Neurolymphomatosis in a cat with diffuse neuromuscular signs including cranial nerve involvement

Abstract

This case report describes the clinical signs, electrodiagnostic findings, magnetic resonance imaging, cerebrospinal fluid results and histopathology in a cat with neurolymphomatosis. A 7-year-old domestic shorthair cat was presented for evaluation of subacute progressive signs of tetraparesis, ataxia and anorexia. Neurological examination was consistent with a diffuse neuromuscular localisation with cranial nerve involvement. Electrodiagnostic test results were suggestive of denervation due to axonopathy. Magnetic resonance imaging of the brain and cervical spinal cord showed severe enlargement and contrast-enhancement of both trigeminal nerves, brachial plexi and the right C2 and C3 spinal nerves. Cerebrospinal fluid cytology was consistent with lymphoma. Histopathology confirmed infiltration of malignant lymphoid cells in both trigeminal nerves, the spinal nerve roots of C6-T2, meninges and choroid plexi. Immunohistochemistry results were consistent with a diagnosis of T-cell lymphoma. Although not frequently observed, lymphoma is a differential diagnosis in cats with diffuse neuromuscular signs and/or cranial nerve deficits.