Introduction
Dermatitis, cutaneous infections, and pruritus consistently are some of the most common reasons caregivers bring pets to veterinarians. They often have an underlying allergic primary disease process.
These symptoms may be chronic or recurrent; often presenting during the first as well as the last year of life. While a single etiology may be present, it is common that multiple diseases and factors are concurrent contributing issues. These factors may vary from episode to episode, season to season, year to year and with the general health of the patient. Canine atopic dermatitis is “A genetically-predisposed inflammatory and pruritic allergic skin disease with characteristic clinical features associated with IgE antibodies most commonly directed to environmental allergens” (Halliwell 2006). A somewhat similar disease occurs in cats and is referred to as “Feline Atopic Syndrome” (Foster 2014).A chronic, life impacting but nonlethal disease can be difficult for a caregiver to accept and challenging for the veterinarian-client relationship. In these situations, empathetic client communication, client engagement, and client education are essential for both the short- and long-term well-being of the patient (Knesl, Hart and Fine 2016). It is important for the veterinarian to “meet the client/caregiver where they are,” within their comfort zone, walk alongside them, and get to know their motivation, fears, goals, and limitations. Once the client is comfortable with the relationship, the veterinarian and the caregiver can better work together for the benefit of the patient. The relationship is often dynamic. Motivations, fears, goals, limitations, medical knowledge, and therapeutic options may change with time, particularly with a chronic disease. Both parties should be adaptable and mutually respectful of each other's importance regarding the health of the patient.
The “good and the bad” aspects of chronic dermatological disease are inherent. Seldom does a dermatology patient face an acute lifethreatening situation with all the emotional and financial aspects that accompany them. Yet, very few dermatologic diseases are curable, and consequently chronic management is necessary. Additionally, symptoms may wax and wane independently of therapeutic intervention, leading to the incorrect assumption that a therapeutic intervention is beneficial and should be continued. Most therapies are purely palliative and have potential side effects as well as contraindications. Allergen specific immunotherapy (ASIT) is the only specific therapy for atopy (Mueller 2014). It can reverse an integral part of the underlying pathogenesis and in some cases effect a virtual cure for canine atopic dermatitis (DeBoer 2014).
Chronic Disease Managementfor Small Animals, First Edition. Edited by W. Dunbar Gram, Rowan J. Milner and Remo Lobetti.
© 2018 John Wiley & Sons, Inc. Published 2018 by John Wiley & Sons, Inc.
Summation of effect and threshold pruritus theory can be used to help explain how various factors contribute to the clinical signs (Tater 2012). In this explanation, the threshold at which clinical signs are noted can be represented by a horizontal line. Under that horizontal line are vertical bars stacked upon each other, like building blocks. Once the stacked bars are taller than the line, the threshold is breached. At this point, clinical signs become evident. In some cases, a single factor may be large enough to reach the threshold and in other cases, several factors may be needed. Some veterinarians may use gestures instead of lines or bars to make this point to clients. In this situation, one hand or forearm represents the threshold and the other hand is far beneath the threshold. With the mention of each potential contributing factor, the lower hand incrementally is raised closer to, and eventually exceeds, the threshold.
In a verbal analogy of this concept, the threshold is the top of a drinking glass and the goal is to avoid having water overflow out of the glass. If a glass is filled to the brim (but not overflowing) with water, a single small pebble placed in the water will lead to the glass being too full and water then spilling out. In order to prevent this spillage, the obvious approach would be to prevent a pebble from falling into the glass. While this approach may seem appropriate for the flea-allergic dog where the flea represents the pebble, the scenario is potentially more much more complex. For instance, if the glass was not entirely filled to the brim it could accommodate one or more pebbles without spilling. This translates into the clinical situation in which a dog with a combination of environmental allergies and mild flea allergy may not be able to tolerate any flea bites during the height of pollen season (cup filled to the brim with water). The same patient potentially could tolerate a flea bite or two during a time of year when the pollen count is low (when the cup is not as full).