Members of the genus Acinetobacter are nonmotile rods, 1-1.5µm in diameter, and 1.5-2.5µm in length, becoming spherical in shape while in their stationary phase of growth. This bacteria is oxidase-negative, and therefore, does not utilize oxygen for energy production. They also occur in pairs under magnification.
Acinetobacter spp. are widely distributed in nature, and are normal flora on the skin. Some members of the genus are important because they are an emerging cause of hospital acquired pulmonary, i.e., pneumoniae, hemopathic, and wound infections. Because the organism has developed substantial antimicrobial resistance, treatment of infections attributed to A. baumannii has become increasingly difficult, whereupon, the only drug that works on multi-resistant strains is colistin, which is a very toxic antibiotic.
