The Itchy Dog, Part 4: The Streamlined Diagnostic Approach

Sad dog

Michele Rosenbaum, VMD, DACVD

How a diagnostic work up to find the cause of the itch can help reduce anxiety and stress in allergic dogs and their owners

Commit to the diagnostic work-up to determine the true cause of your canine patient’s itchy skin. A diagnosis for the cause of allergic itch is crucial given that disease commonly starts at a young age and typically lasts a lifetime. When a diagnosis is made, a long-term, individual, sustainable treatment plan can be designed. Finding the cause of the pet’s itch can decrease the number of “flare fires” we must put out, “derm emergency” visits, and reliance on multiple treatments for control which can decrease compliance and increase caregiver burden, and may add to stress and anxiety in pets1-3 and their owners. Start by providing fast and effective itch relief first to build trust and greater probability for accepting the recommendation to pursue a work-up.

Follow a streamlined diagnostic approach that prioritizes making the pet comfortable and then addresses all the common causes of itch. The itch tracker resource available from www.ScienceofStrongerBonds.com (see “Resources” section) has two sides: a diagnostic work up guide for you to fill out that shows the streamlined diagnostic approach to owners as you discuss your customized diagnostic and treatment plan, and an itch tracker where owners can rate and track their dog’s itch level over time to see how well the diagnostic trials and treatments are working.

Stop the Itch. Give your patient immediate relief and give the owner peace of mind by using targeted anti-itch treatments from the beginning and throughout the diagnostic workup. This can help reduce anxiety and stress while starting the work-up, and help build the owners’ trust in the veterinary team.

  • Reach for APOQUEL® (oclacitinib tablet) first-line: APOQUEL starts reducing allergic itch within four hours4 and controls itch in 24 hours.5 Its short half-life6 gives you the ability to stop and start treatment, making it an ideal tool for use in a flea control or food trial and throughout the diagnostic workup.
  • Use CYTOPOINT® during the diagnostic process when faced with unique situations, such as a dog under 12 months of age, owners who travel or have busy schedules, a non-compliant owner, a difficult-to-pill dog, or dogs with serious infections, all of which may cause anxiety and be stressful for the owner. While CYTOPOINT is effective for itch relief in allergic dogs7, its variable duration of effect (4-8 weeks) may make it more difficult to assess the pet’s response to flea control or an elimination diet. Diagnostic trials will need to be extended beyond CYTOPOINT’s duration of efficacy.

Rule Out Parasites. Parasites like fleas and mites can be treated and eliminated; give yourself a chance to be a hero. Perform a thorough flea-combing, skin scrapings, and a trial of a broad-spectrum, highly effective parasiticidal therapy.8 Dogs with flea allergy or scabies are often 10/10 itchy and their severe, unrelenting itch may lead to distress and anxiety for the pet and the whole family. Always rule out parasites first!

Treat Skin Infections. Repeated infections on the skin and in the ears with Staphylococcal bacteria and Malassezia yeast are common in dogs with allergic skin disease. These organisms can trigger inflammatory cytokines, worsening itch and inflammation. Skin or ear cytology should be performed for every patient to verify the presence of infection and to help choose appropriate topical and systemic therapy.

Conduct a Food Trial. Consider food allergy and conduct an 8-week food trial for dogs with non-seasonal itch, where parasites have been ruled-out or treated. Recently, a series of evidence-based reviews compiled previous studies on food allergy.9-13 It is widely believed by pet owners that a grain-free diet is the best way to diagnose a food allergy. While it is possible for dogs to be allergic to wheat or corn, this only occurs in 13 percent and 4 percent of dogs, respectively, and animal proteins are more common allergens.10 Serum tests, hair tests, and saliva tests are not accurate for diagnosing food allergy.12 Studies show that many over-the-counter foods and treats contain ingredients not listed on the label.13-15 Recommend use of prescription hydrolyzed or novel protein diets made by reputable and well-known pet food companies for food trials.

Confirm Atopic Dermatitis. Once we diagnose atopic dermatitis by ruling out all the other causes of itch, then the choice of a long-term targeted anchor treatment for atopic itch and inflammation depends on owner lifestyle and the needs of that individual patient. An anchor treatment is a single, sustainable therapy that provides satisfactory control. It should be accepted by patient, manageable long-term for the owner, and achievable for most patients. The goal is a long-term plan to minimize flares to maintain comfort. You can reduce anxiety and stress for the pet owner by helping to design a long-term plan centered around a single anchor treatment that is sustainable and realistic for the pet and their caregiver.

Pursuing a diagnosis is the most efficient and cost-effective way for to help your itchy patients. When allergies are well managed, anxiety and stress can decrease for the whole family.

IMPORTANT SAFETY INFORMATION for APOQUEL: Do not use APOQUEL in dogs less than 12 months of age or those with serious infections. APOQUEL may increase the chances of developing serious infections and may cause existing parasitic skin infestations or pre-existing cancers to get worse. APOQUEL has not been tested in dogs receiving some medications including some commonly used to treat skin conditions such as corticosteroids and cyclosporines. Do not use in breeding, pregnant, or lactating dogs. Most common side effects are vomiting and diarrhea. APOQUEL has been used safely with many common medications including parasiticides, antibiotics and vaccines.
See full Prescribing Information at https://www.APOQUELdogs.com/APOQUEL_pi.pdf

This article was reviewed/edited by board-certified veterinary behaviorist Dr. Kenneth Martin and/or veterinary technician specialist in behavior Debbie Martin, LVT.

References

    1. Park S-H et al. Elevated cortisol content in dog hair with atopic dermatitis. Japanese Journal of Vet Res 2016;64(2):123-129.
    2. Virga V. Behavioral dermatology.  Vet Clin North Am Small Anim Pract. 2003 Mar;33(2):231-51, v-vi.
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    9. Olivry T, et al. Criticallyappraised topic on adverse food reactions of companion animals (1): duration of elimination diets. BMC Vet Res. 2015 Aug 28;11:225.
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    11. Olivry T, et al. Criticallyappraised topic on adverse food reactions of companion animals (3): prevalence of cutaneous adverse food reactions in dogs and cats.  BMC Vet Res. 2017 Feb 15;13(1):51.
    12. Mueller RS, et al. Criticallyappraised topic on adverse food reactions of companion animals (4): can we diagnose adverse food reactions in dogs and cats with in vivo or in vitro tests? BMC Vet Res. 2017 Aug 30;13(1):275.
    13. Olivry T, et al. Criticallyappraised topic on adverse food reactions of companion animals (5): discrepancies between ingredients and labeling in commercial pet foods.  BMC Vet Res. 2018 Jan 22;14(1):24.
    14. Raditic DM, et al. ELISA testing for common food antigens in four dry dog foods used in dietary elimination trials. J Anim Physiol Anim Nutr (Berl). 2011 Feb;95(1):90-7
    15. Okuma TA, et al. Identification of meat species in pet foods using a real-time polymerase chain reaction (PCR) assay. Food Control. 2015 April: 50:9-17.

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