title: Suppurative otitis and ascending meningoencephalitis associated with Bacteroides tectus and Porphyromonas gulae in a captive Parma wallaby (Macropus parma) with toxoplasmosis.
abstract: A 6-year-old female Parma wallaby (Macropus parma) at a zoo in California developed acute ataxia and left-sided circling. Despite intensive care, clinical signs progressed to incoordination and prostration, and the animal was euthanized. At necropsy, the left tympanic cavity was filled with homogeneous suppurative exudate that extended into the cranium expanding the meninges and neuroparenchyma in the lateral and ventral aspect of the caudal ipsilateral brainstem and medulla oblongata. Microscopically, the brainstem showed regional severe suppurative meningoencephalitis with large numbers of neutrophils, fewer macrophages, and lymphocytes admixed with fibrin, necrotic cellular debris, hemorrhage, and mineralization, with numerous intralesional Gram-negative bacilli. Bacteroides spp. and Porphyromonas spp. were isolated on anaerobic culture from the meninges, and the bacteria were further characterized by partial 16S ribosomal RNA gene sequencing as Bacteroides tectus and Porphyromonas gulae. Bacterial aerobic culture from the meninges yielded very low numbers of mixed flora and Proteus spp., which were considered contaminants. Culture of Mycoplasma spp. from middle ear and meninges was negative. Additionally, Toxoplasma gondii cysts were detected by immunohistochemistry in the heart and brain, and anti-Toxoplasma antibodies were detected in serum. The genera Bacteroides and Porphyromonas have been associated with oral disease in marsupials; but not with otitis and meningoencephalitis. The results of the present work highlight the importance of performing anaerobic cultures in the diagnostic investigation of cases of suppurative otitis and meningoencephalitis in macropods.
authors: California Animal Health and Food Safety Laboratory System, University of California, Davis, CA (Giannitti, Anderson, Clothier)School of Veterinary Sciences, University of Buenos Aires, Buenos Aires, Argentina (Schapira) fgiannitti@ucdavis.edu.
authors: Federico
authors: F
authors: Giannitti
authors: California Animal Health and Food Safety Laboratory System, University of California, Davis, CA (Giannitti, Anderson, Clothier)School of Veterinary Sciences, University of Buenos Aires, Buenos Aires, Argentina (Schapira).
authors: Andrea
authors: A
authors: Schapira
authors: California Animal Health and Food Safety Laboratory System, University of California, Davis, CA (Giannitti, Anderson, Clothier)School of Veterinary Sciences, University of Buenos Aires, Buenos Aires, Argentina (Schapira).
authors: Mark
authors: M
authors: Anderson
authors: California Animal Health and Food Safety Laboratory System, University of California, Davis, CA (Giannitti, Anderson, Clothier)School of Veterinary Sciences, University of Buenos Aires, Buenos Aires, Argentina (Schapira).
authors: Kristin
authors: K
authors: Clothier
mesh_terms: D000818:Animals; D000836:Animals, Zoo; D016866:Bacteroidaceae Infections / Q000473:pathology / Q000662:veterinary*; D005260:Female; D007614:Macropodidae; D008590:Meningoencephalitis / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D010031:Otitis / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D017861:Porphyromonas / Q000302:isolation & purification*; D014122:Toxoplasma / Q000302:isolation & purification; D014124:Toxoplasmosis, Animal / Q000150:complications* / Q000175:diagnosis
keywords: Anaerobic bacteria; Bacteroides; Porphyromonas; Toxoplasma; brain; ear; infectious disease; marsupials; pathology