Veterinary Dermatology and Pruritus in Dogs

Another Piece of Veterinary CPD from The Webinar Vet- veterinary education made easy

In a recent veterinary webinar on The Webinar Vet I discussed pruritus in the dog, an important condition in veterinary dermatology which is quite common. So we’ll start with common differentials of pruritus. You see a dog coming in, and it is an itchy dog. What are those conditions that you first think of? Well, I’m not going to go into great detail about all these different conditions. Other veterinary webinars, will spend more time going into depth on conditions like atopy and flea allergies and so on.

Atopy is obviously a very common differential diagnosis. It’s a common disease that you’ll be seeing probably most days in practice. You know, the dog who is basically allergic to dust, dust mites being the most common thing; pollens, less so. Histories are important here. And atopy is really a diagnosis that we make by ruling out all those other conditions. We then may decide to take blood tests and do skin tests. And we usually do that because we’re then going to think about making the vaccine. So atopy is probably one of your top differential diagnoses there. And we know the sort of dogs we see, very red, erythematous, and itchy in the intertriginous areas, the neck, the feet, the armpits, the groin.

Flea allergy dermatitis is obviously another very common differential diagnosis. With cats people come in and they say, “My cat hasn’t got fleas.” And you can comb this cat as much as you want, and probably will never find a flea on it. – the reason being that it is grooming itself so well. In fact, flea allergic cats are much more able to get rid of fleas than non-flea-allergic cats. So you may never see a flea on this cat. And so people come in, and even vets say, Oh, well, we didn’t find any fleas. So therefore we didn’t treat. Any cat coming in with a dermatological problem, 90 percent of the time, fleas are involved. We need to be using something like Frontline once a month. I would think that’s a minimum database that we do. If we just send the cat away with Frontline and really drill into the owners that they must be doing it monthly, then that’s a great start.

Malassezia dermatitis is obviously also common. Often on top of the atopy, we also see dogs who, I think, are allergic to the malassezia, so even small numbers cause big problems. And, of course, staphylococcalpyoderma will cause pruritus. Quite often that’s a secondary problem. So when we get rid of the infection, we then need to dig deeper and say, Well, what else has been going on? And quite commonly, if the dog is still itching, you’re probably thinking about more allergic causes. If you stop the dog from itching by giving it a course of antibiotics, in perhaps an older dog, you’ve got to think about diseases like hypothyroidism or Cushings disease. It’s always a good idea to rule out all those other ectoparasites as well. A differential diagnosis that I never want to miss, because it just makes me look stupid if I do, is scabies.

And I’ve certainly had cases referred to me as an atopic dog that actual has the scabies mites. And if people have spent hundreds and hundreds of pounds on blood tests and skin tests and everything else, obviously they’ve got a little bit of a right to be a little aggrieved if I find a scabies mite, or take a blood test and discover there’s been a scabies infection, in half an hour or so. I think it’s a very important differential not to miss. You know, the history is very important. If you’re living in a very rural area where there are lots of foxes, please rule out this out when they get brought to you.