The Prevalence and Risk Factors for Nontuberculous Mycobacterial Infection in Lung Transplant Patients and Its Impact on Patient Survival and Graft Function

• Author / Creator

  Friedman, Daniel Z.P.

• Nontuberculous mycobacteria (NTM) are environmentally ubiquitous bacteria and frequent colonizers of immunocompetent and immunocompromised patients. NTM infections have been described in patients with chronic lung disease and post-lung transplantation. However, the risk factors for infection and its consequence on patient and graft outcomes are not consistently reported in the literature. NTM species are geographically diverse, and to date, there is a paucity of Canadian data, particularly in the transplant population. We sought to analyze data from a high-volume Canadian transplant centre to better characterize the local epidemiology of NTM infection, assess risk factors for infection, and determine the association between infection and patient and graft outcome.

  We performed a retrospective cohort study of 375 adult lung transplant recipients at the University of Alberta Hospital (Edmonton, Canada) between 2005 and 2014 to assess NTM epidemiology and risk factors. All positive NTM culture results in this cohort were extracted from the Provincial Laboratory database. The impact of NTM infection and colonization on patient and graft survival was tested by multivariate Cox regression analysis.

  NTM species were cultured from 26 (7%) patients before and 17 (4.5%) patients after transplant. The most commonly isolated species were Mycobacterium avium complex (55%) and Mycobacterium abscessus (20%). Five-year mortality was significantly higher in those infected with NTM after transplant (p=0.016), but there was no difference in chronic lung allograft dysfunction (CLAD) at 5 years (p=0.999). Cystic fibrosis and lower body mass index were both associated with pre-transplant, but not post-transplant, NTM infection.

  In this cohort, NTM isolation was associated with an increased risk of death but not CLAD onset at 5 years.

• Subjects / Keywords

  • Lung transplant
  • Mycobacterium avium
  • Mycobacterium abscessus
  • Chronic lung allograft dysfunction
  • Nontuberculous mycobacteria
  • Atypical mycobacteria

• Graduation date

  Fall 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-h87n-bz54

• License

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