Recurrent septicemia in an immunocompromised patient due to probiotic strains of Bacillus subtilis

Bacillus subtilis is a gram-positive, aerobic, spore-forming soil bacterium ubiquitous in the environment. The beneficial effects of B. subtilis spores on the balance of the intestinal microflora is the rationale for its general use as a probiotic preparation in the treatment or prevention of intestinal disorders. B. subtilis spores are available in Italy as a pharmaceutical preparation for oral use. Each dose contains a mixture of 109 spores of four distinct antibiotic-resistant derivatives of ATCC 9799 (Enterogermina; distributed by Sanofi Winthrop, Milan, Italy) (1, 4) per vial. The pathogenic potential ofB. subtilis is generally described as low or absent (2). Data on the general importance of infections due to B. subtilis are incomplete, since it is a general practice of most microbiological laboratories to discard these strains or to report them as contaminants. Also, in the cause-of-death statistics of the World Health Organization no data on B. subtilis infections are present since, even if reported, they would be “invisible” at the international comparative level due to the coding used for classification of death causes (2a). In the literature, only a few cases of infections due to B. subtilis are reported (3, 6-8, 10) and only one retrospective study describes the isolation of antibiotic-resistant strains of B. subtilis (6).