title: Fatal Erysipelothrix rhusiopathiae septicemia in two Atlantic dolphins (Stenella frontalis and Tursiops truncatus).
abstract: We describe gross, histopathologic, ultrastructural, immunohistochemical, and microbiologic features of acute septicemia by Erysipelothrix rhusiopathiae in an Atlantic spotted dolphin Stenella frontalis and an Atlantic bottlenose dolphin Tursiops truncatus. Generalized lymphadenomegaly and widespread hemorrhages were the most consistent macroscopic findings. Tricavitary effusion and icterus were noted in one individual. Histologically, all organs examined showed numerous variably sized bacillary bacterial emboli (Gram-positive; Ziehl-Neelsen-negative), typically associated with systemic congestion, edema, hemorrhages, and fibrinocellular thrombi. These bacteria were frequently intravascular, either extracellular or intramonocytic/macrophagic, and to a lesser extent, free within the interstitium of parenchymal organs. In both cases, microbiological analysis yielded E. rhusiopathiae. A primary anti-E. rhusiopathiae antibody created in mice from one of the strains isolated allowed positive immunohistochemical detection. Electron microscopy and dual immunohistochemistry with lysozyme and MAC387 antibodies confirmed the intramacrophagic location of the bacilli. E. rhusiopathiae, a known multispecies and zoonotic agent, should be considered as a potential etiologic agent in septicemia cases in free-ranging individuals of these dolphin species.
authors.affiliation: Veterinary Histology and Pathology, Institute of Animal Health, Veterinary College, University of Las Palmas de Gran Canaria, Trasmontana s/n, Arucas 35413, Las Palmas de Gran Canaria, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Díaz-Delgado
authors.forename: M
authors.initials: M
authors.lastname: Arbelo
authors.forename: E
authors.initials: E
authors.lastname: Sierra
authors.forename: A
authors.initials: A
authors.lastname: Vela
authors.forename: M
authors.initials: M
authors.lastname: Domínguez
authors.forename: Y
authors.initials: Y
authors.lastname: Paz
authors.forename: M
authors.initials: M
authors.lastname: Andrada
authors.forename: L
authors.initials: L
authors.lastname: Domínguez
authors.forename: A
authors.initials: A
authors.lastname: Fernández
mesh_terms: D000818:Animals; D050681:Bottle-Nosed Dolphin; D004888:Erysipelothrix / Q000302:isolation & purification*; D004889:Erysipelothrix Infections / Q000382:microbiology* / Q000473:pathology; D017809:Fatal Outcome; D018805:Sepsis / Q000382:microbiology / Q000662:veterinary*; D050706:Stenella