M. Avium WGS During Mav-PD Treatment
This is a prospective observational study using whole genome sequencing (WGS) to investigate whether new strains (other than the initially identified strain(s)) of M. avium are responsible for persistently culture positive sputum during treatment (refractory disease), or the reversion to culture positive sputum after prior conversion to negative. The study will further investigate for differences between participants living in the Toronto/York region versus participants living elsewhere.

The primary goal of this prospective observational study is to understand why some patients with M. avium lung disease have persistent or recurrent M. avium in their sputum despite treatment. The aim is to understand whether it is usually due to treatment failure or new infection.
- EligibilityCriteria: Inclusion Criteria:  Age 18 and older Willing to provide informed consent and participate in study procedures Residing continuously in Ontario during the past five years Mav-PD, either initial or recurrent (previously treated patients will be eligible) five years Meet American Thoracic Society (ATS) / Infectious Diseases Society of America (IDSA) NTM disease criteria for Mav-PD  Exclusion Criteria:  Lack of an available pre-treatment M. avium isolate in the PHOL isolate bank The inability to produce sputum either spontaneously or by induction with nebulized hypertonic saline Cavitation >3 cm internal diameter Known macrolide-resistant MAC infection HIV infection Known diagnosis of cystic fibrosis History of solid organ or hematological transplantation Severe comorbid illness that is reasonably expected to limit survival to <24 months Residing in mid/north York region (King, Aurora, Newmarket, Whitechurch-Stouffville, East Gwillimbury or Georgina) Having moved between regions (Toronto/southern York region vs non-Toronto/York region vs mid-northern York region) within the past 5 years - Gender: All - MinimumAge: 18 Years - StdAgeList: Adult, Older Adult - StudyPopulation: Patients at the Toronto Western Hospital (TWH) Nontuberculous Mycobacterial (NTM) clinic who are to be initiated on therapy for Mav-PD. - SamplingMethod: Non-Probability Sample