title: Rapid detection of Pseudomonas aeruginosa and Acinetobacter baumannii Harboring bla(VIM-2), bla(IMP-1) and bla(OXA-23) genes by using loop-mediated isothermal amplification methods.
abstract: BACKGROUND
  Carbapenem-resistant Pseudomonas aeruginosa (CRPA) and Acinetobacter baumannii (CRAB) are the leading causes of nosocomial infections. A rapid and sensitive test to detect CRPA and CRAB is required for appropriate antibiotic treatment. We optimized a loop-mediated isothermal amplification (LAMP) assay to detect the presence of bla(VIM-2), bla(IMP-1), and bla(OXA-23), which are critical components for carbapenem resistance.
  
  
  METHODS
  Two sets of primers, inner and outer primers, were manually designed as previously described. The LAMP buffer was optimized (at 2mM MgSO₄) by testing different concentrations of MgSO₄. The optimal reaction temperature and incubation time were determined by using a gradient thermocycler. Then, the optimized bla(VIM-2), bla(IMP-1), and bla(OXA-23) LAMP reactions were evaluated by using 120 P. aeruginosa and 99 A. baumannii clinical isolates.
  
  
  RESULTS
  Only one strain of the 100 CRPA isolates harbored bla(IMP-1), whereas none of them harbored bla(VIM-2). These results indicate that the acquisition of bla(VIM-2) or bla(IMP-1) may not play a major role in carbapenem resistance in Korea. Fifty two strains of the 75 CRAB isolates contained bla(OXA-23), but none contained bla(VIM-2) and bla(IMP-1) alleles.
  
  
  CONCLUSIONS
  Our results demonstrate the usefulness of LAMP for the diagnosis of CRPA and CRAB.
authors.affiliation: Department of Microbiology and Immunology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyung Sun
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Microbiology and Immunology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.|Institute for Immunology and Immunological Diseases, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae Myun
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Institute for Immunology and Immunological Diseases, Yonsei University College of Medicine, Seoul, Korea.|Department of Microbiology and Immunology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea. sangsun_yoon@yuhs.ac.
authors.forename: Sang Sun
authors.initials: SS
authors.lastname: Yoon
authors.affiliation: Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea. deyong@yuhs.ac.
authors.forename: Dongeun
authors.initials: D
authors.lastname: Yong
mesh_terms: D040981:Acinetobacter baumannii / Q000235:genetics / Q000302:isolation & purification*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial; D021141:Nucleic Acid Amplification Techniques; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000302:isolation & purification*; D012680:Sensitivity and Specificity
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems
keywords: Acinetobacter baumannii; Carbapenem resistance; Loop-mediated isothermal amplification (LAMP); Pseudomonas aeruginosa; bla(IMP-1); bla(OXA-23); bla(VIM-2)