Dog allergy and atopic dermatitis: how to recognize and treat them?
Allergy? Atopy? There is so much talk about atopy and allergy in animals, but do you know what these terms really mean??
What are these mysterious diseases and what causes them?
In this article, you will learn how to recognize allergy and atopic dermatitis in a dog, and how they differ.
I will also explain to you how to treat them and what home remedies you can use on your own.
Now check if your dog is at risk and if allergies can be prevented.
- What is atopy?
- What is an allergy?
- Dog allergy
- Flea allergic dermatitis in FAD
- Food allergy in a dog
- Contact allergy in a dog
- From what the allergy arises?
- Dog allergy diagnosis
- Dog allergy symptoms
- Dog atopic dermatitis
- The mechanism of the development of the disease
- Atopic Dermatitis: Diagnosis
- When can we suspect atopic dermatitis?
- Racial predilection for AD
- Assessment of the severity of itching
- Intradermal tests
- Treatment of allergies in dogs
- How long does an allergy last in a dog?
- How much does it cost to treat a dog's allergy / atopy?
- Home remedies for dog allergies / atopy
What is atopy?
Atopy is a genetically determined disorder of the immune system, as evidenced by the presence of diseases with this background in animals in the same line / breeding.Genetic predisposition plays a major role in atopy, but its appearance and course are significantly influenced by environmental factors.
What is an allergy?
Allergy it's a much broader concept. It is a complicated response of the immune system to contact with an irritant with a protein structure called allergen.
This response is based on the production of specific protein substances (mainly antibodies of the class IgE) and stimulation T lymphocytes.
During the next contact with the allergen after the first contact, this in turn leads to the development of an inflammatory reaction.
Inflammation is the result of the release of chemicals responsible for the onset of allergy symptoms during an allergic reaction. These include, for example:
- cytokines and others.
An allergic reaction can vary in severity, from coughing and itching to respiratory failure, heart failure, and even death.
We observe inflammation within one organ (e.g. eye, nose) or the entire organ system (e.g. respiratory system in the course of bronchial asthma).Allergy may appear only seasonally, i.e. during the period of dusting of the sensitizing plant, or throughout the year - e.g. as a result of exposure to dust mites constantly present in the dust.
An allergic reaction may also occur immediately after contact with the sensitizing agent, or with a delay in relation to the exposure to the allergen, mainly with the activation of IgE antibodies, but also without their participation in the course of the reaction.
In the veterinary office, the basis for recognizing whether we are dealing with allergy or z atopy there is a thorough interview.
It is also worth doing additional tests, including:
- blood test,
- intradermal tests,
- elimination and provocative diets.
Among my patients, I most often meet:
Flea allergic dermatitis in FADDog's allergy to fleas
Flea allergic dermatitis - APZS - is the body's response to the protein found in flea saliva.
Even contact with 1 flea.
Allergy in a dog to fleas (APZS) is seasonal in nature, in our climate it occurs mainly in the warm months.
Flea saliva contains several allergenic components with a protein structure and an allergic reaction is activated after a parasite bite.
Food allergy in a dogFood allergy in a dog
Food alergy - its characteristic image is occurrence itching.
Gastrointestinal problems are rare and can take the form of acute allergic gastritis, eosinophilic enteritis or allergic colitis.
It is known that just like in humans, food allergy in a dog results from hypersensitivity of the anaphylactic type to food allergens, but the participation of type three hypersensitivity and delayed hypersensitivity is also possible.
Based on the clinical picture, it is impossible to distinguish food allergy from food intolerance resulting from the presence of histamine in the food or due to the fact that food components lead to the release of histamine and other mediators of early hypersensitivity from mast cells by a non-immunological route.Once mediators have been produced in a susceptible animal, sensitivity persists long after elimination of the allergenic protein / agent.
This explains why clinical improvement in dogs with food allergies is sometimes not achieved until after several weeks follow a hypoallergenic diet.
The suspicion of a food allergy in dogs is usually made on the basis of a very thorough interview, no response to steroids and elimination diet.
Contact allergy in a dogDog contact allergy
Contact allergy otherwise contact dermatitis is the result of direct skin contact with environmental substances.
It may be irritating or allergic.
In many cases, it is very difficult, and sometimes even impossible, to determine what type of contact dermatitis is.
Allergic contact dermatitis, unlike irritating dermatitis, has an immunological background.
Type IV hypersensitivity (cellular, i.e. late) is responsible for its development.Unlike irritant dermatitis, a reaction develops in response to substances non-irritating.
Prior to induction of clinical symptoms (full-blown phase), a time-consuming phase of exposure to the allergen is required. This period may last from 6 months to even two years.
As you can see, there are many types of allergies. Later in this article you will learn which substances / products are known to have a greater tendency to induce an immune response in the body.
From what the allergy arises?
As you know, there is an allergic reaction response to the protein contained in the allergen.
Therefore, potentially any substance with a protein component has the right to cause an allergic response.
The best known allergens that cause contact allergies are:
- tobramycin and bacitracin,
- benzoyl peroxide,
- tea tree oil,
- peruvian balm,
- dahlia (Compositae),
- primula (Primulaceae),
- pine and other conifers,
- triple serpentine,
- chrome (cement, leather collars),
- nickel (metal collars).
- The remaining:
- rubber (vulcanization accelerators),
- artificial fabrics,
- Food products: virtually any type of meat or protein, whether of animal or vegetable origin.
Dog allergy diagnosisSuspicion of an allergy in the dog
Imagine you have a dog that experiences frequent scratching, recurrent skin lesions, and body skin biting.
How to proceed then?
On this basis, can you suspect that your pet is allergic??
When an animal whose owner suspects allergies enters the office, I start the conversation with a very thorough interview intelligence.
Sometimes it even includes a thorough analysis of the last 6 months of a dog's life, including:
- applied prophylaxis,
- supplements used,
- the anti-parasitic agents used.
After analyzing this period, we begin testing the animal with collecting material from the lesions - scrapings, prints and sometimes fine needle aspiration biopsies.
Dog allergy symptomsDog allergy symptoms
Typical changes in the presence of allergies are:
- purulent papules or pimples,
- secondary crosshair injuries,
Usually observed severe itching - or manifested by scratching or chewing a part of the body.
In connection with the damage to the superficial layer of the skin, we often observe it as well pyoderma, which further aggravates the itching in the animal.Sneezing is rarely seen as a symptom of allergy in animals.
We also sometimes observe allergic conjunctivitis, but it is rare.
In the video below you can see what a dog's food allergy and rash looks likehttpv: // www.youtube.com / embed / Rv-LWdfKPh4
Dog atopic dermatitis
Let's talk a moment about atopy - what are the symptoms, diagnosis and treatment options in the dog?
The symptoms of the disease result from the production of IgE antibodies against environmental allergens.
The most common causes of reactions in dogs are:
- mite allergens house dust,
- allergens mold,
- allergens plant pollen.
The mechanism of the development of the disease
Formation of the entire cascade of reactions atopic dermatitis it is complicated and not fully understood…
Preliminary studies suggest that the allergen penetrating the epidermis is taken up by IgE antibodies bound to the cell membrane Langerhans cells.
These cells penetrate the dermis and act as antigen presenting cells T lymphocytes, initiate an immune response.
IgE antibodies, by binding to the receptors for the Fc fragment of IgE on the surface of mast cells and basophils, lead to their so-called. coats.
The subsequent penetration of the allergen and its binding to specific IgE antibodies enveloping mast cells leads to their activation, which is reflected in the release of the granularity of chemical mediators of inflammation from their cells.
These mediators contribute to the induction dermatitis and itching.
Atopic Dermatitis: diagnostics
Unfortunately, we do not have specific laboratory tests that would be able to clearly confirm or exclude atopic dermatitis in dogs.
Atopy also does not have such characteristic clinical symptoms that would allow a clear diagnosis.
Also, the mere statement of a positive response to the applied treatment does not provide grounds for a diagnosis of the disease.
Taken together, the diagnosis of canine atopic dermatitis is not easy.
We base the diagnosis on the basis of an interview, observing clinical symptoms in the examined subject and performing additional tests aimed at excluding other skin diseases with similar symptoms.
Certain clinical diagnostic criteria are helpful in the diagnosis, but the finding of an animal diagnostic criteria should always be interpreted only as a suspicion of atopic dermatitis and not as certain evidence of it.
Before a diagnosis of atopy is made, other pruritic conditions should be ruled out, such as:
- flea allergy dermatitis,
- food allergy and food intolerance,
- scabies and other parasitic diseases,
- bacterial folliculitis,
- contact dermatitis.
We are faced with the situation that similar symptoms may occur in the case of cutaneous mycoses, demodicosis and psychogenic dermatoses.
It should be remembered that in animals with atopic dermatitis it may coexist food alergy or flea allergy dermatitis.
Complications in the form are also common bacterial folliculitis and yeast infection.
When can we suspect atopic dermatitis?When can we suspect atopic dermatitis?
In veterinary dermatology, we use the so-called diagnostic criteria.
Criteria according to Willemse
- Major main criteria:
- the occurrence of itching,
- localization of changes on the face and / or peripheral parts of the limbs,
- lichenization of the flexor surface of the tarsus or extensor of the wrists,
- chronic or recurrent dermatitis,
- having experienced similar symptoms in the past,
- racial or family predisposition.
- Minor secondary criteria:
- the appearance of symptoms before the age of 3,
- erythema on the skin of the face and cheilitis,
- bacterial conjunctivitis,
- superficial purulent staphylococcal dermatitis,
- excessive sweating,
- positive result of the intradermal test - an increase in the level of allergen-specific IgE or IgG antibodies.
Criteria according to Prelaud
- Itching that resolves after treatment with glucocorticoids.
- Erythema of the auricles.
- Bilateral erythematous dermatitis of the fingers and between the toes.
- Inflammation of the lips.
- The appearance of the first symptoms between 6 months and 3 years of age.
Racial predilection for ADWhat breeds are most at risk?
The breeds predisposed to atopic dermatitis include:
- cocker spaniel,
- Boston Terrier,
- bull terrier,
- bichon frize,
- cairn terrier,
- shar pei,
- English bulldog,
- english setter,
- springer spaniel,
- German Shepherd,
- golden retriever,
- Irish setter,
- labrador retriever,
- lhasa apso,
- miniature schnauzer,
- Scottish Terrier,
- sealyham terrier,
- Tibetan terrier,
- wirehaired fox terrier,
- west highland white terrier,
- yorkshire terrier.
Dog breeds suspected of having a predisposition to atopic dermatitis:
- american cocker spaniel,
- short-haired German pointer,
Assessment of the severity of itchingDog atopic dermatitis - symptoms
It is helpful in determining whether we are dealing with atopy / allergy assessment of the severity of itching.
It is a subjective assessment of the owner on a scale - itching is scored in points from 1 to 10.
Value 0 means that the animal has not scratched, chewed or licked its skin within 24 hours.
Value 10 means that the dog's scratching, biting and licking is continuous.
The owner of the animal, observing it, marks the intensity of the itch on the scale.
To facilitate the visualization of the itching, the owner marks the dog itching that he or she has observed on a scale from a length of 200 mm, graduated by 5 mm.
Another method used to assess the severity of itch is an index based on a 10-point itch severity scale (from 0 to 10) assessed on 6 areas of the body:
- The facial part of the head.
- The circumferential stretches of the limbs.
- Armpit and groin.
- Sides of the chest.
- On the back (lumbosacral region).
- Outer ear canal.
In addition, they prove to be helpful in the diagnosis of allergies intradermal tests.
These tests involve the intradermal injection of small amounts of an allergen extract.
If we are dealing with hypersensitivity to a given substance, then after 15-30 minutes this causes redness at the site of the intradermal application of the solution.
We consider the positive result of the intradermal test when we confirm the presence of specific antibodies, but not always in this case the animal has to be atopic.
Therefore, any positive reaction must be assessed in conjunction with information from the interview, e.g. the time between symptoms and positive allergens.However, a negative result of the intradermal test does not necessarily rule out atopy.
Before performing the test, you should adhere to the drug discontinuation periods.
For steroids long acting is recommended 3-month the period before the test, for oral prednisolone - 6 weeks, and 1-2 weeks - for topical steroid preparations.
Treatment of allergies in dogsTreatment of allergies in dogs
It is an ideal type of therapy in the case of allergic diseases…
avoiding the allergen.
However, very often it is impossible to change the conditions of keeping animals due to the cost or time required for it.
As one solution, it is proposed symptomatic treatment, consisting mainly in the administration of steroids with the possible addition of palliative agents.
Since the treatment of autoimmune diseases, which include allergy / atopy, requires longer periods, it is recommended to choose short-acting glucocorticoids, such as:
Medicines are selected individually by a veterinarian and after reviewing each case and the history of the disease.
For cases with allergic skin conditions, an alternative method of effective treatment may be the use of specific immunotherapy, often called desensitization.
It consists in gradually accustoming the body to increasing doses of the allergen in order to reduce the allergic reaction.
Specific immunotherapy changes the body's own mechanisms that lead to allergic diseases.
In human medicine, the advantage of desensitization is the avoidance of new sensitization.
The recommended duration of specific immunotherapy in humans is from 3 months to 5 years. However, in veterinary medicine, where the patient responds well to desensitization, it is recommended lifetime continuation of therapy.
Experience shows that after discontinuation of therapy, most often after 1-2 years, recurrence of the disease should be taken into account.
The effectiveness of the treatment plays a decisive role for both the veterinarian and the patient.
A positive effect is also shown by auxiliary activities, such as. reduction of the allergen in the animal's environment.
The relationship between the patient's age and the effectiveness of treatment is also quite important.
In animals under 1 year of age it only states low effectiveness of desensitization.Dogs that are most likely to succeed in desensitization are allergic to few allergens - up to 8 allergens.
Subsequently, the effectiveness of the therapy depends on the duration of the therapy, strict adherence to the treatment plan, as well as individual patient care.
How long does an allergy last in a dog?
Because of that allergy is an incurable disease, effective specific immunotherapy should be continued years, and even as I already mentioned, throughout the pooch's life.
How much does it cost to treat a dog's allergy / atopy?
Unfortunately - the costs are not low…
Starting with specialized food - in the case of a dog about 20-25 kg - a bag of food is approx PLN 230-300 per month.
For this drugs, approx PLN 100-150 per month.
Visits to a specialist office and periodic examinations - every 3-6 months from PLN 150-400.
Grooming preparations, including dog shampoos and supplements for the dog - from 60-150 PLN per month.
Home remedies for dog allergies / atopyHomemade ways
First, we try to be as effective as possible avoid allergens - house dust mites through regular vacuuming and washing of lairs.
In case of APZS remember to use antiparasitic preparations regularly.
Of course, we also have in mind when it comes to avoiding allergens following a proper diet without the presence of proteins that are suspected to contribute to the allergy symptoms.
A single control, non-allergenic protein diet should be followed minimum 6-8 weeks.
At the moment, more and more offices offer dietary advice and have the ability to compose a so-called diet. homemade, based on ingredients that most owners have in their refrigerator.
As animals belonging to the group of allergy sufferers have a weaker skin barrier, it is advisable to use particularly unsaturated fatty acids Omega-3 and Omega-6.With irritated and red skin - if there is no possibility of visiting a veterinarian, it is recommended use of starch compresses for 15-30 minutes or oat extract 10-15 minutes and rinse thoroughly without drying.
Hopefully, after reading this article, you already know how to spot your dog's first signs of allergy / atopy.
You want to learn more about these conditions and the diet recommended for them? Now add a comment under the article, I will write back as soon as possible.
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