title: [Resistance to second-line anti-tuberculosis drugs among peruvian multidrug resistant Mycobacterium tuberculosis strains].
abstract: OBJECTIVE
  To determine the drug resistance profiles for quinolones: ciprofloxacin (CFX), ofloxacin (OFX), moxifloxacin (MFX), and gatifloxacin (GFX); and for injectables: kanamycin (KAN), amikacin (AMK), and capreomycin (CAP) in multidrug resistant (MDR) strains. We also investigated the correlation between mutations in rrs, tlyA and gyrA/B genes, and the in vitro resistance to the second-line anti-tuberculosis drugs.
  
  
  METHODS
  In this pilot study we selected MDR clinical isolates collected from June-December 2004 in the Tropical Medicine Institute "Alexander von Humboldt" (Lima, Perú). The Minimum Inhibitory Concentration (MIC) of CFX, OFX, MFX, GFX, KAN, AMK and CAP for 14 clinical isolates were determined and the sequences of rrs, tlyA and gyrA/B genes were analyzed by conventional PCR followed by sequencing.
  
  
  RESULTS
  We obtained valid results for 11 samples. Four isolates were resistant to injectable drugs, and in all the cases the MICs were; >120 µg/mL for KAN and >160 µg/mL for AMK and CAP. Only 2 isolates were resistant to OFX with MIC = 4 µg/mL. Sequencing results suggested that the mutation A1401T in rrs gene could be the molecular cause of the resistance to injectable drugs. In this study we did not find any mutation in tlyA and gyrA/B associated to resistance.
  
  
  CONCLUSIONS
  Our study suggests a possible association between the mutation A1401T in rrs and resistance to injectable drugs. However further studies should be done to confirm this hypothesis in Perú.
authors.affiliation: Instituto de Medicina Tropical Alexander von Humboldt, Lima, Perú
authors.forename: Francesca
authors.initials: F
authors.lastname: Barletta
authors.affiliation: Instituto de Medicina Tropical Alexander von Humboldt, Lima, Perú
authors.forename: Carlos
authors.initials: C
authors.lastname: Zamudio
authors.affiliation: Instituto de Medicina Tropical, University of Antwerp, Amberes, Bélgica.
authors.forename: Leen
authors.initials: L
authors.lastname: Rigouts
authors.affiliation: Instituto de Medicina Tropical Alexander von Humboldt, Lima, Perú
authors.forename: Carlos
authors.initials: C
authors.lastname: Seas
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D010568:Peru; D010865:Pilot Projects
chemical_list: D000995:Antitubercular Agents