Pulmonary mycobacteriosis caused by rifampicin-resistant Mycobacterium szulgai

We describe a rare case of pulmonary mycobacteriosis infected with rifampic in (RFP)-resistant Mycobacterium szulgai that was successfully eradicated w ith clarithromycin (CAM) treatment. An 80-year-old man was admitted to our hospital with a 4-week history of high fever, productive cough and malaise. Chest roentgenogram showed an infiltrative shadow in the left lower lung f ield. Isolated bacteria from sputum were acid-fast bacilli and identified a s M, szulgai by the DNA-DNA hybridization method. Drug susceptibility tests showed resistance to RFP (MIC>100 mu g/ mi), Combined treatment with ethio namide, streptomycin and isoniazid based on the results of drug susceptibil ity tests resulted in clinical and radiologic improvement within two years. Additional treatment with CAM for another year resulted in complete eradic ation of the mycobacterium.