Atypical parasitic lesions in slaughtered cattle in southern Brazil

Abstract

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.

No presente estudo, são descritas as características morfológicas e as apresentações incomuns das lesões parasitárias de hidatidose, fasciolose e miosite eosinofílica por Sarcocystis spp., diagnosticadas nas linhas de abate. Foram analisadas 27 amostras de diferentes bovinos, das quais 12 correspondiam a casos de hidatidose, 11 de fasciolose e 4 de sarcocistose eosinofílica. Os cistos hidáticos foram observados predominantemente no coração, todos com localização no ventrículo esquerdo. As lesões de fasciolose envolveram principalmente os pulmões e eram caracterizadas por áreas nodulares e elevadas nos bordos dos lobos pulmonares. Trematódeos intralesionais estavam presentes em três casos. Lesões de sarcocistose foram observadas em quatro casos, com localização nos músculos esquelético e cardíaco. Macroscopicamente, observaram-se listras, manchas ou numerosos nódulos de coloração esverdeada a discretamente amarelada. Histologicamente, todos os casos apresentaram cistos intralesionais de Sarcocystis spp. rompidos e degenerados, associados à acentuada miosite e miocardite eosinofílica. A identificação das lesões parasitárias em locais poucos frequentes é de extrema importância, pois podem constituir diagnósticos diferencias de enfermidades zoonóticas, como cisticercose e tuberculose.