The Impact of the 2007 ATS/IDSA Diagnostic Criteria for Nontuberculous Mycobacterial Disease on the Diagnosis of Nontuberculous Mycobacterial Lung Disease

Background: In 2007, the American Thoracic Society (ATS) and Infectious Disease Society of America (IDSA) published new diagnostic guidelines for nontuberculous mycobacterial (NTM) disease. Bacteriological criteria have become simpler compared to the 1997 ATS diagnostic criteria. Objective: For assessing the impact of the 2007 ATS/IDSA diagnostic criteria, we compared the diagnosis rate and time to diagnosis of NTM lung disease using the 1997 and 2007 ATS guidelines. Methods: Sixty-four patients who had excreted Mycobacterium intracellulare, M. avium, M. abscessus or M. kansasii at least one time in their respiratory specimens at Chonnam National University Hospital were reviewed. The 1997 ATS and 2007 ATS/IDSA guidelines were applied to these patients. Results: Thirty-seven of 64 patients (57.8%) were diagnosed with NTM lung disease by the 1997 ATS criteria. When the 2007 ATS/IDSA criteria were applied, 6 patients were newly diagnosed with NTM lung disease. The diagnosis rate significantly increased from 57.8 to 67.2% (p < 0.001). The time to diagnosis in the 1997 ATS and 2007 ATS/IDSA guidelines was 46.4 ± 53.0 and 36.2 ± 38.5 days, respectively (p = 0.002). Conclusion: These data suggest that we can shorten the time to diagnose NTM lung disease and diagnose more simply by using the 2007 ATS/IDSA guidelines. Further study will be needed to assess that these changes affect the management of NTM disease.