title: Isolation of non-tuberculous mycobacteria among patients with pulmonary tuberculosis in Ontario, Canada.
abstract: OBJECTIVE
  There are limited data regarding the frequency and significance of co-isolating pulmonary non-tuberculous mycobacteria (NTM) in patients with pulmonary tuberculosis (PTB).
  
  
  METHODS
  We identified all patients with culture-proven PTB in Ontario, Canada, in 2004, identified those with NTM 'co-isolation' (≤6 months following initial TB isolate) and determined subsequent NTM isolation over 5 years.
  
  
  RESULTS
  In 2004, 369 people in Ontario had culture-proven PTB (average age 46 years, SD 21, 41% female). NTM co-isolation occurred in 11% (40/369), including Mycobacterium avium complex 22/40 (55%), M. xenopi 7/40 (18%), M. gordonae 6/40 (15%) and others 5/40 (13%). Patients with NTM co-isolation were older (55 vs. 45 years, P = 0.004), but had similar sex ratios (females 43% vs. 40%, P = 0.87). Among patients with co-isolation, 23% (9/40) went on to have ≥2 NTM cultures (excluding initial culture), compared with 3% (10/329) in the PTB group (including initial culture, P = 0.0001). In the co-isolation group, the median (quartiles) number of samples collected for mycobacterial study was 6 (4-8) compared to 2 (1-4) in the PTB group (P < 0.0001).
  
  
  CONCLUSIONS
  The high frequency of subsequent NTM isolation among patients with NTM co-isolation during PTB may warrant follow-up for potential NTM disease.
authors.affiliation: University of Toronto, Department of Medicine, Toronto, Ontario, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Damaraju
authors.forename: F
authors.initials: F
authors.lastname: Jamieson
authors.forename: P
authors.initials: P
authors.lastname: Chedore
authors.forename: T K
authors.initials: TK
authors.lastname: Marras
mesh_terms: D000328:Adult; D000368:Aged; D000995:Antitubercular Agents / Q000627:therapeutic use; D001431:Bacteriological Techniques; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D015269:Mycobacterium avium Complex / Q000302:isolation & purification; D015270:Mycobacterium avium-intracellulare Infection / Q000453:epidemiology / Q000382:microbiology; D019912:Mycobacterium xenopi / Q000302:isolation & purification; D009170:Nontuberculous Mycobacteria / Q000187:drug effects / Q000302:isolation & purification*; D016017:Odds Ratio; D009864:Ontario / Q000453:epidemiology; D011379:Prognosis; D012189:Retrospective Studies; D013183:Sputum / Q000382:microbiology; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents