title: Risk factors for mortality in patients with pulmonary infections with non-tuberculous mycobacteria: a retrospective cohort study.
abstract: BACKGROUND
  Infections with non-tuberculous mycobacteria (NTM) represent an increasing problem. Their clinical relevance is still largely unknown as well as predictors for mortality in affected patients. The objective was to describe prevalence and clinical relevance of different NTM and to identify risk factors for mortality.
  
  
  METHODS
  Retrospective cohort study of 124 patients with NTM detection between January 2001 and December 2011. Clinical characteristics like symptoms and radiological appearance were assessed at presentation. The primary outcome was all cause mortality during the follow-up period. Univariate and multivariate survival analyses using Cox proportional hazard models were employed for statistical analysis.
  
  
  RESULTS
  Over the study period, the frequency of NTM isolation varied from 4 to 12 patients per year. Twenty-nine out of 124 patients (23%) had a clinically relevant infection, according to the criteria of the American Thoracic Society (ATS). Mycobacterium avium was isolated most frequently, but Mycobacterium kansasii, Mycobacterium malmoense and Mycobacterium xenopi had the highest clinical relevance. Symptoms were mostly diverse and non-specific. On radiology, cavities were observed more frequently than a nodular-bronchiectatic variant or consolidation. In 75% of all patients, follow up time was more than two years. Median survival was 6.5 years (95%CI = 2.7-10.3). Factors significantly influencing survival time were haemoptysis (HR = 0.2, 95%CI = 0.1-0.6) and a consolidation on imaging (HR = 5.1, 95%CI 1.4-18.2).
  
  
  CONCLUSIONS
  The presentation of an infection with NTM can be diverse and depends mainly on the causative NTM pathogen. The most important predictor for increased mortality is the radiological appearance of a consolidation.
authors.affiliation: Department of Respiratory Medicine, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ Maastricht, The Netherlands. Electronic address: ellisgommans@gmail.com.
authors.forename: E P A T
authors.initials: EP
authors.lastname: Gommans
authors.affiliation: Department of Respiratory Medicine, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ Maastricht, The Netherlands. Electronic address: pjotr_even@hotmail.com.
authors.forename: P
authors.initials: P
authors.lastname: Even
authors.affiliation: Department of Medical Microbiology, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ Maastricht, The Netherlands. Electronic address: k.linssen@atriummc.nl.
authors.forename: C F M
authors.initials: CF
authors.lastname: Linssen
authors.affiliation: Department of Medical Microbiology, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ Maastricht, The Netherlands. Electronic address: h.van.dessel@mumc.nl.
authors.forename: H
authors.initials: H
authors.lastname: van Dessel
authors.affiliation: Department of Respiratory Medicine, Atrium Medical Center, Henri Dunantstraat 5, 6419 PC Heerlen, The Netherlands. Electronic address: e.v.haren@atriummc.nl.
authors.forename: E
authors.initials: E
authors.lastname: van Haren
authors.affiliation: Department of Respiratory Medicine, Orbis Medical Center, Dr. H. van der Hoffplein 1, 6162 BG Sittard-Geleen, The Netherlands. Electronic address: mi.devries@orbisconcern.nl.
authors.forename: G J
authors.initials: GJ
authors.lastname: de Vries
authors.affiliation: Department of Respiratory Medicine, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ Maastricht, The Netherlands. Electronic address: a.dingemans@mumc.nl.
authors.forename: A M C
authors.initials: AM
authors.lastname: Dingemans
authors.affiliation: Department of Family Medicine, CAPHRI School for Public Health and Primary Care, Maastricht University Medical Center, P. Debyeplein 1, 6200 MD Maastricht, The Netherlands. Electronic address: d.kotz@maastrichtuniversity.nl.
authors.forename: D
authors.initials: D
authors.lastname: Kotz
authors.affiliation: Department of Respiratory Medicine, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ Maastricht, The Netherlands. Electronic address: g.rohde@mumc.nl.
authors.forename: G G U
authors.initials: GG
authors.lastname: Rohde
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality*; D009162:Mycobacterium avium / Q000302:isolation & purification; D019909:Mycobacterium kansasii / Q000302:isolation & purification; D009426:Netherlands / Q000453:epidemiology; D011379:Prognosis; D012141:Respiratory Tract Infections / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality*; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed
chemical_list: D000900:Anti-Bacterial Agents
keywords: Infection; Mycobacterium avium; NTM; Non-tuberculous mycobacteria