title: Genetic variability of Mycobacterium tuberculosis complex in patients with no known risk factors for MDR-TB in the North-Eastern part of Lima, Peru.
abstract: BACKGROUND
  The aim of this study was to investigate the genetic diversity among Mycobacterium tuberculosis complex circulating in patients with no known risk factors for multi-drug resistant (MDR) tuberculosis (TB) living in a high MDR burden area and analyze the relationship between genotypes, primary drug resistance and age.
  
  
  METHODS
  Samples were collected during January-July 2009. Isolates were tested for drug susceptibility to first-line drugs and were genotyped by spoligotyping and the 15-loci Mycobacterial Interspersed Repetitive Unit (MIRU15).
  
  
  RESULTS
  Among the 199 isolates analyzed, 169 (84.9%) were identified in the SpolDB4.0 and 30 (15.1%) could not be matched to any lineage. The most prevalent lineage was Haarlem (29.6%), followed by T (15.6%), Beijing (14.1%), Latin American Mediterranean (12.6%) and U (8.5%). A few isolates belonged to the X and S clades (4.5%). Spoligotype analysis identified clustering among 148 of 169 isolates, whereas with MIRU15 all isolates were unique. Out of 197 strains; 31.5% were resistant to at least one drug, 7.5% were MDR and 22.3% showed any resistance to isoniazid.
  
  
  CONCLUSIONS
  In contrast with other Latin-American countries where LAM lineage is the most predominant, we found the spoligotype 50 from the Haarlem lineage as the most common. None of the prevailing lineages showed a significant association with age or resistance to isoniazid and/or rifampicin.
authors.affiliation: Instituto de Medicina Tropical Alexander von Humboldt, Molecular Epidemiology Unit - TB, Universidad Peruana Cayetano Heredia, Lima, Peru. francescabarletta@yahoo.es.
authors.forename: Francesca
authors.initials: F
authors.lastname: Barletta
authors.forename: Larissa
authors.initials: L
authors.lastname: Otero
authors.forename: Jimena
authors.initials: J
authors.lastname: Collantes
authors.forename: Belisa
authors.initials: B
authors.lastname: Asto
authors.forename: Bouke C
authors.initials: BC
authors.lastname: de Jong
authors.forename: Carlos
authors.initials: C
authors.lastname: Seas
authors.forename: Leen
authors.initials: L
authors.lastname: Rigouts
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000995:Antitubercular Agents / Q000494:pharmacology; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D010568:Peru; D011446:Prospective Studies; D018088:Tuberculosis, Multidrug-Resistant / Q000382:microbiology*; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents