Conidiobolomycosis in Sheep in Brazil

Abstract

Abstract. Conidiobolomycosis is reported in the state of Piauí, in the semiarid region of northeastern Brazil. Affected sheep had depression, weight loss, serous or mucohemorrhagic nasal discharge, and cranium-facial asymmetry from exophthalmos of 1 eye, generally with increased volume of the eyeball, keratitis, and corneal ulceration. At necropsy of 60 sheep, friable masses were observed in the posterior region of the nasal cavity, often destroying the ethmoturbinate bones. Frequently, the lesions invaded the nasal sinuses, cribiform plate, orbit, and brain. The masses were irregular, granular with moist surfaces, and soft and friable with white, yellow, or tan coloration. Dissemination of the lesion to lungs was observed in 27 sheep, to the brain in 26, to lymph nodes in 3, to the kidney in 2, and to the gallbladder and heart in 1. The microscopic examination showed granulomatous inflammation composed of central necrosis surrounded by lymphocytes, epithelioid and giant cells, and fibrous tissue. In all lesions, negatively stained structures representing hyphae were surrounded by Splendore-Hoeppli material. Coagulative necrosis, thrombosis, and vasculitis were also observed. Grocott methenamine silver stain showed 8-30-mm-thick hyphae, rarely septate or ramified, irregular in shape, and with black contoured wall, sometimes with bulbous dilatation in the extremities. On electron microscopy, the hyphae had a thick double wall surrounded by cellular remnants and an inflammatory exudate. Conidiobolus coronatus was isolated from the lesions of 6 sheep. Conidiobolomycosis is an important disease of sheep in the state of Piauí, and other regions of northeastern Brazil.

Epidemiological, clinical and diagnostic aspects of sheep conidiobolomycosis in Brazil

“…An irregular nodular proliferation obstructing the choanae, as well as infiltration of the cribriform plate and eye socket causing the protrusion of the eyeball were also reported. Lesions spread to the brain, lungs, lymph nodes, kidneys, heart, and gallbladder were noticed (SILVA et al, 2007b;RIET-CORREA et al, 2008;BOABAID et al, 2008;FURLAN et al, 2010;MENDONÇA et al, 2012). RIET-CORREA et al (2008) reported the rhinofacial infection of sheep conidiobolomycosis in the Brazilian state of Paraíba.…”

“…With Gomori's methenamine silver stain of these lesions, numerous thick hyphae were observed. These structures were rarely septate, irregular in shape, with black contoured wall, sometimes with bulbous dilatation in the extremities (SILVA et al, 2007b;BOABAID et al, 2008;RIET-CORREA et al, 2008;FURLAN et al, 2010;MENDONÇA et al, 2012).…”

“…have hyaline, coenocytic hyphae or shorter hyphal bodies, although septa may be more infrequentthanl the older parts of the mycelium (CHAYAKULKEEREE et al, 2006). Rounded dilations are often seen at the ends of hyphae and these enlargements have been also described in case of conidiobolomycosis (KETTERER et al, 1992;SILVA et al, 2007b, BOABAID et al, 2008. These fungi are characterized by producing asexual spores, which are relatively large globose (CHAYAKULKEEREE et al, 2006).…”

“…Inside the granulomas there were negatively stained structures representing the fungal hyphae surrounded by abundant Splendore-Hoeppli material. The necrotic areas were often surrounded by inflammatory cells, particularly eosinophils, neutrophils, mononuclear cells, multinucleated giant cells, and epithelioid macrophages (SILVA et al, 2007b;BOABAID et al, 2008;RIET-CORREA et al, 2008). Estructures as Hypha could be observed within giant cells (SILVA et al, 2007b;MENDONÇA et al, 2012).…”

“…The necrotic areas were often surrounded by inflammatory cells, particularly eosinophils, neutrophils, mononuclear cells, multinucleated giant cells, and epithelioid macrophages (SILVA et al, 2007b;BOABAID et al, 2008;RIET-CORREA et al, 2008). Estructures as Hypha could be observed within giant cells (SILVA et al, 2007b;MENDONÇA et al, 2012). With Gomori's methenamine silver stain of these lesions, numerous thick hyphae were observed.…”