Are you seeing a cat in your practice with suspected brain disease? Let’s build a short differential diagnoses list for the brain! A 2026 article by Drs. Pisco and Gomes (doi/10.1177/1098612X251394770) outlined the most common causes for cats presenting to a neurologist in the UK for all reasons, but we’re going to focus on the intracranial differentials for now.
One hundred seventeen cats were identified with “brain” disease in their population. The majority of those (~72%) were localized to the forebrain. Brainstem localization was second (18%), followed by multifocal localization (8.5%) and lastly cerebellar disease (1.7%). Cats with “brain” localization most often had neoplasia as the end diagnosis (37%) but this was closely followed by idiopathic disease (idiopathic epilepsy and paroxysmal dyskinesia) in 34.2% of cases. Inflammatory or infectious diseases were least common.
Not surprisingly, older cats more commonly had neoplasia and younger cats had idiopathic and inflammatory disease. The key takeaway here is that idiopathic epilepsy is much more common in cats than we often think and therefore it should always be included on the differential list for a cat presenting with seizures and a normal inter-ictal neurologic examination. Perhaps reading that some cats were diagnosed with a paroxysmal dyskinesia (PD: 8%) surprised you. If so, you’re not alone. While probably under diagnosed, PD becoming more widely recognized as a cause of episodic motor movements with normal mentation. Videos are the best way to differentiate between these two episodic diseases in general practice. (I can help, too!)
What do you suppose the most common inflammatory disease in the brain was? If you guessed extension of otitis media/interna to the intracranial vault you’re correct! If THAT surprises you you’re also not alone! This study reinforced what many neurologists suspect (fear??); middle ear disease is under diagnosed in cats and MANY have intracranial extension by the time we diagnose it. Autoimmune or meningoencephalitis of unknown etiology (non-infectious meningitis) was noted in almost 16% of cats, which is also higher than a previous study. The median age of cats with MUO was 37 months (or about 3 years old). Toxoplasma, while still a cause of intracranial disease in cats, was not very common in this population of cats. What’s the take away for inflammatory disease? Remember MUO in young cats and don’t overlook extension of otitis media/interna.
What do you do if you suspect a cat has intracranial disease? I’m here to help. Reach out for a consult, and we can work on getting an MRI if needed.
Short but sweet today. Thanks for reading! I hope you have a safe 4th of July and I look forward to working with you soon!