title: Characterization of Leptospira interrogans serovar Pomona isolated from swine in Brazil.
abstract: BACKGROUND
  Leptospira interrogans swine infection is a cause of serious economic loss and a potential human health hazard. In Brazil, the most common serovars associated with swine infections are Pomona, Icterohaemorrhagie and Tarassovi. Cross-reactions among serovars and the failure of infected animals to seroconvert may complicate the interpretation of serological tests. Molecular methods with better discriminatory powers are useful tools for swine leptospirosis characterization and diagnosis.
  
  
  METHODS
  This study evaluated nine L. interrogans isolates from the States of Sao Paulo and Minas Gerais during different time periods. Isolates from diseased and apparently healthy swine were characterized by microscopic agglutination tests with polyclonal antibodies and were genotyped by VNTR, PFGE and MLST techniques. Broth microdilution was used to determine the minimal inhibitory concentration of the antimicrobials of veterinary interest.
  
  
  RESULTS
  The strains were identified as L. interrogans serogroup Pomona serovar Pomona Genotype A, while MLST grouped all of the isolates in sequence type 37. The PFGE analysis resulted in two pulsotypes with more than 70% similarity, distinguishing serovar Pomona isolates from the serovar Kennewicki reference strain. All of the isolates presented low MIC values to penicillin, ampicillin, ceftiofur and tulathromycin. High MIC values for fluoroquinolones, tiamulin, gentamicin, tetracyclines, neomycin, tilmicosin and sulfas were also observed.
  
  
  CONCLUSIONS
  All molecular techniques were concordant in L. interrogans serovar Pomona identification. This serovar may have a different antibiotic susceptibility profile than previously reported for Leptospira isolates.
authors.affiliation: Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Brasil. fmiragli@terra.com.br.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Miraglia
authors.forename: Luisa Z
authors.initials: LZ
authors.lastname: Moreno
authors.forename: Zenaide M
authors.initials: ZM
authors.lastname: Morais
authors.forename: Helio
authors.initials: H
authors.lastname: Langoni
authors.forename: Fabio H
authors.initials: FH
authors.lastname: Shimabukuro
authors.forename: Odir A
authors.initials: OA
authors.lastname: Dellagostin
authors.forename: Rudy
authors.initials: R
authors.lastname: Hartskeerl
authors.forename: Silvio A
authors.initials: SA
authors.lastname: Vasconcellos
authors.forename: Andrea Micke
authors.initials: AM
authors.lastname: Moreno
mesh_terms: D000372:Agglutination Tests; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001938:Brazil; D002353:Carrier State / Q000382:microbiology / Q000662:veterinary*; D005260:Female; D041401:Leptospira interrogans serovar pomona / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D007922:Leptospirosis / Q000382:microbiology / Q000662:veterinary*; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents