INFECTION of human beings by chromobacteria is a relatively rare occurrence. Hence, it has been of considerable interest in the past six months to observe in this hospital 11 cases of infection by these organisms, one of which had a fatal termination with bacterial endocarditis.
The chromobacteria have been described as nonsporulating, aerobic bacilli, usually motile and usually Gram-negative, producing yellow, red, or violet pigment which is generally insoluble in water. The bacteria are ordinarily saprophytic and are commonly found in water, soil, and sewage. They grow abundantly and with ease on ordinary mediums, and their most arresting feature is the pigment production, which occurs only in the presence of oxygen, usually only on solid mediums at suitable temperatures, and is most abundant on the primary culture.1 The chief member of the group producing a violet pigment is Chromobacterium violaceum, that of the group producing pink or red pigment