title: Isolation of Fusobacterium nucleatum and electron microscopic observations of spirochetes from tropical skin ulcers in Papua New Guinea.
abstract: Tropical ulcer is a disabling condition of the lower leg affecting mainly young adults and older children. Microscopic observations of lesion material have shown fusiform bacilli and spirochetes. We used anaerobic culture techniques to isolate and identify these fusiform bacilli. Electron microscopic (EM) studies were performed to characterize the spirochetes. Material collected on swabs was used to inoculate pre-reduced media and to prepare smears for gram staining; the swabs were placed in fixative for EM study. After incubation, colonies containing fusiform bacilli were subcultured. The anaerobic gram-negative fusiform isolates were identified as Fusobacterium nucleatum using biochemical reactions, hemagglutination testing, and reaction of antigen preparations of the isolates and ATCC strains in serological tests with rabbit antisera. EM observations of negatively stained spirochetes revealed an 8-16-8 periplasmic flagellar arrangement. F. nucleatum and spirochetes may participate in the pathogenesis of this polymicrobic infection.
authors.affiliation: Department of Microbiology, University of Maryland Dental School, Baltimore.
authors.forename: W A
authors.initials: WA
authors.lastname: Falkler
authors.forename: J
authors.initials: J
authors.lastname: Montgomery
authors.forename: R K
authors.initials: RK
authors.lastname: Nauman
authors.forename: M
authors.initials: M
authors.lastname: Alpers
mesh_terms: D000293:Adolescent; D002648:Child; D005673:Fusobacterium / Q000302:isolation & purification* / Q000648:ultrastructure; D005674:Fusobacterium Infections / Q000382:microbiology* / Q000473:pathology; D006386:Hemagglutination Tests; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010219:Papua New Guinea; D012883:Skin Ulcer / Q000382:microbiology / Q000473:pathology; D014208:Treponema / Q000648:ultrastructure*; D014211:Treponemal Infections / Q000382:microbiology* / Q000473:pathology