Clinicopathologic considerations of fusobacteria chorioamnionitis.

When sought by light microscopy in formalin-fixed tissue, fusobacteria are apparent in 7-18% of chorioamnionitis cases. Brown and Hopps bacterial staining characteristically visualizes their long, slender and filamentous forms. Fusobacteria-like organisms in placentae have previously been associated with prematurity. Our findings indicate that perinatal infection with fusobacteria may cause neonatal death from prematurity, rather than from sepsis. In a study of 586 placentae, 14 specimens with chorioamnionitis and fusobacteria-like organisms were found. On the five occasions when microbiologic tests were made, fusobacteria were isolated. Prematurity of the newborns was associated with twelve of those placentae. Immunofluorescent labelling of the organisms is a helpful but incomplete means of diagnosis. Because fusobacteria antibodies are highly specific, they do not cross-react with other members of the genus Fusobacterium. A typical case is reported, in detail.