title: Histopathological and molecular characterization of encephalitic listeriosis in small ruminants from northern Paraná, Brazil.
abstract: Listeriosis is a disease primarily of ruminants caused by the Gram-positive bacterium Listeria monocytogenes. Ruminants either demonstrate manifestations of the encephalitic, septicemic, or reproductive form of listeriosis. The pathological and molecular findings with encephalitic listeriosis in a 5.5-month-old, male, mixed-breed goat and a 3-year-old Texel-crossed sheep from northern Paraná, Brazil are described. Clinically, the kid demonstrated circling, lateral protrusion of the tongue, head tilt, and convulsions; the ewe presented ataxia, motor incoordination, and lateral decumbency. Brainstem dysfunctions were diagnosed clinically and listeriosis was suspected. Necropsy performed on both animals did not reveal remarkable gross lesions; significant histopathological alterations were restricted to the brainstem (medulla oblongata; rhombencephalitis) and were characterized as meningoencephalitis that consisted of extensive mononuclear perivascular cuffings, neutrophilic and macrophagic microabscesses, and neuroparenchymal necrosis. PCR assay and direct sequencing, using genomic bacterial DNA derived from the brainstem of both animals, amplified the desired 174 base pairs length amplicon of the listeriolysin O gene of L. monocytogenes. Phylogenetic analyses demonstrated that the strains associated with rhombencephalitis during this study clustered with known strains of L. monocytogenes lineage I from diverse geographical locations and from cattle of the state of Paraná with encephalitic listeriosis. Consequently, these strains should be classified as L. monocytogenes lineage I. These results confirm the active participation of lineage I strains of L. monocytogenes in the etiopathogenesis of the brainstem dysfunctions observed during this study, probably represent the first characterization of small ruminant listeriosis by molecular techniques in Latin America, and suggest that ruminants within the state of Paraná were infected by the strains of the same lineage of L. monocytogenes.
authors: Laboratories of Veterinary Pathology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, PR, Brazil.
authors: Selwyn Arlington
authors: SA
authors: Headley
authors: Molecular Biology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, PR, Brazil.
authors: Lívia
authors: L
authors: Bodnar
authors: Molecular Biology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, PR, Brazil.
authors: Juliana T T
authors: JT
authors: Fritzen
authors: Laboratory of Veterinary Pathology, Faculty of Veterinary Medicine, Universidade Norte do Paraná, Arapongas, PR, Brazil.
authors: Dalton Evert
authors: DE
authors: Bronkhorst
authors: Molecular Biology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, PR, Brazil.
authors: Alice Fernandes
authors: AF
authors: Alfieri
authors: Laboratory of Veterinary Pathology, Faculty of Veterinary Medicine, Universidade Norte do Paraná, Arapongas, PR, Brazil.
authors: Werner
authors: W
authors: Okano
authors: Molecular Biology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, PR, Brazil.
authors: Amauri Alcindo
authors: AA
authors: Alfieri
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics*; D001933:Brain Stem / Q000473:pathology; D001938:Brazil; D016000:Cluster Analysis; D005260:Female; D005838:Genotype; D015511:Goat Diseases / Q000382:microbiology / Q000473:pathology*; D006041:Goats; D006360:Heat-Shock Proteins / Q000235:genetics*; D006460:Hemolysin Proteins / Q000235:genetics*; D006651:Histocytochemistry; D008089:Listeria monocytogenes / Q000235:genetics; D008088:Listeriosis / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D008297:Male; D008590:Meningoencephalitis / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017385:Sequence Homology; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology / Q000473:pathology*
chemical_list: D001427:Bacterial Toxins; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins; C038705:hlyA protein, Listeria monocytogenes
keywords: Listeria monocytogenes; brainstem dysfunctions; epidemiology; listeriolysin gene; neuropathology; rhombencephalitis