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Managing the Small Animal Dermatology Patient
Kim Horne
Introduction
The skin is the largest organ of the body and performs many vital functions. It acts as a barrier; offers protection against environmental elements and the development of infections and cutaneous neoplasms; produces vitamin D and keratinized structures such as the hair and claws; regulates temperature; acts as storage for materials such as electrolytes and vitamins; is a primary sense organ; and is an important indicator of general health as well as internal disease (Miller et al. 2013). Skin and ear diseases are very common in our small animal patients. Recent statistics show that pet insurance policyholders' top four medical conditions were related to ear and skin problems (Nationwide 2018). While these may not be the primary reason the patient is presented to the veterinary hospital, clients will often ask to have their pet's skin or ears checked during the visit; or you may discover something during the physical exam that the client was not aware of. Unfortunately, many different dermatological diseases present with similar clinical signs and many of these conditions are only controllable and not curable. Dealing with these cases can be time consuming and frustrating for the pet owner as well as the veterinary staff. The good news is that veterinary technicians and veterinary nurses can play an important role in all aspects of the management of these cases. From taking a complete history, performing diagnostic procedures correctly, to providing thorough client education and following up with the patients' progress - these are the essential elements for achieving success with these cases. The technician's involvement with phone call updates and ensuring recheck appointments are scheduled can improve client compliance and lead to improved patient management.
History
A dermatology history questionnaire can be an efficient way to collect important information. Many dermatology books contain examples of these which can be modified to fit the needs of each practice (Bergvall 2012; Miller et al. 2013). See Figure 1.1 for an example. Filling out the questionnaire will get the client thinking about their pet's dermatology problems, and should be completed prior to the exam. Ideally the questionnaire can be sent to the client in advance of the appointment or the client can arrive early in order to complete the questionnaire. The questionnaire can be very helpful not only for the initial appointment, but also to refer back to if and when the pet's problem recurs or symptoms change.
Figure 1.1 Dermatology patient history questionnaire.
Source: Reprinted by permission of the Veterinary Medical Center, University of Minnesota.
When taking the history, the breed, age, and sex of the patient can give clues as to which diseases may be more likely to affect them. Examples of important questions to ask the owner of a pet with dermatological signs include: Is the pet itchy? When did they first notice the problem? How has it changed over time? If they have been seen elsewhere for the skin problem, what diagnostic tests have been performed? What medications and treatments have been tried? What has worked for the patient and what hasn't? Is the pet taking any current medications (including over-the-counter products)? Did the medication help to improve the skin lesions and/or reduce the pet's itching? What is the pet's dietary history (including treats)? Is this a seasonal or non-seasonal problem? Are there other pets in the household and if so, are they showing similar signs? Are any humans in the household affected? Good communication and listening skills are essential to obtaining an accurate history.
It is helpful to start at the beginning and get a chronological sequence of events. This can be challenging, as the client may not think that the past information is relevant and may only want to discuss the current issues. Patience and persistence are often required in order to obtain the complete history. And sometimes it is necessary to ask the questions differently in order to get accurate information. For example, you may notice that the dog has alopecia and saliva staining on the paws. You assume the dog has been licking or chewing at his feet. You ask the owner if the dog is itchy (knowing that pruritus can be exhibited by scratching, licking, chewing, or rubbing behavior). The client may only think of scratching as a sign of itching, and will answer "no" to your question. You may then need to ask the client specific questions such as: Have you observed your dog licking, chewing, rubbing, or scratching? If the answer is yes, follow-up questions to ask include: What areas of the body, how often does this occur, and how intense is the licking, chewing, rubbing, and scratching? Each response should be documented in the medical record. You can also ask the client to rate their pet's level of pruritus on a numerical scale of 0-10 (with 0 being none to 10 being constant itching). Providing clients with a visual analog scale (VAS) that includes behavioral descriptions of pruritus can help standardize owner responses (Bergvall 2012, http://www.cliniciansbrief.com/sitesDefault/files/CaninepruritusScale.pdf). The VAS may be more sensitive (Miller et al. 2013) than the numerical scale. This pruritus score can be used to compare the patient's progress at follow-up visits. Pruritus is often the presenting complaint, especially if the pet sleeps in the owner's bedroom and is keeping them awake at night.
Collecting a thorough history can be time consuming, and the veterinary hospital may want to allow additional time for these appointments. Ideally, the person with the most knowledge about the patient should be the person present for the exam. This should be explained to the client when they are scheduling the appointment. A comprehensive history can help the veterinarian develop the most efficient and cost-effective diagnostic and treatment plan for the patient.
Dermatological Procedures
In order to make a diagnosis, the patient history, physical examination findings (see Figure 1.2), and diagnostic tests are used. It is often the veterinary technician's job to perform the diagnostic testing and it is important that the procedure be performed correctly. Keep in mind that a negative test result does not always rule out a disease. The following procedures are often performed on the dermatology patient.
Figure 1.2 Dermatology physical exam form.
Source: Reprinted by permission of the Veterinary Medical Center, University of Minnesota.
Flea Combing
This technique is used to look for fleas and/or flea dirt (flea feces) if fleas are not found visually on physical exam.
Procedure (Figures 1.3-1.6):
- Using an ultra-fine flea comb, comb the pet's hair coat thoroughly. You may get lucky and find the adult flea! If not:
- Place the collected debris on white paper.
- Wet the debris with water and look for a reddish tinge that indicates dried blood. If positive, this reddish tinge could be from either flea feces or a crust. The next step is to examine the debris microscopically to determine if the debris is flea feces (flea feces are comma shaped).
Figure 1.3 Flea combs.
Figure 1.4 Cat with alopecia along dorsal lumbosacral area.
Figure 1.5 Flea excrement, often referred to as "flea dirt."
Figure 1.6 Microscopic view of flea feces.
Ear Cytology/Swab
This procedure is used to identify yeast and bacteria. Always swab both ears even if only one ear appears to be affected. Bacterial organisms can be identified morphologically as cocci or rods. Malassezia pachydermatis is the most common fungal organism present in ears. The budding yeast usually appears as a peanut or footprint shaped form. Make sure you examine cytology before adding any products into the ears in case a bacterial culture and susceptibility test is indicated.
Procedure when looking for bacteria and yeast (Figures 1.7-1.13):
- Gently pull up on the ear pinna (see Chapter 4 for an ear diagram) to straighten out the ear canal and insert a cotton-tipped applicator swab into the bottom of vertical ear canal and rotate.
- Roll the swab onto a labeled microscope slide and heat fix if this is standard for your practice.
- Stain with Diff-Quik® or new methylene blue.
- Examine microscopically under an oil immersion lens, 100×. Be sure the microscope is set so the light is up, the condenser is up and open, and the contrast is low. This will allow for the best viewing of yeast and bacteria. These settings should be employed anytime your subjects are cells or infectious agents. (Note: If you are not finding much on the slide, look for epithelial cells with evidence of bacteria and yeast.)
Figure 1.7 Gently pulling up on...
