Today we are meeting Frank, a cat who had a strange behavioural incident at home, and how his vets investigated his behaviour. Now cat behaviour can often seem unusual from the outside – but in this case, it was critical that his owners sought veterinary attention early, rather than waiting to see what happened…

Meet Frank

Frank is a 4-year-old, male neutered DSH indoor cat who recently moved to the area from his previous vets. He was a very healthy cat with no other history apart from annual vaccinations. He lived with his brother, Benny, and though they generally got on, Benny did sometimes pick on Frank. His diet was consistent, and he had no toxin exposure. He was regularly treated for parasites. 

He first presented after having a strange incident that day – the owners heard Benny chase Frank into the bedroom, and then heard a crash. They ran to investigate and found Frank collapsed on the floor. He was gently paddling his feet, had passed urine, and may have been unaware of what was going on (unconscious). The event lasted a minute, though Frank remained wobbly for a few minutes after. The owners took him to their vet as soon as Frank was walking again. 

What Could Have Happened?

Based on the owner’s description, the vet believed there were a few possible causes of Frank’s behaviour. Their biggest worry was a traumatic brain injury, or TBI. This is where head trauma causes damage to the brain and increases the pressure inside the head. A severe TBI can result in loss of consciousness, poor breathing, and even death if left untreated. Did Frank hit his head while being chased by Benny?  

The vet’s other differential was a seizure – a seizure is caused by abnormal electrical activity within the brain that results in uncontrolled excitation of the neurones. Seizures typically cause muscle convulsions, full or partial loss of consciousness, urination and defaecation, and other behavioural abnormalities. Not all seizures are caused by epilepsy. Was Frank’s strange behaviour a seizure? 

Also possible was syncope, or collapse due to cardiovascular disease. In cats, this is commonly caused by heart disease, which is more common in older cats. It results in a heart that does not pump effectively; if the heart doesn’t deliver oxygen to where it is needed, primarily the brain and itself, it can lead to a sudden short loss of consciousness. This can sometimes lead to urination, defaecation and uncontrolled movement too, like seizuring. Does Frank have a heart condition?

Initial Examination

To distinguish between these three causes, the vet performed a thorough clinical examination. 

On examination, Frank was bright and well, happily exploring the room. He was not lame and appeared to walk normally. His pupils were normal sizes and his eyes reacted to touch and light normally. His gum colour was normal and his pulses strong. And his heart sounded normal and there was no heart murmur. On palpation, his abdomen was a little tender, but the vet believed this was due to anxiety. His temperature was normal. Frank was a little overweight (too much love, the owners said) but overall, a healthy cat. 

The vet’s biggest concern, a traumatic brain injury, was unlikely, given he had no neurological abnormalities. A classic symptom of TBI is irregular eye pupils, but Frank’s were normal. The other differential of a heart condition had not been fully ruled out, and the vet would need to perform an ultrasound and ECG of the heart to confirm this. However, heart disease was unlikely as Frank had no history of heart disease and was a young cat, and on examination his circulation and heart were normal. 

This left seizuring as the most likely cause of Frank’s behaviour. The vet discussed how they might investigate this further, but advised that since Frank was well, it was also acceptable to monitor him for now. Just like humans, cats can have single solitary seizures with no underlying cause and remain healthy. The owners opted to monitor Frank – before they left, the vet advised them on what to do if seizuring occurred again.  

Symptoms and Management of a Seizuring Cat

Seizures in cats may be full seizures or partial seizures. 

Full, or generalised seizures, affect the whole body. Full seizures usually involve collapse and unconsciousness, twitching or shaking of the muscles, salivation, urination and defaecation. There may be subtle behavioural changes before and after the seizure, such as salivation, growling, vision loss, pacing or catching invisible flies. 

Partial seizures are more common in cats – they affect only some parts of the body, which makes identifying them more difficult. Cats having partial seizures may twitch, growl, drool and walk strangely. They may be aggressive or dopey, and may hold their head or legs in odd positions. Partial seizures can progress to full seizures. 

The vet gave Frank’s owners the following advice should he seizure again: first of all, remain calm. Extra stimulation, such as a panicking owner, could prolong the seizure. Reduce stimulation further by drawing the curtains, turning off the lights, and talking calmly. A towel over the eyes can sometimes help too, as long as your cat can breathe properly. Only move your cat if they are in danger of hurting themself by hitting their head or legs, or by falling. Time the seizure, and try to video it if you can. The vet also dispensed some tubes of diazepam, a mild sedative – if Frank had a seizure again, the owners could insert the medicine into his bottom to try and stop the seizure. 

Seizuring can quickly become a life-threatening emergency – excessive movement raises the body temperature, which can severely damage cells. Extreme cases result in brain damage and death. If any seizure lasts longer than 5 minutes, is excessively violent, or if the animal comes in and out of seizuring with little recovery period (cluster seizures), veterinary help should be found immediately. 

Frank’s Neurological Exam

A few weeks passed, until a similar event happened again. Once more, Frank was being chased by Benny. This time, the owners saw what happened. Frank ran into a corner to hide then suddenly went rigid. He was definitely unconscious this time, urinated and foamed at the mouth. Luckily, the owners knew what to do, so dimmed the lights and kept calm. This event lasted around 30 seconds before Frank returned to consciousness, and fully recovered within a few minutes.

The owners saw their vet the next day and once again a basic clinical exam was performed, with nothing abnormal detected. A traumatic brain injury was extremely unlikely given the event had happened twice, and Frank’s heart remained normal. Thus, seizuring was still the most likely cause. 

The vet decided to perform a thorough neurological exam at this stage. The goal of a neurological exam is to identify any neurological abnormalities, and where the origin of the problem may lie. Cats are not always amenable to prolonged investigation, so some neurological exams must be shortened.

Neurological Exams in Cats

All neurological exams start with history taking – the vet had performed this on Frank’s first visit. Questions related to seizuring include access to toxins, changes to food, parasite and vaccine coverage, general health, and any other behavioural changes. 

After a clinical exam the vet looks at the cat’s mentation (mental function) and behaviour in a consult room – skilled vets can identify what is normal or abnormal cat behaviour. Muscle condition should also be assessed visually and by hand, as well as how the cat is moving – are they circling or falling over, are they weak, is their head tilted?

Next, we assess the cranial nerves. These are the nerves travelling to the head and neck that control senses like vision, facial sensation, tongue and eye movement and more. There are various tests we use to check these. If any cranial nerve has a deficiency, it may point to disease of the brain. 

Proprioception, or the control of limb placement, is important to check too. We can do this by seeing if your cat rights their paw when curled over, moving them on two legs, blindfolding them and touching the table with their legs, and other similar tests. Spinal nerves can be assessed by checking the skin sensation down the flanks, squeezing the paw, and checking head and neck movement. Other neurological tests may include checking bladder, anal and tail tones. 

At the same time, we will carry our full blood tests, to check for metabolic causes of seizures. Fortunately, Frank’s owners had him insured, and so there was no need to worry about the cost of the follow up tests – and if he was going to need MRI or CT scans, those to would be covered.

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Causes of Seizures in Cats

Frank’s neurological exam was also normal. Routine blood testing and blood pressure was normal. At this stage, his owners elected to start treatment for a presumed diagnosis of idiopathic epilepsy. However, there are many other causes of seizures in cats. We divide these into intracranial causes (inside the brain), and extracranial (outside the brain):

Extracranial causes in cats include toxins, liver disease, kidney disease, metabolic disorders like low calcium or glucose, high blood pressure, heart disease, and viral diseases like FIP, FIV and FeLV. Intracranial causes include encephalitis, structural brain disease, brain cancer, brain trauma, and idiopathic epilepsy. 

Idiopathic epilepsy is a chemical imbalance within the brain, possibly linked to genetics. This disease is less common in cats then in dogs, but anywhere from around 20-60% of seizuring cats has idiopathic epilepsy. It is more common in younger cats. Idiopathic epilepsy can only be diagnosed by ruling out other diseases. 

Investigation and Management of Epileptic Seizuring in Cats

Frank’s owners decided to start treatment after initial testing, but there are other steps that should be taken to formally diagnose idiopathic epilepsy.

The next investigative steps are performed under full general anaesthetic. This may start with chest radiography and ultrasonography to rule out heart disease. An MRI of the brain and spinal cord is crucial – an MRI will show them in superb detail. Samples of cerebrospinal fluid would also be taken from the back of the neck (CSF tap), to identify diseases like encephalitis. 

Should these tests all come back normal, idiopathic epilepsy would be a likely diagnosis. Epilepsy cannot be treated but can be managed with lifelong anti-seizure medication. The goal should be to reduce the frequency of seizures, ideally to one every 6 months or less, though this is not always possible. Regular examinations are important, as anti-seizure medication can put strain on the body. If advanced investigation is not possible, medication can be started, but may not be effective if another disease is present. 

How is Frank Getting On?

Frank is taking phenobarbital tablets twice a day. After some adjustment, based on the concentration of the drug in his body on a blood test, he has been seizure-free for almost a year. The owners are aware he will likely need this drug for the rest of his life but are happy that he is not having seizures anymore. He is not currently showing any side effects, and his vet checks him regularly. Benny still terrorises Frank on occasion, but Frank is otherwise a healthy happy cat again. 

Key Points:

  • Abnormal behaviour in cats can be caused by a variety of conditions, including seizuring
  • Seizuring in cats is often partial and subtle, but full seizures do occur
  • Diagnosing the causes of seizuring requires full history taking, clinical examination, neurological examination, blood pressure testing, blood parameter testing, an MRI, and CSF tap
  • The causes of seizuring can be extracranial or intracranial 
  • Treatment of seizuring depends on the underlying cause, but often requires anti-seizure medication
  • Idiopathic epilepsy is not uncommon in cats, and is often seen in younger cats – it can only be diagnosed after ruling out other causes of seizuring

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