Granulomatous lesions in multiple organs in a horse caused by Halicephalobus gingivalis

The present report describes the clinical, macroscopic and histologic findings associated with Halicephalobus gingivalis infection in a male Arab horse, in the state of Minas Gerais, Brazil. The animal presented with acute neurologic signs that quickly progressed to a comatose status. Due to the lack of response to therapy, rapid progression of signs and poor prognosis, the horse was euthanized. Post-mortem examination revealed large granulomatous nodules in the kidneys. Renal and internal iliac lymph nodes were enlarged and with loss of corticomedullary distinction. Histopathology revealed granulomatous encephalitis, nephritis, lymphadenitis and focal granulomatous pneumonia associated with marked and chronic infection caused by H. gingivalis. This is the first report of H. gingivalis infection in horses in Minas Gerais. H. gingivalis infection should be included in the list of differential diagnosis of equine neurologic diseases in the state of Minas Gerais.

Granulomatous lesions in multiple organs in a horse caused by Halicephalobus gingivalis

The present report describes the clinical, macroscopic and histologic findings associated with Halicephalobus gingivalis infection in a male Arab horse, in the state of Minas Gerais, Brazil. The animal presented with acute neurologic signs that quickly progressed to a comatose status. Due to the lack of response to therapy, rapid progression of signs and poor prognosis, the horse was euthanized. Post-mortem examination revealed large granulomatous nodules in the kidneys. Renal and internal iliac lymph nodes were enlarged and with loss of corticomedullary distinction. Histopathology revealed granulomatous encephalitis, nephritis, lymphadenitis and focal granulomatous pneumonia associated with marked and chronic infection caused by H. gingivalis. This is the first report of H. gingivalis infection in horses in Minas Gerais. H. gingivalis infection should be included in the list of differential diagnosis of equine neurologic diseases in the state of Minas Gerais.(AU)

Granulomatous meningoencephalitis due to Halicephalobus gingivalis in a horse

A 6-year-old, male, mixed-breed horse was presented for necropsy with history of blindness, ataxia, incoordination, peddling movements, nystagmus, depression, muscle spasms, abnormal appetite, mydriasis, abnormal behavior, and recumbency. There were no gross findings in the brain. Microscopically, there was meningoencephalitis characterized by a mild to moderate multifocal granulomatous inflammatory reaction, affecting mainly the cerebellum and, with lesser intensity, the thalamus and brain stem. Intralesional larval nematodes with morphology consistent with Halicephalobus gingivalis were observed. Based on the histopathological findings, a diagnosis of granulomatous meningoencephalitis by H. gingivalis was made.(AU)

Halicephalobus gingivalis (H.deletrix) in the brain of a horse

A 10-year-old Mangalarga gelding with rhabditiform nematode infection in the brain is described. Clinical signs were limited to circling and right side paralysis. Histological examination of the brain revealed marked gliosis and discreet edema. The perivascular mononuclear inflammatory infiltrate was composed of few layers of lymphocytes, plasmocytes and macrophages and rare eosinophils. The presence of rhabditiform nematodes was associated with the infiltrate. Areas of malacia associated with the parasites and parasite tracks with axonal spheroids were also seen close to the vessels and to the etiological agent and were more evident in the white matter. In the meninges there was moderate inflammatory infiltrate associated with perivascular parasites. The identification of the nematode was based on the histological examination of the cerebral fragments.

Um eqüino macho, com 10 anos, Mangalarga, apresentou uma infecção por um nematódeo rabditiforme no cérebro. Os sinais clínicos limitaram-se ao fato de o animal andar em círculos e apresentar paralisia do lado direito. O exame histológico do cérebro revelou acentuada gliose e discreto edema intersticial. O infiltrado inflamatório mononuclear perivascular era composto por poucas camadas de linfócitos, plasmócitos, macrófagos e raros eosinófilos, associados aos nematódeos rabditiformes. Áreas de malácia e trajetos com esferóides axonais são vistos ao redor de vasos e do agente etiológico, sendo mais evidentes na substância branca. Nas meninges, o infiltrado inflamatório foi moderado e associado a parasitas perivasculares. A identificação do nematódeo foi baseada no exame histológico do cérebro do cavalo.

Halicephalobus gingivalis (H.deletrix) in the brain of a horse

A 10-year-old Mangalarga gelding with rhabditiform nematode infection in the brain is described. Clinical signs were limited to circling and right side paralysis. Histological examination of the brain revealed marked gliosis and discreet edema. The perivascular mononuclear inflammatory infiltrate was composed of few layers of lymphocytes, plasmocytes and macrophages and rare eosinophils. The presence of rhabditiform nematodes was associated with the infiltrate. Areas of malacia associated with the parasites and parasite tracks with axonal spheroids were also seen close to the vessels and to the etiological agent and were more evident in the white matter. In the meninges there was moderate inflammatory infiltrate associated with perivascular parasites. The identification of the nematode was based on the histological examination of the cerebral fragments.

Um eqüino macho, com 10 anos, Mangalarga, apresentou uma infecção por um nematódeo rabditiforme no cérebro. Os sinais clínicos limitaram-se ao fato de o animal andar em círculos e apresentar paralisia do lado direito. O exame histológico do cérebro revelou acentuada gliose e discreto edema intersticial. O infiltrado inflamatório mononuclear perivascular era composto por poucas camadas de linfócitos, plasmócitos, macrófagos e raros eosinófilos, associados aos nematódeos rabditiformes. Áreas de malácia e trajetos com esferóides axonais são vistos ao redor de vasos e do agente etiológico, sendo mais evidentes na substância branca. Nas meninges, o infiltrado inflamatório foi moderado e associado a parasitas perivasculares. A identificação do nematódeo foi baseada no exame histológico do cérebro do cavalo.

Granulomatous meningoencephalitis due to Halicephalobus gingivalis in a horse

A 6-year-old, male, mixed-breed horse was presented for necropsy with history of blindness, ataxia, incoordination, peddling movements, nystagmus, depression, muscle spasms, abnormal appetite, mydriasis, abnormal behavior, and recumbency. There were no gross findings in the brain. Microscopically, there was meningoencephalitis characterized by a mild to moderate multifocal granulomatous inflammatory reaction, affecting mainly the cerebellum and, with lesser intensity, the thalamus and brain stem. Intralesional larval nematodes with morphology consistent with Halicephalobus gingivalis were observed. Based on the histopathological findings, a diagnosis of granulomatous meningoencephalitis by H. gingivalis was made.