An M. intracellulare, rough strain (serotype 7) has been isolated from sputum of a sixty-year old patients. This patient was a political prisoner in Germany between 1942-1945 and had contracted pulmonary tuberculosis with the cavity in the upper lobe of the right lung. A strain of mycobacterium susceptible to antituberculous drugs was isolated from his sputum in 1973. Since 1979, the isolation of M. Intracellulare has been accompanied by clinical signs of pulmonary mycobacteriosis, i.e. persistence of the cavity in spite of antituberculous treatments reapparition of cough with sputum, general weakness. Intradermo-reaction with specific sensitin gives a strong positive reaction, contrasting with a weak reaction with PPD tuberculin. As the antibiogram of the strain shows a susceptibility to cotrimoxazole and erythromycin, the patient underwent a therapy with the combination sulfamethaxozale-trimethoprime and erythromycin, for 4 months. At the end of this treatment, he seems to have recovered completely. The radiological aspect of the lungs remains unchanged. Although the source of contamination remains unknown, one thinks on the basis of bibliographica data, that it can be found in human beings, or seldom in animals (a pig, a bird) or in nature (a pond).