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.