Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Clinical Investigations Respiration 2011;82:124–129 DOI: 10.1159/000320254 The Impact of the 2007 ATS/IDSA Diagnostic Criteria for Nontuberculous Mycobacterial Disease on the Diagnosis of Nontuberculous Mycobacterial Lung Disease Dong-Ryeol Chae   a Yu-Il Kim   a Seung-Jung Kee   b Yoon-Hee Kim   a Su-Young Chi   a Hee-Jung Ban   a Yong-Soo Kwon   a In-Jae Oh   a Kyu-Sik Kim   a Soo-Ock Kim   c Young-Chul Kim   a Sung-Chul Lim   a Departments of a  Internal Medicine and b  Laboratory Medicine, Chonnam National University and Hospital, Gwangju, and c  Department of Internal Medicine, Seonam University College of Medicine, Namwon, Korea time to diagnosis in the 1997 ATS and 2007 ATS/IDSA guide- lines was 46.4 8 53.0 and 36.2 8 38.5 days, respectively (p = 0.002). Conclusion: These data suggest that we can shorten the time to diagnose NTM lung disease and diag- nose 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. Copyright © 2010 S. Karger AG, Basel Introduction Mycobacteria other than Mycobacterium tuberculosis complex and M. leprae are referred to as nontuberculous mycobacteria (NTM) [1]. NTM are environmental organ- isms found primarily in water, both natural and tap wa- ter, but are also found in soil, dust, animals and food [2, 3]. The increase in the prevalence of NTM infections in non-HIV patients has been observed over time in many countries, although there are regional differences in spe- cies distribution and clinical relevance [4–6]. In South Korea, the number of patients with clinical disease caused by NTM also continues to increase [7]. Key Words ATS/IDSA guidelines  Diagonosis rate  Nontuberculous mycobacterial lung disease Abstract Background: In 2007, the American Thoracic Society (ATS) and Infectious Disease Society of America (IDSA) published new diagnostic guidelines for nontuberculous mycobacte- rial (NTM) disease. Bacteriological criteria have become sim- pler 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 diagno- sis of NTM lung disease using the 1997 and 2007 ATS guide- lines. Methods: Sixty-four patients who had excreted Myco- bacterium 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 pa- tients. Results: Thirty-seven of 64 patients (57.8%) were di- agnosed 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 Received: April 13, 2010 Accepted after revision: August 9, 2010 Published online: October 8, 2010 Yu-Il Kim, MD, Department of Internal Medicine Division of Pulmonology and Critical Care Medicine Chonnam National University and Hospital, 8, Hak-dong, Dong-gu Gwangju 501-757 (South Korea) Tel. +82 62 220 6296, Fax +82 62 225 8578, E-Mail kyionly  @  chonnam.ac.kr © 2010 S. Karger AG, Basel 0025–7931/11/0822–0124$38.00/0 Accessible online at: www.karger.com/res