title: Hemorrhagic necrotizing splenitis in a slaughter pig infected with Arcanobacterium species.
abstract: A 6-month-old barrow presented with lethargy, inappetence and dysstasia. At necropsy, multiple coalescing hemorrhagic foci were detected in the margins of the spleen. Gram-positive bacilli were isolated from the spleen, kidney, muscle and liver. Comparative 16S rDNA gene sequencing analysis of the isolates (TO16177) revealed that they would be the same species of unpublished Arcanobacterium species strain HJ57-14E (accession no. gi 18873551) (99.7% similarity based on a comparison of 675 bp). Histologic examination of the splenic tissue sections revealed extensive necrosis and inflammation, and gram-positive bacilli were discernible. Multifocal necrosis was also detected in the liver. Immunohistochemically, the isolates were cross-reacted with polyclonal antibodies against Arcanobacterium pyogenes and Actinomyces naeslundii, and the reaction was strong for the latter. Similar reactions were found in the suppurative lesions of the tonsil, and occasionally in the spleen and lymph nodes. The present results indicate that the unpublished Arcanobacterium species induced multiple organ failure accompanied by acute hemorrhagic necrotizing splenitis in this growing-finishing pig.
authors.affiliation: Toyama Prefectural Meat Inspection Center, Imizu, Japan.
authors.forename: Takemi
authors.initials: T
authors.lastname: Ohba
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Shibahara
authors.forename: Hideki
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Masanori
authors.initials: M
authors.lastname: Kubo
authors.forename: Ariko
authors.initials: A
authors.lastname: Takashima
authors.forename: Shigenori
authors.initials: S
authors.lastname: Imai
authors.forename: Satoshi
authors.initials: S
authors.lastname: Murakami
authors.forename: Koichi
authors.initials: K
authors.lastname: Kadota
mesh_terms: D039903:Actinobacteria / Q000235:genetics / Q000302:isolation & purification*; D000818:Animals; D001483:Base Sequence; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D017809:Fatal Outcome; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment; D013158:Splenic Diseases / Q000382:microbiology* / Q000473:pathology / Q000662:veterinary*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology* / Q000473:pathology
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S