Unraveling the enigma of Spirocerca lupi infection in dogs: A hidden menace

Abstract

Spirocerca lupi is a nematode responsible for causing true malignancies in dogs. Esophageal nodular granulomas are pathological lesions of Spirocercosis. Spirocercosis is a disease occurring predominantly in Canidae, caused by the nematode Spirocerca lupi. The present case was noted in 3 years old German shepherd dog with esophageal nodular growth having neoplastic transformation following S. lupi infection was histologically elaborated with possible pathologic mechanism. Typical clinical signs are regurgitation, vomition and dyspnoea. Grossly, there was presence of round nodular masses on wall of esophagus occupied almost obliterating the whole lumen of the esophagus. On section, red-colored worms were noticed in the mass and were identified as Spirocerca lupi by parasitological examination. The nodular masses were processed routinely and stained by Hematoxylin and Eosin (H & E) and microscopically, esophageal mass revealed numerous parasitic eggs (Spirocerca lupi) encircled by proliferating fibrous connective tissue with infiltration of polymorphonuclear cells, predominantly eosinophils and histopathologic lesions of other organs were recorded.  Based on parasitic gross, microscopic and immunohistochemical evaluation, the case was diagnosed as Spirocercosis in the dog with acute renal failure.