title: Population structure of clinical Pseudomonas aeruginosa from West and Central African countries.
abstract: BACKGROUND
  Pseudomonas aeruginosa (PA) has a non-clonal, epidemic population with a few widely distributed and frequently encountered sequence types (STs) called 'high-risk clusters'. Clinical P. aeruginosa (clinPA) has been studied in all inhabited continents excepted in Africa, where a very few isolates have been analyzed. Here, we characterized a collection of clinPA isolates from four countries of West and Central Africa.
  
  
  METHODS
  184 non-redundant isolates of clinPA from hospitals of Senegal, Ivory Coast, Nigeria, and Central African Republic were genotyped by MLST. We assessed their resistance level to antibiotics by agar diffusion and identified the extended-spectrum β-lactamases (ESBLs) and metallo-β-lactamases (MBLs) by sequencing. The population structure of the species was determined by a nucleotide-based analysis of the entire PA MLST database and further localized on the phylogenetic tree (i) the sequence types (STs) of the present collection, (ii) the STs by continents, (iii) ESBL- and MBL-producing STs from the MLST database.
  
  
  RESULTS
  We found 80 distinct STs, of which 24 had no relationship with any known STs. 'High-risk' international clonal complexes (CC155, CC244, CC235) were frequently found in West and Central Africa. The five VIM-2-producing isolates belonged to CC233 and CC244. GES-1 and GES-9 enzymes were produced by one CC235 and one ST1469 isolate, respectively. We showed the spread of 'high-risk' international clonal complexes, often described as multidrug-resistant on other continents, with a fully susceptible phenotype. The MBL- and ESBL-producing STs were scattered throughout the phylogenetic tree and our data suggest a poor association between a continent and a specific phylogroup.
  
  
  CONCLUSIONS
  ESBL- and MBL-encoding genes are borne by both successful international clonal complexes and distinct local STs in clinPA of West and Central Africa. Furthermore, our data suggest that the spread of a ST could be either due to its antibiotic resistance or to features independent from the resistance to antibiotics.
authors.affiliation: Laboratoire d'Hygiène Hospitalière, UMR 6249 CNRS Chrono-environnement, Université de Franche-Comté, Centre Hospitalier Universitaire, Besançon, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Cholley
authors.affiliation: Laboratoire de Bactériologie, Centre Hospitalier National Universitaire de Fann, Dakar, Senegal.
authors.forename: Roughyatou
authors.initials: R
authors.lastname: Ka
authors.affiliation: Département d'Informatique des Systèmes Complexes, UMR 6174 CNRS, Université de Franche-Comté, Belfort, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Guyeux
authors.affiliation: Laboratoire d'Hygiène Hospitalière, UMR 6249 CNRS Chrono-environnement, Université de Franche-Comté, Centre Hospitalier Universitaire, Besançon, France.
authors.forename: Michelle
authors.initials: M
authors.lastname: Thouverez
authors.affiliation: Institut Pasteur, Abidjan, Ivory Coast.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Guessennd
authors.affiliation: Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Beniam
authors.initials: B
authors.lastname: Ghebremedhin
authors.affiliation: Institut Pasteur, Bangui, Central African Republic.
authors.forename: Thierry
authors.initials: T
authors.lastname: Frank
authors.affiliation: Laboratoire d'Hygiène Hospitalière, UMR 6249 CNRS Chrono-environnement, Université de Franche-Comté, Centre Hospitalier Universitaire, Besançon, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Bertrand
authors.affiliation: Laboratoire d'Hygiène Hospitalière, UMR 6249 CNRS Chrono-environnement, Université de Franche-Comté, Centre Hospitalier Universitaire, Besançon, France; Centre de Ressources Biologiques Ferdinand Cabanne - Filière microbiologie, Centre Hospitalier Régional Universitaire, Besançon, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Hocquet
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002488:Central African Republic; D007560:Cote d'Ivoire / Q000453:epidemiology; D005838:Genotype; D006801:Humans; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D009549:Nigeria / Q000453:epidemiology; D010802:Phylogeny; D011552:Pseudomonas Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D012675:Senegal / Q000453:epidemiology; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases