Outbreaks of conidiobolomycosis caused by Conidiobolus lamprauges in sheep in the state of Bahia, northeastern of Brazil

Abstract

The present work describes the occurrence of two conidiobolomycosis outbreaks in Santa Ines breed sheep, in the state of Bahia. The first outbreak (FO) occurred in a property located in Santo Estevao city, involving three animals, and the second outbreak (SO) occurred in a property in Entre Rios city, affecting one sheep. In both outbreaks, the clinical findings were characterized by progressive weight loss, dyspnea, and bloody serous nasal discharge. In the FO was also observed unilateral craniofacial asymmetry, associated with exophthalmia and epiphora of the right eye. Autopsies performed on the three FO sheep showed a large mass predominantly yellowish-white with red-black areas of the uneven surface, finely granular, moist and crumbly located in the ethmoidal region, invading the nasopharyngeal, choana, sinuses, retro bulbar region, who infiltrated the cribriform plate and reached the meninges. In two sheep of the FO, the mass reached the front portion of the brain. In SO sheep it was found, on the mucous membrane of the nasal vestibule, small red-black multifocal to coalescing nodules, with eroded surface and hyperemia of the nasal turbinates with hemorrhagic catarrhal secretion, and in the most rostral portion of nasal cavity, the mucosa had a irregular, wet, bleeding and red-black surface, with blackish gray and brownish areas, displaying partial focal destruction of nasal turbinates. Microscopic examination of granulomatous lesions revealed multiple areas of coagulation necrosis containing intense reaction of Splendore-Hoeppli associated with negative images of fungal hyphae and granulomatous inflammation. In all cases, the GMS and PAS staining showed numerous wide hyphae, with bulbous distension at one end. By PCR technique it was characterized Conidiobolus lamprauges by analysis of serum samples of two sheep and paraffin block lesions of one sheep. Immunohistochemical analyzes were positive for C. lamprauges in all animals. It can be proved, for the first time, the occurrence of nasopharyngeal / rhinocerebral and rhinofacial conidiobolomycosis infection by C. lamprauges in the state of Bahia.