We have talked recently (and historically) about idiopathic head tremors (IHT) common in bulldog breeds. There is another head and neck tremor that has been less well described in the Doberman Pinscher dog termed “episodic head tremor syndrome”. This isn’t new, but a recent case made me realize that we hadn’t discussed this form of head tremors in a TidBit Tuesday before. It is high time.
I’m going to refer back to one of my favorite articles (reference: movement disorders, vol 26, No 13, 2011) as we talk about episodic head tremors of Doberman Pinscher dogs. (EHT-DPD) because I think it’s an oldie but a goodie.
What are episodic head tremors in Doberman dogs?
This is an inherited, idiopathic, paroxysmal movement disorder of Doberman dogs. The signs were traced back to 1 sire in the previously referenced study, strongly suggesting inheritance. Episodic head tremors could be a seizure disorder, just like dogs with presumed IHT may actually have a seizure disorder, but for the moment we still classify it as a movement disorder. Movement disorders do not typically associate with autonomic signs (drooling, vomiting, urinating, defecating) or reduced mentation (loss of consciousness) and should not occur during sleep or when the head is fully supported (like lateral recumbence). Those phenotypic descriptions can guide you in the direction of a movement disorder vs a seizure disorder however, as I tell clients, the best way to “know” is to have an EEG performed. That said, EEGs can be misleading, difficult to interpret or so full of background noise that they are uninterpretable. So, we do the best we can, but sometimes it comes down to our best guess for this diagnosis over a seizure. Although idiopathic, EHT-DPD in the referenced study, appeared frequently with concurrent stress. That could include pregnancy, heat, medications and surgery or illness. That doesn’t mean that stress causes this but may unmask it.
What do the tremors look like?
They are rapid, often intermittent, horizontal or vertical head shaking episodes. The oscillations are RAPID, not slow head swinging movements. There is a congenital form, occurring in dogs less than 1 year of age, and a later onset version.
What causes it?
It is idiopathic based on normal EEG, MRI, infectious disease screening, metabolic screening, and CSF analysis in the study mentioned above.
Should it be treated?
No, not usually. It doesn’t appear to be progressive in a negative manner. Breeding is not recommended for dogs exhibiting signs of EHT due to the suspected inherited manner.
Have you seen a case of EHT in your practice? How did it progress? Thanks for reading! I hope you have a good week. Stay tuned for more fun reading next week.