Haemorrhagic myelomalacia in a cat with extradural T-cell lymphoma

Abstract

Myelomalacia is a term used to indicate the softening of the spinal cord, which results from ischaemic or haemorrhagic necrosis that can occur as a sequel to acute spinal cord injury. A 10-month-old, female, mixed breed domestic cat exhibiting neurological symptoms was referred for evaluation. Neurological examination revealed symptoms consistent with thoracolumbar syndrome. Initial radiographic examination detected no changes of the thoracolumbar spine. The cat received a palliative treatment with tramadol hydrochloride and prednisolone. The patient did not respond to the treatment and one month later presented with worsening of symptoms that progressed to non-ambulatory paraplegia. Radiographic examination was performed a second time and revealed a mass inside the spinal canal at the L1 and L3 vertebral levels. The animal died and was sent for post-mortem examination. The necropsy revealed a greyish-white epidural mass inside the spinal canal that was compressing the spinal cord at the L1 and L3 vertebral levels. The spinal cord between T2 and L3 was reddish and friable. The pancreaticoduodenal lymph node was enlarged. Histologically, the spinal cord mass and pancreaticoduodenal lymph node presented neoplastic lymphocyte proliferation, and haemorrhagic myelomalacia was observed in the spinal cord from T2 to L3. Immunohistochemistry revealed that the neoplastic lymphocytes were positive for CD3 antibody (T-cell lymphoma), and the lymphoid organs showed immunostaining for feline leukaemia virus (FeLV). Haemorrhagic myelomalacia due to extradural lymphoma should be considered as a differential diagnosis in cats with spinal neurological signs. Key words: Cat. Spinal cord. T lymphocytes. FeLV. Immunohistochemistry. ResumoMielomalácia é um termo utilizado para indicar amolecimento da medula espinhal, decorrente de necrose isquêmica ou hemorrágica que pode ocorrer como sequela de lesão medular aguda. Um felino doméstico, sem raça definida, fêmea, 10 meses de idade, com sintomas neurológicos foi avaliado. O exame neurológico constatou sinais clínicos compatíveis com síndrome toracolombar. Na primeira avaliação, no exame radiográfico não foram observadas alterações na coluna vertebral toracolombar. respondeu ao tratamento e um mês após a primeira avaliação clínica, apresentou piora do quadro clínico apresentando então paraplegia não ambulatória. No segundo exame radiográfico foi observada uma massa radiopaca no interior do canal vertebral, comprimindo a medula espinhal entre L1 e L3. O felino veio a óbito e encaminhado para exame post-mortem. Na necropsia, foi observada no canal medular a presença de uma massa branco-acinzentada, extradural, comprimindo à medula espinhal no segmento entre as vértebras lombares L1 e L3. A medula espinhal entre T2 até L3 estava hemorrágica e friável. O linfonodo pancreaticoduodenal estava aumentado. Na avaliação histológica, a massa observada no canal medular e linfonodo pancreaticoduodenal apresentaram proliferação de linfócitos neoplásicos e a medula espinhal entre T2 e L3 apre...

Clinical and pathological aspects of bovine lymphoma affecting the spinal cord

“…This alteration occurs frequently in dogs and is usually associated with extramedullary pressure, as in intervertebral disc disease (Lahunta & Glass 2009). Lymphoma as a cause of hemorrhagic myelomalacia was previously described in horses (Rousseaux et al 1989), cats (Laisse et al 2017) and dogs (Zilio & Arias 2013), but to the best of our knowledge, there have been no reports in cattle. The hemodynamic disturbances caused by epidural compression generate vascular stasis, blood perfusion failure, plasma protein extravasation, increased colloid osmotic pressure and consequent edema (Vandevelde et al 2012).…”

Feline lymphoma in the nervous system: pathological, immunohistochemical, and etiological aspects in 16 cats

“…Hemorrhagic myelomalacia, described in three cases, is a neurovascular disorder from a secondary compressive medullar injury related to extradural masses (De Lahunta & Glass 2009). In cats this lesion associated with extradural lymphoma has been poorly reported (Laisse et al 2017).…”