On the issue of pathogenicity b. Proteus is not clear enough. Most authors consider Proteus to be a conditionally pathogenic species. However, due to the widespread distribution of b. Proteus in nature and its ability to drown out the growth of other species on media must be approached with great caution in recognizing its etiological significance in each individual case. Indications of Proteus as the causative agent of local diseases are not so rare in the literature. Hauser in 1882 described a case of phlegmonous inflammation, in which the causative agent was b. Proteus and Streptococcus.
