Managing difficult dermatological cases in pets

hen it comes to difficult dermatology cases, owners are usually looking for an immediate and permanent fix. As veterinarians, we wish there were a “magic shot” that would offer relief to our patients and make our clients happy. However, before we reach for the imaginary magic shot, we must make sure to go back to the basics in terms of diagnosis and treatment.

It is easy to fall into the same conversations by offering medications such as lokivetmab (Cytopoint; Zoetis) and oclacitinib (Apoquel; Zoetis) for immediate relief, but we cannot forget to start at the beginning. Some owners walk into our exam rooms saying that they have tried everything. Sometimes this is true, but this is often not the case. We must remember to start with obtaining a thorough history. Begin by asking simple, open-ended questions that can sometimes lead to an easy diagnosis or direct us to diagnostics that are needed to help treat these cases.

Once you feel comfortable with the obtained history, you should next perform a thorough exam using an otoscopic examination. Remember, the ears are an extension of the skin. During the physical exam, you should start mentally creating a list of recommendations that include the basics, such as ear cytology, skin scrape, skin cytology, and/or tape preparations. These simple diagnostics can give us immediate answers to underlying issues. Furthermore, keep in mind that not all dermatology cases are secondary to allergies. Any case with chronic skin changes should have complete blood work with thyroid testing and urinalysis performed to rule out underlying endocrine issues.

Although in-house testing is relatively simple, quick, and less expensive, further diagnostics are needed to help determine the best course of treatment. There are several different types of cultures that can be used to identify specific microbial pathogens. For instance, dermatophyte test medium fungal cultures are used to isolate and identify dermatophyte organisms. Bacterial and fungal cultures are essential for prescribing appropriate topical and/or oral medications. Generally, any deep cellulitis-like lesions and/or draining tracts should be cultured for bacterial and fungal organisms. Aside from cultures, there are cases where we can obtain a lot of information from skin biopsies.

To improve diagnostic accuracy for the dermatopathologist, it is best to take 3 to 5 samples from a variety of lesions. Do not completely shave or aseptically prep the area. Use a 6-mm or 8-mm punch biopsy, rotate the punch biopsy tool in one direction to get the best cut, and be gentle—no crushing—with tissue forceps when transferring the sample to the formalin jar. Other diagnostics to consider are allergy testing, trichograms, polymerase chain reaction assays, or immunohistochemistries.

Because owners are looking for an immediate solution to their pets’ itching, lokivetmab and oclacitinib can be great medications to use while waiting for laboratory results. Oral antibiotics have the potential to create bacterial-resistant infections, we must be cautious with immediately prescribing oral antibiotics. We often forget that there are excellent topical medications, such as shampoos, mousses, wipes, and sprays, on the market that can help manage these cases while we wait for culture results. There are many benefits with the use of topical medications, which include physically removing allergens, reducing bacterial and yeast populations, repairing epidermal barrier defects, and antipruritic effects of cool water on hot, inflamed skin when bathing.

For patients in whom parasites and external causes have been ruled out, an elimination diet trial can be helpful. A proper food trial will be successful only if owners understand their pets must strictly adhere to the specific elimination diet. You will need to select a limited ingredient or hypoallergenic diet based on the diet history and the preferences of clients and patients. If a patient was given access to any other food or treats, the trial must start over. This includes rawhides, chew toys, flavored chewable medications, vitamins, and treats. An elimination diet trial for 8 weeks should be long enough for most patients that have a cutaneous adverse food reaction.

It can be easy to get tunnel vision when trying to diagnose and treat these cases, and we may forget there are specialists we can reach out to. Patients with skin conditions may be referred to a dermatologist at any time. If owners are willing to consult with a dermatologist, remember to contact their office before you refer the patient so you can discontinue medications that can interfere with diagnostics they would like to pursue. If owners decline a consult with a dermatologist or there is not one in your area, utilize teleconsultation.

In the end, we will not be successful with treating these cases if we do not take the time to educate clients. Managing difficult dermatological skin diseases takes time and clients must be on board with the cost of diagnostics, medications, food, and recheck appointments. Giving clients the tools and knowledge to better understand their pet’s skin problems will give them the power to know they can make a difference with their pet’s quality of life.