Theodore K. Marras

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Population-based data have documented a worldwide increase in the prevalence of human nontuberculous mycobacterial (NTM) infections since 2000. Mycobacterium avium complex is predominant in North America and East Asia, whereas in regions within Europe, M kansasii, M xenopi, and M malmoense are more common. Host factors important to the current epidemiology(More)
BACKGROUND The prevalence of pulmonary non-tuberculous mycobacteria (NTM) infection is reportedly increasing. A study was undertaken of the "isolation prevalence" of pulmonary NTM in Ontario, Canada between 1997 and 2003 and the frequency of pulmonary NTM "disease". METHODS In a retrospective cohort, the "isolation prevalence" was studied by reviewing all(More)
BACKGROUND Severe Acute Respiratory Syndrome (SARS) became a global epidemic in 2003. Comprehensive information on 1-year outcomes and health care utilization is lacking. Research conducted during the SARS outbreak may help inform research planning for future public health emergencies. The objective of this study was to evaluate the 1-year outcomes in(More)
A significant knowledge gap exists concerning the geographical distribution of nontuberculous mycobacteria (NTM) isolation worldwide. To provide a snapshot of NTM species distribution, global partners in the NTM-Network European Trials Group (NET) framework (, a branch of the Tuberculosis Network European Trials Group (TB-NET), provided(More)
RATIONALE The prevalence of pulmonary nontuberculous mycobacterial (NTM) infections in the United States appears to be rising, but it is unclear if this is due to enhanced detection or actual increases in the burden of infection. Temporal changes in the epidemiology of Mycobacterium intracellulare sensitization may help explain recently observed trends in(More)
BACKGROUND The reported prevalence of pulmonary nontuberculous mycobacteria (NTM) infections is increasing. OBJECTIVE To determine the 'isolation prevalence' of NTM in 2007 and compare it with previously published research that examined the increasing rates of isolation of NTM from clinical pulmonary specimens between 1997 and 2003. METHODS Isolation(More)
OBJECTIVE Patients with rheumatoid arthritis (RA) are at increased risk of TB. Little is known about the risk of nontuberculous mycobacteria (NTM) disease in these patients. We sought to ascertain the rate of NTM infection and TB in all residents of Ontario, Canada, with and without RA. METHODS In a cohort study, all Ontarians aged ≥ 15 years in January(More)
INTRODUCTION The impact of pulmonary nontuberculous mycobacterial (pNTM) disease on health-related quality of life (HRQL) has not been quantified. METHODS We performed a prospective observational study of HRQL in 51 patients with pNTM disease. One generic (Short-form 36, version 2 -SF-36), and one pulmonary disease-specific instrument (St. George's(More)
In this case study, a 71 year old man with emphysema and severe rheumatoid arthritis, previously treated with a TNFα receptor antagonist, presented with progressive dyspnoea and weight loss. Thoracic imaging revealed extensive destruction of the left lung and this was associated with positive Mycobacterium xenopi cultures from respiratory samples.(More)