Summary 1. Bronchial involvement by tuberculoushilar nodes is a complication of primary tuberculosis which often leads to bronchiectasis later in life. Such late complication can be prevented by prompt bronchoscopic removal of the obstructing granuloma and the use of antibiotics. Two cases thus treated with success are reported. 2. Chronic nontuberculous infections of the lungs may simulate tuberculosis in symptomatology and roentgenogram appearance. A thorough history is important in the differential diagnosis. 3. Nonpathogenic acid-fast bacilli may be ingested with food and drink; therefore, finding of acid-fast bacilli in the gastric content does not necessarily mean tubercle bacilli. 4. With few exeptions, a persistentnegative tuberculin reaction is a strong evidence against active tuberculosis. Mere isolation of acid-fast bacilli from the gastric content of a tuberculinnegative child does not prove tuberculosis without a pathogenicity test of the organism. To avoid the risk of exposing a child to tuberculosis, admission of such cases to a tuberculosis hospital should be discouraged. 5. Not all acid-fast bacilli found inthe sputum are from the lung. A case is reported in which the nasal discharge was found to be the source of the acid-fast bacilli in the sputum.