Correlation of MRI with the Neuropathologic Changes in Two Cats with Bromethalin Intoxication.

Area of Science:

• Veterinary Neurology
• Toxicology
• Neuroimaging

Background:

• Multifocal neurological deficits in cats can stem from various causes, including toxic insults.
• Accurate and timely diagnosis is crucial for effective management of neurological diseases in felines.

Observation:

• Two cats presented with progressive multifocal neurological signs affecting the prosencephalon, vestibular system, and motor pathways.
• Magnetic Resonance Imaging (MRI) revealed widespread white matter T2 hyperintensity in the brain and spinal cord.
• Diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps indicated cytotoxic or intramyelinic edema.

Findings:

• Necropsy confirmed widespread spongy degeneration of the central nervous system white matter.
• Toxicologic analysis identified desmethylbromethalin, a metabolite of the rodenticide bromethalin, in liver specimens.
• Bromethalin intoxication, a cause of oxidative phosphorylation uncoupling, was diagnosed as the underlying etiology.

Implications:

• Bromethalin intoxication should be considered in cats with progressive multifocal neurological deficits.
• Advanced MRI sequences (DWI/ADC) are valuable tools for diagnosing spongiform leukoencephalomyelopathy and identifying cytotoxic/intramyelinic edema.
• This study highlights the utility of neuroimaging in diagnosing challenging toxicological cases in veterinary medicine.