Shaker syndrome, also known as steroid-responsive tremor syndrome, is a neurological disorder that, like its name, indicates, courses with tremor. It is an acute process, of unknown etiology, which most frequently affects young and small breed dogs, although in practice it can occur in animals of any age and size.
If you want to know more about Shaker syndrome in dogs, as well as its symptoms and treatment, we recommend that you join us on the next article on our site, in which we will talk more in depth about this neurological disorder.
What is Shaker syndrome?
Shaker syndrome is an idiopathic cerebellitis, that is, an inflammatory process that affects the cerebellum and has an unknown aetiology.
This is an acute process that occurs more frequently in young dogsunder 5 years and in small dogs under 15 kg, although it can appear in dogs of any age and size.
As its name suggests, the predominant sign of this syndrome is tremor This is because the cerebellum is responsible, among other things, to coordinate movements. When the animal makes a movement, the decision is made by the brain, but it is the cerebellum that is in charge of redirecting the action. However, when the cerebellum is affected, it does not correct the actions and the movement that should be unique and fluid is “fractionated”, thus appearing the characteristic tremor of cerebellar pathologies.
Although the most accepted name at the veterinary level is “steroid-responsive tremor syndrome”, there are other names to refer to this pathology:
- “ Shaking White Dog Disease” or “Shaking White Dog Syndrome”: This name is due to the fact that the disease was originally detected in small breed white dogs, such as M altese or West Highland White Terriers. However, nowadays it is known that it can affect dogs of any size and color.
- Shaker Syndrome, for its English translation.
Symptoms of Shaker syndrome in dogs
As we have already mentioned, the predominant sign of this syndrome is tremor. Dogs affected by this disease show tremors, mild or severes, which can affect the whole body or only some regions, without apparently having any other problem of he alth.
Tremors are generally worse during times of stress or excitement and are reduced or even disappear when animals are relaxed and asleep. However, in the most severe cases, tremors can occur even when the animal is performing simple tasks, such as eating.
In addition to tremor, dogs with this syndrome may have other neurological signs such as:
- Spontaneous Nystagmus: Nystagmus is rapid, repetitive, involuntary movement of the eyes. Being positional means that it occurs with the head still, without the need for the dog to put his head in an abnormal position for him.
- Ataxia: incoordination.
- Dificulty to walk.
- Seizures.
Being an acute process, the clinical signs usually worsen during the first 2 or 3 days and from then on they remain stable until veterinary treatment is established.
Causes of Shaker syndrome in dogs
Although several possible etiologies have been proposed for this idiopathic cerebillitis in dogs, at present the exact cause remains unknownThere are hypotheses that suggest that the pathology has an immune-mediated basis (that is, that the dog's own immune system attacks the cerebellar tissue), given that it responds to immunosuppressive treatments. However, there are other authors who suggest that the syndrome has an infectious basis.
In any case, to date Shaker syndrome continues to be classified within idiopathic meningoencephalitis, which are those of unknown origin.
Diagnosis of Shaker syndrome in dogs
The diagnosis of tremor syndrome that responds to steroids is made by exclusion, ruling out any other alteration that may present with tremor in the dogs.
In particular, the diagnosis should be based on the following points:
- Medical history and anamnesis: the information provided by caregivers about tremor episodes is of great value, since it can allow ruling out some differential diagnoses. It can also be very helpful to record one of the tremor episodes.
- Clinical examination: with special emphasis on neurological examination in order to detect other neurological signs compatible with shaker syndrome.
- Laboratory tests: including blood and/or urine tests (to rule out hypoglycemia, electrolyte disturbances, poisoning, etc.) and diagnosis of infectious and parasitic diseases (such as canine distemper, neosporosis, toxoplasmosis, etc.).
- MRI: in order to detect possible lesions in the central nervous system, such as tumors, cysts, edema, etc.
- Cerebrospinal fluid analysis: without being diagnostic, is the test that provides the most informationIn this syndrome, the cerebrospinal fluid is characterized by an increase in protein and a moderate increase in cellularity (pleocytosis), with lymphocytes and/or neutrophils.
A definitive diagnosis of steroid-responsive tremor syndrome will only be reached after ruling out all causes of tremors in dogs, especially electrolyte disturbances, intoxications and infections
Treatment of Shaker syndrome in dogs
The treatment for tremors in dogs will depend on the cause that originates them. Thus, once Shaker syndrome has been diagnosed, treatment should be instituted, which is usually based on the administration of two drugs, alone or in combination:
- Corticosteroids: such as prednisone. As the name of the syndrome indicates, animals often respond to treatment with steroids (also called corticoids or corticosteroids).
- Benzodiazepines: such as diazepam. They help control symptoms, although 25% of dogs continue to have tremors.
Generally, signs begin to subside within a few days after starting treatmentAs the condition improves, the corticosteroid dose is reduced until reaching the maintenance dose that manages to control the clinical signs and, finally, until treatment is completely withdrawn.
Prognosis of Steroid-Responsive Tremor Syndrome in Dogs
The prognosis for dogs with Shaker syndrome is good. The majority of animals improve their symptoms a few days after starting treatment until the symptoms completely subside.
However, it should be noted that some dogs become worse when the dose is reduced or corticosteroid therapy is withdrawn, Requiring in these cases lifelong treatment to control the tremors. Therefore, it is essential to always go to the veterinary center and not self-medicate the dog.
