MRI findings of neuronal ceroid lipofuscinosis in a cat

White, Crystal; Mortier, Jeremy; Verin, Ranieri; Maddox, Thomas; Goncalves, Rita; Sanchez-Masian, Daniel

A 2-year-old, 3.4 kg male neutered domestic shorthair cat presented to the University of Liverpool Small Animal Teaching Hospital with a 2 week history of progressive weight loss, altered mentation, blindness and suspected focal epileptic seizures. Relevant history included a single visit to the referring veterinary surgeon 6 months prior to presentation for nonspecific behavioural changes. On neurological examination, the cat's mentation was obtunded and disorientated. The menace response was markedly reduced bilaterally with intact pupillary light reflexes. Jaw clattering and hypersalivation were demonstrated intermittently, consistent with focal epileptic seizure activity. Stimulus resulted in hyper-reactivity and hypertonicity of all limbs, thus hindering a comprehensive neurological examination, including ophthalmological and visual assessment. Gait analysis was not possible owing to the cat's obtunded status and hyper-reactivity. The remaining general examination was unremarkable. Based on the clinical signs and limited neurological examination, a diffuse forebrain neurolocalisation was suspected. The main differential diagnoses for a 2-year-old cat with diffuse forebrain neurolocalisation included metabolic disease (lysosomal storage disease, thiamine deficiency, hepatic encephalopathy), infectious causes (feline infectious peritonitis, toxoplasmosis, bacterial meningitis), immune-mediated disease (meningoencephalitis of unknown origin), developmental disease (lissencephaly, microencephaly) and degenerative disease (neuroaxonal dystrophy and leukoencephalomyelopathy). Biochemistry, including fasting ammonia and preprandial bile acids, and haematology were within normal limits. Serological testing for feline leukaemia virus, feline immunodeficiency virus, feline coronavirus and toxoplasmosis were negative. Cerebrospinal fluid analysis, including total protein, total nucleated cell count and cytology, was unremarkable.