Before you scoff, I think there is such a thing as a dermatological emergency. If you agree or disagree, make a comment at the end of the blog.
I’m speaking at Abbey Veterinary Hospital’s annual CPD evening on Tuesday 10th November at a local hotel and I’m sharing my notes here. My slide presentation is up on slideshare so feel free to take a look at the slides.
My abiding memory of a definite derm emergency is of a very obviously Cushingoid dog being referred to me in the mid 90s. A diagnosis had not been made but a very decrepid-looking Staffie came to see me( they’re common in Liverpool). I could see it looked very poorly and asked the owner to put it on the table immediately as I was very concerned about it. As he lifted it up, the dog gasped out and sagged onto the table. It had died! That was probably past emergency.
However, what do I consider truly dermatological emergencies?
This is, thankfully, rare in small animal practice and often associated with hymenoptera stings. Depending on where on the body the pet is stung is also important on deciding on severity. Often an injection of dexamethasone may be the only treatment needed. Bee stings may be left inside the pet and may have some activity for several days so observation is important. When I start a course of desensitisation vaccine with an atopic dog I always discuss the risk of anaphylaxis but have never seen it in my career
The intensely itchy patient.I regularly see very itchy cats that can only be controlled with Buster collars and steroids. They are excessively grooming and may even make themselves bleed. It is not right to have a cat having to wear a Buster collar all its life so I often try to see if steroids can bring their itch under control. Cats are relatively resistant to steroid side effects and I feel happy to give 1-2mg/kg of prednisolone per day to see if we can reduce the itch. This may be necessary before diagnostic work is undertaken to improve the cat’s quality of life. As itch is brought under control and different causes are investigated the steroid dosage can be reduced to see the effect. Atopica may be a more useful long term solution but can take a few weeks to have an effect.
When I see an intensely itchy dog which steroids are not controlling, I think of 3 things
3. Adverse reaction to food
Scabies is the one we really mustn’t list. If in doubt, treat it with Stronghold or Advocate. It is difficult to support a colleague who has spent hundreds of pounds on allergy testing but has missed out a scabies trial. Don’t forget it.
Malassezia cases often initially are controlled with steroids but increasingly high doses of steroids fail to keep the dog comfortable. Be confident with your cytology and consider systemic and local treatment if the condition is serious.
Finally, the textbooks often say that food allergic pets do not respond to steroids. My experience is that sometimes they do and sometimes they don’t but always consider food allergy on your list of differentials in the pruritic patient.
The sick pet who has dermatological signs
Some pets present as unwell and have dermatological signs. A prime example of this is hepatocutaneous syndrome. The dog often presents unwell with crusting lesions on footpads and scrotum with erythema on face and feet. Biochemistry reveals abnormalities in liver enzymes and diagnosis is completed with a skin biopsy which shows a characteristic pathology.
Pemphigus foliaceous is an immune mediated skin disease causing clefting of the epidermis and pustular development. It can be seen in dogs and cats. Cytology will often reveal keratinocytes which have split off from their neighbouring keratinocytes; become more round and become acanthocytes.
This condition can be treated by prednisolone alone but it needs high doses 2mg/kg for dogs and upto 4mg/kg for cats. This can produce undesireable side effects. If the pet is unable to be controlled on lower dose eod therapy then other drugs like azathioprine or chlorambucil can be used.
Finally, I often have cases of epitheliotropic lymphoma referred to me as a referral. The history is often of a dog with skin problems for many years which suddenly worsens or paradoxically a dog with very little skin problems which suddenly develops an “allergy” late in life. These cases are referred to me because of the severity of the disease. Dogs often only last 4-6 months, although, treatment with lomustine, steroids or the tyrosine kinase inhibitor, masitinib. Clinical signs include erythema, scaling, nodules and depigmentation.
I think it is fair to say that we dermatologists do not have it as easy as some other vets think. The presentation can be found at www.slideshare.net