Clinician's Forum: Expert Views from a Roundtable on Atopic Dermatitis

Compliments of Elanco Animal Health.

• Paul Bloom, DVM, DACVD,DABVP (Canine and Feline), Owner, Allergy, Skin and Ear Clinic for Pets, Livonia, Michigan
• Terese DeManuelle, DVM, DACVD, Owner, Allergy & Dermatology Veterinary Referral Center, Portland, Oregon
• Wayne Rosenkrantz, DVM, DACVD, Animal Dermatology Clinic, Tustin, California
• Tiffany Tapp, DVM, DACVD, Owner, Veterinary Healing Arts, East Greenwich, Rhode Island
• William G. Ryan, BVSc, MBA, MRCVS, Moderator, Managing Director Ryan Mitchell Associates LLC, Westfield, New Jersey

From differentiating atopy from food and flea allergy to finding the treatment regimen that suits the individual patient, managing atopic dermatitis is an art. These experts impart their insights on how to achieve success.

Dr. Ryan: Let’s start with the primary presenting signs, additional to pruritus.

Dr. Tapp: Erythema, crusting, otitis, secondary infections, and all the secondary changes. By the time they get referred, they’ve typically had antibiotics or ear medications; or they’ve had poor hair regrowth or other chronic changes.

Dr. Bloom: Head shaking and ear scratching are up there with pruritus.

Dr. Ryan: What is your diagnostic procedure for referrals?

Dr. DeManuelle: We start with the history—it’s a bit of a detective process. After we have fleas taken care of and have some control of pruritus with corticosteroids, we talk to the owner about differentiating food allergy from atopic dermatitis. The seasonality of pruritic outbreaks would lead us to be more suspicious of atopic dermatitis. It is also important to talk to owners about over-the-counter versus prescription diets. If we’ve eliminated food allergy, we talk about atopic dermatitis, the treatments, prognosis, costs, and side effects.

Dr. Ryan: How do you prepare owners for managing this potentially lifelong disease?

Dr. Bloom: We discuss long-term therapy; what owners are able to do time-wise, emotionally, financially, physically. To encourage follow up, we have owners understand that this isn’t a cookie-cutter treatment. It takes time to find the treatment combination that addresses the patient’s specific issues. I present what we should do, could do, might do; the more we do, the more successful we will be. Rather than giving a menu of things owners are going to do, I ask them, “Is this something you can do? If not, you have to understand these can be the consequences.” So by engaging them in the discussion, compliance improves significantly.

Dr. Ryan: How do you initiate management of atopic dermatitis?

Dr. Rosenkrantz: The term we use is multimodal therapy. By using multimod-al therapy, you may reduce the risk for adverse reactions. ATOPICA® (cyclospo-rine capsules, USP) MODIFIED might work fantastic in one patient, while Apoquel® or glucocorticoids may work better in another. Often these options can be used during the induction phase of immunotherapy and then tapered during maintenance. Every case has to be evaluated and treated individually, remembering that we have a nice long list of medications in our toolbox.

Dr. Tapp: We treat any infection, heal the epidermis, and turn the T-cell down (with cyclosporine, oclacitinib, or allergy shots). And certainly recheck, recheck, recheck; we have to stay in contact so that if something is not working, they don’t just get lost and say, oh I tried that and it never worked.

Dr. Bloom: I want most dogs bathed and moisturized once or twice a week. Then we supplement the diet with fatty acids.

Dr. DeManuelle: Most of my patients initially need antipruritic therapy, especially during flares. Sometimes we can get Atopica to every other day. If they flare, we get them back to daily therapy. I use a short course of low-dose cortico-steroids when they can be used safely. We’re using Apoquel  too.

Dr. Tapp: Maintenance topical therapy is just part of my protocol for a healthy epidermis. For owners, I draw pictures of the skin like a brick wall, so they get a visual of what happens with absorption of the antigen and then T-cell release of cytokines and how that affects the skin. Then I show them how allergy shots or medications work on the T cell. When the brick wall is healthy, moisture is held in while bacteria and pollen stay outside. If  the wall isn’t healthy the bacteria can penetrate and create infection—it makes sense to them. When I draw my picture of the T cell releasing cytokines, I explain that I prefer not to use steroids because there are steroid receptors in every organ. So you can see steroids affect more than we want, whereas cyclospo-rine is more targeted to the T cell to reduce the cytokine release. I tell them that Atopica has a long history and a great safety record.

Dr. Bloom: A steroid is like a nuclear bomb. It wipes out the itching but does lots of collateral damage. Apoquel and Atopica are more targeted. I’ll explain that we’ve used Atopica a long time, and it has a very good safety record. Apoquel, so far in my hands, has also been safe. I’m comfortable using it for the short and intermediate term, but I’ll explain that we don’t know the long term record. 

Dr. DeManuelle: Clinically, I am a bit more comfortable with a short course of low-dosage glucocorticoid and Atopica because of the number of patients we have had on these medications. We know so much more about Atopica over the long term. We know about glucocor-ticoids and what they target on a molecular basis. 

Dr. Rosenkrantz: Glucocorticoids impact humoral and cell-mediated immunity, suppress antibody levels, and have side effects (polyuria, polydipsia, behavioral changes, others). Atopica specifically inhibits the calcineurin-mediated cytokine, which affects T-cell activation and prolifera-tion. It inhibits mast cell and IgE-medi-ated reactions. Apoquel inhibits Janus kinase-1 and -3. Its main target is IL-31—the cytokine that generates the neurologic itch signal to the brain. It also affects other interleukins, so has wider targeting.

Dr. Ryan: What’s your experience tapering the different drugs?

Dr. Tapp: With ATOPICA® (cyclosporine capsules, USP) MODIFIED, probably 10% to 15% stay on daily dosing; another 10% to 15% go to 2 to 3 days a week instead of every other day. Apoquel is fast-acting with a short half-life, so they tend to stay on it daily for the long term. I try to avoid steroids.

Dr. Rosenkrantz: Typically we begin the steroid taper immediately after we see a reduction in clinical signs.  In my experience Atopica patients can be tapered to every other day after 6 to 8 weeks, and 15% to 20% of those to every third day.

For Apoquel, there are a lot of different responses. Most dogs need daily administration. We’ve had several that didn’t do well when switched from twice-daily induction to once-daily.

Dr. Ryan: Should this be under your supervision, or can the client go back to the referring practice?

Dr. Rosenkrantz: Managing a  chronic atopic dog is an art. It can’t be “cook- booked.” The more experience you have managing these cases and their various permutations, you learn  to treat each case a little bit differently. Some practitioners are adept at that, but working hand in hand with a local specialist can be quite helpful.

Dr. Ryan: What about immuno-therapy?

Dr. Rosenkrantz: We focus on immunotherapy as a long-term option because of its overall safety and relative rate of success. I would estimate that 50% of our atopic dermatitis patients are on immunotherapy. We push it particu-larly in younger dogs due to its safety, frequency of administration, and due to 60% of cases having good to excellent results, with 5% to 10% cures. Although expense can be a factor with initial testing, over the long term it can be economical compared to drug options. Patients with more chronic, progressive skin changes often have a lower response rate, and some clients are just not interested in this therapy.

Dr. DeManuelle: In the past 2 years, the majority of our clients have opted for sublingual immunotherapy for their pets. Those patients appear to respond faster and with improved results over inject-able immunotherapy. Approximately 75% of patients respond very well.

Dr. Ryan: What’s your approach to managing flares?

Dr. Rosenkrantz: In flare-ups I do cytology for secondary infections or overgrowth of bacteria or Malassezia. These complicate cases and sometimes get confused as part of the allergies because they accelerate the pruritus. It’s paramount to get that case in the clinic and not do knee-jerk adjustments over the phone. 

For short-term relief, if the pruritus is not too intense, I try therapies like antihista-mines and fatty acid therapies—not particularly effective by themselves, but they can sometimes be combined with other therapies for milder cases. For flares with more intense pruritus, we look at steroids and oclacitinib. Some-times it is just increasing the frequency of a drug. For example, a dog on every other day Atopica with a flare-up may simply respond to adjusting to daily dosing for a period of time.

Dr. DeManuelle: It’s important to identi-fy methicillin-resistant staphylococcal infection if it rears its ugly head. For patients that flare on immunotherapy, we supplement with Atopica or Apoquel as appropriate. If I’ve tapered a patient’s Atopica dose to every other day, I bring them back to a daily dose during a flare.

Dr. Ryan: What follow-up monitor-ing do you recommend for a dog on long-term therapy?

Dr. Rosenkrantz: There isn’t any established monitoring protocol. Most of our immunosuppressive cases have initial lab work and then are seen every 6 months for follow-up bloodwork and urinalysis. For  Apoquel  we do our first evaluation at 3 months.

Dr. Tapp: I typically do bloodwork before starting Apoquel or Atopica. If it’s a dog less than 6 years old, I do bloodwork and urinalysis annually for Atopica, twice a year for mature dogs. Because I never saw problems, I stopped doing it every 6 months with young dogs. Apoquel is still new, so I’m testing all dogs every 6 months, just like I do with steroids.

Dr. Ryan: How do you gauge whether treatment is successful?

Dr. Tapp: Usually I try to get clinical signs reduced to mild. Sleeping through the night is important because owners are often really affected by their dogs’ pruritus. The sentence I most love to hear is “You gave me my dog back.” They play again, they sleep, their appetite is normal. They don’t stink. We aren’t trying to achieve zero pruritus; we’re trying to give them their dogs back.

Dr. Rosenkrantz: I tell clients that cure is a really bad four-letter word in veterinary dermatology. It is something that we achieve occasionally in certain diseases. But for allergic patients, cures are really not obtainable. One thing I emphasize at the first visit is that control is what we are looking for. No matter what we find will work for that particular patient, it is going to be something that will need to be done on an ongoing basis.

Dr. Bloom: I give owners 3 goals. 1: no infection. 2: least amount of medication. 3: tolerable itching—the most challeng-ing. No one has a problem describing if a dog is really itchy or itch-free—it’s the in-between that takes discussion, using the visual analog score during this discussion. I had a client tell me their dog was on the dining room table. I thought, “Oh no.” But to them it was great because he hadn’t done that for 2 years. The dog felt so good he was being bad again, and they were happy.

Dr. Ryan: We’ve talked about dogs but not cats.

Dr. Tapp: Many cats have undiagnosed secondary infections. Even though most are indoor pets, there might be a dog in the house that goes out, so flea control is huge.

Dr. Ryan: Would you do testing before putting a cat on long-term therapy? 

Dr Tapp: I do cytology and skin scrape at the first appointment.  Based on the history I may do intense flea control or food trial, then reassess.  If it doesn’t work we decide if allergy shots or Atopica for Cats is the best choice.

Dr. DeManuelle: I skin test cats, and recommend immunotherapy initially because they respond well. A lot of patients definitely benefit from remain-ing on a hypoallergenic diet. I use Atopica for Cats because I can taper the dose, depending on how the patient is doing and if they’re having a flare. We don’t have to worry about the lag phase, and can see a rapid response.

IMPORTANT SAFETY INFORMATION FOR ATOPICA® FOR CATS (cyclosporine oral solution, USP) MODIFIED 

As with all drugs, side effects may occur. Side effects of ATOPICA for Cats are generally mild and transient, and may not require cessation of treatment. Most common side effects are gastrointestinal signs, such as vomiting, weight loss, diarrhea and loss of appetite. Persistent, progressive weight loss may result in hepatic lipidosis, therefore monitoring of body weight is recommended. It is important for your cat to avoid exposure to Toxoplasma gondii during treatment with ATOPICA for Cats. Please see product insert for full prescribing information.

ATOPICA® FOR CATS (cyclosporine oral solution, USP) MODIFIED INDICATION ATOPICA for Cats is indicated for the control of feline allergic dermatitis as manifested by excoriations (including facial and neck), miliary dermatitis, eosinophilic plaques, and self-induced alopecia in cats at least 6 months of age and at least 3 lbs (1.4 kg) in body weight.

For use only in dogs. Keep this and all drugs out of reach of children. Capsules should not be broken or opened. Wear gloves during administration and wash hands after. Do not use Atopica in dogs with a history of neoplasia, reproducing dogs, or dogs with a hypersensitivity to cyclosporine. Atopica is a systemic immunosuppressant that may increase the susceptibility to infection and the development of neoplasia. Gastrointestinal problems and gingival hyperplasia may occur at the initial recommended dose. Safety and effectiveness has not been established in dogs less than 6 months or 4 lbs. Use with caution in dogs with diabetes mellitus or renal insufficiency, and with drugs that affect the P-450 enzyme system. The most common adverse events are vomiting and diarrhea. Please see product insert for full prescribing information.

ATOPICA® (cyclosporine capsules, USP) MODIFIED INDICATION

ATOPICA is indicated for the control of atopic dermatitis in dogs weighing at least 4 Ibs. (1.8 kg) in body weight.