This organism was formerly called Citrobacter diversus. It is a straight rod occurring singly and in pairs. It is usually motile by peritrichous flagella. Gram reaction is negative. Gas is produced from sugars, and most strains do not produce hydrogen sulfide. It is an opportunistic pathogen found in feces of man and animals without any symptoms of disease, and in water, sewage, soil, and food. On rare occasion, it has been identified as the source for neonatal brain abscesses. Isolation from infected patients would typically be from cerebrospinal fluid, blood, and fluid exudates/pus. Growth is at 35-37 C.