title: Photochromogenic and scotochromogenic mycobacteria: their clinical significance.
abstract: In the period 1973--1977, Mycobacterium tuberculosis was isolated by cultivation in 4408 cases from the clinical specimens of patients with positive X-ray findings. On the basis of atypical colony morphology or pigment formation, 263 other mycobacterial strains were identified: of these 23 were photochromogenic and belonged to Mycobacterium kansasii. The strains were cultured on several occasions from the specimens of 4 patients with broncho-pulmonary mycobacteriosis. The strains were resistant to isoniazid and streptomycin, sensitive to ethambutol and rifampicin. A total of 18 scotochromogenic isolates cultured from 14 patients with positive X-ray findings were identified as Mycobacterium aquae (M. gordonae) and its variants: strains showing slow Tween hydrolysis and 1 strain of rapid growth. In 5 cases M. tuberculosis was also obtained, indicating the presence of a mixed mycobacterial population. All scotochromogens were resistant to isoniazid and sensitive to ethambutol, with the exception of two strains sensitive to rifampicin.
mesh_terms: D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007958:Leukocyte Count; D008214:Lymphocytes; D009161:Mycobacterium / Q000302:isolation & purification*; D009165:Mycobacterium Infections, Nontuberculous / Q000276:immunology / Q000382:microbiology; D009170:Nontuberculous Mycobacteria / Q000302:isolation & purification* / Q000502:physiology; D010860:Pigments, Biological / Q000096:biosynthesis; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000382:microbiology*
chemical_list: D007136:Immunoglobulins; D010860:Pigments, Biological