Aspectos epidemiológicos, clínicos e anatomopatológicos da infecção por Gurltia paralysans em gatos

Abstract

ABSTRACT.-Togni M., Panziera W., Souza T.M., Oliveira Filho J.C., Mazzanti A., Barros C.S. In the last 20 years, an unknown neurological disease affected cat populations in the Western Border Region of the State of Rio Grande do Sul, Brazil. The onset of the disease was characterized by tail paralysis, followed by progressive paraparesis in the pelvic limbs, difficulty in ambulation and proprioceptive ataxia. After long prolonged clinical courses (12-24 months), when then affected cats became severely paraparetic and start to develop pressure sores do to decubitus, they were destroyed by the owners. At necropsy there were variable degrees of skeletal muscle atrophy of the pelvic muscles and some degree of reddening of the meninges at the level of T10-L7, due to the presence of a myriad of small blood vessels, as a typical varicose lesion that resembled a vascular hamartoma. Histologically, such lesions consisted of distension of the subarachnoid space due to a collection of dilated, blood-filled, tortuous blood vessels the lumina of which were occasionally partially or completely occluded by thrombi. Those varices were randomly surrounded by a lymphocytic or granulomatous inflammatory infiltrate with small foci of mature eosinophils. In the lumina of these varicose venules cross and longitudinal sections of nematode parasites could be observed. Based on the morphology of these parasites, in their anatomical localization (meningeal blood vessels) and in the species (cat) affected the nematode was identified as Gurltia paralysans. This paper describes detailed aspects of the epidemiology, clinical disease and pathology of this intriguing feline myelopathy and the definitive diagnosis of the condition: Feline crural parasitic paraplegia, a disease first described in Chile in the 1930's and now, for the first time, in Brazil. RESUMO.-Nos últimos 20 anos, uma doença neurológica desconhecida acometeu populações de gatos da Região da Campanha do RS e tornou-se um desafio diagnóstico para os veterinários locais. Os gatos afetados desenvolviam inicialmente paralisia da cauda, seguida de paraparesia progressiva nos membros pélvicos, alteração da marcha, posição plantígrada e ataxia proprioceptiva. Após longos períodos de evolução clínica (12-24 meses), quando se tornavam marcadamente paraparéticos e começavam a apresentar escaras de decúbito, eram sacrificados pelos proprietários. Na necropsia, demonstravam graus variados de atrofia dos músculos pélvicos e algum grau de avermelhamento das meninges entre T10 e L7, devido à presença de miríades

Severe myelopathy with thrombophlebitis caused by Gurltia paralysans infection in a cat

“…Other clinical signs associated with this parasitism include pelvic limb ataxia, pelvic limb proprioceptive deficits, pelvic limb tremors, pelvic limb muscle atrophy, tail trembling, tail atony, and faecal and urinary incontinence (Gómez and others 2010, 2011, Alzate and others 2011, Guerrero and others 2011, Moroni and others 2012, Mieres and others 2013, Togni and others 2013). The duration of clinical signs usually ranges from 2 weeks to 48 months (Gómez and others 2010, Mieres and others 2013, Togni and others 2013). Neurological signs are typically associated with the neuroanatomical lesions observed in the postmortem examination and histopathological specimens (Mieres and others 2013).…”

“…No lesions associated with the brain, spinal nerves or peripheral nerves have been reported (Mieres and others 2013, Togni and others 2013). Parasites collected from congestive spinal veins at the affected spinal cord segments were identified as G paralysans .…”

“…Histologically, intravascular G paralysans nematodes and secondary congestion, thrombosis and thickening of the subarachnoidal vessels have been found in the meningeal veins of the spinal cord (Gómez and others 2010, Moroni and others 2012, Mieres and others 2013, Togni and others 2013). Mild smooth muscle hypertrophy, moderate adventitial fibroplasia and marked subintimal fibrosis of spinal cord venules (phlebosclerosis) have also been reported (Togni and others 2013). In some specimens, concentric thickening of the venule walls produces marked stenosis of the vessel lumen (Togni and others 2013).…”

“…Mild smooth muscle hypertrophy, moderate adventitial fibroplasia and marked subintimal fibrosis of spinal cord venules (phlebosclerosis) have also been reported (Togni and others 2013). In some specimens, concentric thickening of the venule walls produces marked stenosis of the vessel lumen (Togni and others 2013). Intraluminal papillary projections, with arboriform aspect to the interior of dilated venules have been interpreted as varicose lesions (venular varices) (Moroni and others 2012, Togni and others 2013).…”

“…The geographical distribution of G paralysans includes areas of Argentina, Colombia, Uruguay, Chile and Brazil (Alzate and others 2011, Guerrero and others 2011, Rivero and others 2011, Moroni and others 2012, Togni and others 2013). The nematode exhibits neurovascular tropism and is found primarily in the leptomeningeal and parenchymal veins of the spinal cord, mainly in the lumbosacral area.…”