title: [Shigella spp infections in children living in the Metropolitan Region, Chile, during summer of 2004-2005].
abstract: BACKGROUND
  Shigella spp is a frequent cause of diarrhea in children. Antimicrobials decrease the duration of diarrhea and pathogen excretion. However, the increasing resistance limits their therapeutic value.
  
  
  OBJECTIVE
  To study Shigella serotype distribution in the Metropolitan Region in Chile, and its relationship with severity of disease, antimicrobial resistance pattern and clonality.
  
  
  METHODS
  During summer 2004-2005, stool samples from children with diarrhea were collected in Cary Blair transpon medium and cultured. Shigella isolates were serotyped using monoclonal and polyclonal commercial antibodies. In vitro activity of ampicillin, amoxicillin/clavulanic acid, chloramphenicol, cotrimoxazol, nalidixic acid, ciprofloxacin, ceftriaxone and azythromycin was determined by minimal inhibitory concentration (MIC). Clonality was studied by pulsed-field gel electrophoresis (PFGE) using Xbal as restriction enzyme.
  
  
  RESULTS
  One hundred thirty nine Shigella strains were isolated (77 S sonnei and 62 S flexneri). S sonnei and S flexneri 2a serotypes were responsible for 95% of episodes. Children aged 2-4 years, showed a greater incidence of Shigella infections and 77% of episodes were treated on an ambulatory basis. High resistance levels were observed for ampicillin, cotrimoxazole, amoxicillin-clavulanic acid and chloramphenicol (67%, 60%, 56% and 45%, respectively). We found 11 resistance patterns and 61,2% of strains were multiresistant. There were multiple clones without a strict relationship with resistance patterns.
  
  
  CONCLUSIONS
  Shigella infections in Metropolitan Region in Chile are associated to a restricted number of serotypes, representing a clonal expansion associated to different antimicrobial resistant patterns.
authors.affiliation: Programa de Microbiología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile.
authors.forename: Christopher
authors.initials: C
authors.lastname: Hamilton-West M
authors.forename: Valeria
authors.initials: V
authors.lastname: Prado J
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Hormazábal O
authors.forename: Rosanna
authors.initials: R
authors.lastname: Lagos Z
authors.forename: Dona
authors.initials: D
authors.lastname: Benadof F
authors.forename: Carmen
authors.initials: C
authors.lastname: Mendoza N
authors.forename: Andrea
authors.initials: A
authors.lastname: Elgueta N
authors.forename: Cecilia
authors.initials: C
authors.lastname: Tapia P
authors.forename: Marcela
authors.initials: M
authors.lastname: C Fuentes D
authors.forename: Isabel
authors.initials: I
authors.lastname: Alvarez A
authors.forename: Mariluz
authors.initials: M
authors.lastname: Hernández E
mesh_terms: D000208:Acute Disease; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D002677:Chile / Q000453:epidemiology; D003967:Diarrhea / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004405:Dysentery, Bacillary / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008826:Microbial Sensitivity Tests; D012621:Seasons; D012703:Serotyping; D012720:Severity of Illness Index; D012760:Shigella / Q000187:drug effects / Q000235:genetics; D014505:Urban Population
chemical_list: D000900:Anti-Bacterial Agents