Post-Traumatic Endophthalmitis Due to Acinetobacter radioresistens: Virulence Potential of Commensal Bacteria

Acinetobacter species are widely distributed in soil, water and hospital environment. In addition to A. calcoaceticus-baumannii complex, the clinically most relevant species, there are other genomospecies which are less frequently identified, mostly due to lack of accurate methods for routine identification. We describe the first case of post-traumatic endophthalmitis caused by otherwise non-pathogenic A. radioresistens, in India. Gram-negative coccobacilli were observed on Gram stain and culture of vitreous fluid specimen, and identified biochemically as Acinetobacter spp. The species was identified by Matrix Assisted Laser Desorption Ionization- Time of Flight Mass Spectrometry (MALDI-TOF MS). The pathogenic potential of ‘commensal’ A. radioresistens and its role in dissemination of carbapenem resistance genes underlines the importance of species-level identification in Acinetobacter infections.