Pulmonary disease caused by Mycobacterium marseillense, Italy.

To the Editor: Mycobacterium marseillense was recently described as a new species belonging to the Mycobacterium avium complex (MAC) (1). We describe a case of pulmonary disease caused by M. marseillense in an immunocompetent patient. All strains isolated from the patient were preliminarily identified as M. intracellulare; however, a retrospective molecular analysis corrected the identification to M. marseillense.