ブラジル南部の屠殺牛における非定型寄生虫病変

Atypical parasitic lesions in slaughtered cattle in Southern Brazil.

• Welden Panziera
• Matheus Viezzer Bianchi
• Andréia Vielmo
• Ronaldo Michel Bianchi
• Saulo Petinatti Pavarini
• Luciana Sonne
• João Fábio Soares
• David Driemeier

抄録

本研究では，ブラジル南部の食肉処理場で診断されたサルコシスティス種によるヒダチドーシス，筋膜症，好酸球性筋炎の形態学的特徴と異常症状について報告した．牛から採取した27検体の非定型寄生虫病変を評価したところ，そのうち12検体が水疱瘡病，11検体が筋膜症，4検体が好酸球性サルコシスティス病であった．胞子嚢胞は主に心臓に認められ、すべての症例が左心室を侵していた。筋膜症は主に肺に発生し，小葉端部に結節性の隆起が認められた．また，3例に限局性トレマトデスが認められた．4例にサルコシストシスが認められ，主に骨格筋と心筋に病変が認められた．肉眼的には、局所的または局所的に広範な筋、パッチ、または多数の小結節が認められ、緑色がかったものから軽度の黄色がかったものまであった。組織学的には、すべての症例でサルコシスティスの内腔破裂性嚢胞が認められ、重度の好酸球性筋炎および心筋炎を合併していた。非定型部位に寄生した寄生虫病変および／または異常反応を示す寄生虫病変は，他の人獣共通感染症であると誤診される可能性があるため，速やかに発見されるべきである．

In this study, we described the morphological features and unusual presentations of hydatidosis, fasciolosis, and eosinophilic myositis caused by Sarcocystis species diagnosed at the slaughterhouse lines. Twenty-seven samples of atypical parasitic lesions from distinct cattle were evaluated, of which 12 corresponded to hydatidosis, 11 to fasciolosis, and 4 to eosinophilic sarcocystosis. Hydatid cysts were observed mainly in the heart, with all cases involving the left ventricle. Fasciolosis lesions involved mainly the lungs, and were characterized by a focal nodular elevated area involving the edges of the lobes. Intralesional trematodes were observed in three cases. Sarcocystosis lesions were observed in four cases, and lesions were primarily located in the skeletal and cardiac muscles. Grossly, they presented as focal or focally extensive streaks, patches, or numerous nodules that were greenish to mildly yellowish. Histologically, all the cases had intralesional ruptured cysts of Sarcocystis that were associated with severe eosinophilic myositis and myocarditis. Parasitic lesions in atypical locations and/or with aberrant responses should be promptly identified because it may mistakenly diagnosed as other potentially zoonotic diseases, such as cysticercosis and tuberculosis.