Reasons why 50 patients did not meet the 2007 ATS/IDSA diagnostic criteria for <i>M</i>. <i>kansasii</i> disease.

*Two patients were diagnosed with mixed infection (M. avium complex and M. abscessus). **Pulmonary tuberculosis was demonstrated by the presence of an M. tuberculosis culture isolate or by polymerase chain reaction. †Of these patients, 18 (78%) underwent follow-up without antibiotic treatment for a median duration of 12.1 months (interquartile range 4.4–32.0 months). None of these patients developed M. kansasii lung disease. Reasons why 50 patients did not meet the 2007 ATS/IDSA diagnostic criteria for M. kansasii disease.