Electron-microscopic observation of adherence of Acinetobacter baumannii to red blood cells.

It is now recognized that Acinetobacter spp. play a significant role in the colonization and infection of patients admitted to hospitals. The virulence factors of A. baumannii remains largery unknown. In this study, the adherence of A. baumannii to several species of red blood cells was investigated. The ruthenium red staining was used for electron microscopic studies. The results obtained in electron microscopy and the hemagglutination studies suggested that the thin and long fimbriae of A. baumannii participated in adhesion of these bacteria to red blood cells.