red, produced keratoconjunctivitis in the guinea pig eye, and were positive by PCR for the ipaH gene and Shigella enterotoxin 2 [ShET-2] gene. All isolates were resistant to ampicillin, tetracycline and sulfamethoxazole-trimethoprim but were susceptible to mecillinam, nalidixic acid, ceftriaxone and ciprofloxacin. Six of the isolates were identical in DNA pattern by PFGE with the seventh exhibiting a closely related pattern; both patterns were distinguishable from all other Shigella and Escherichia coli patterns. An antiserum prepared against one of the isolates reacted with all isolates and did not cross-react with other Shigella and E. coli serotype reference strains. It is therefore proposed that these isolates represent a new provisional serovar of S. dysenteriae, type strain KIVI 162.
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Kaisar A
authors: KA
authors: Talukder
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Abdus S
authors: AS
authors: Mondol
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: M Aminul
authors: MA
authors: Islam
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Zhahirul
authors: Z
authors: Islam
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Dilip K
authors: DK
authors: Dutta
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Bijay K
authors: BK
authors: Khajanchi
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Ishrat J
authors: IJ
authors: Azmi
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: M A
authors: MA
authors: Hossain
authors: Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka 1000, Bangladesh.
authors: M
authors: M
authors: Rahman
authors: Laboratory of Enteric Pathogens, Health Protection Agency, Centre for Infections, Colindale, London NW9, UK.
authors: Thomas
authors: T
authors: Cheasty
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: Alejandro
authors: A
authors: Cravioto
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: G B
authors: GB
authors: Nair
authors: ICDDR,B: Centre for Health and Population Research, GPO Box 128, Dhaka 1000, Bangladesh.
authors: David A
authors: DA
authors: Sack
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000907:Antibodies, Bacterial / Q000378:metabolism; D000942:Antigens, Bacterial / Q000235:genetics; D015373:Bacterial Typing Techniques; D001459:Bangladesh; D003224:Congo Red / Q000378:metabolism; D003429:Cross Reactions; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D003967:Diarrhea / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial; D004405:Dysentery, Bacillary / Q000382:microbiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D004768:Enterotoxins / Q000235:genetics; D006168:Guinea Pigs; D006801:Humans; D007637:Keratoconjunctivitis / Q000382:microbiology; D010957:Plasmids; D012703:Serotyping; D012762:Shigella dysenteriae / Q000145:classification* / Q000302:isolation & purification* / Q000472:pathogenicity / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D004269:DNA, Bacterial; D004768:Enterotoxins; D003224:Congo Red