Dermatology

Allergy 

Allergy is a hypersensitivity to substances that in themselves are not harmful (allergens), such as pollen grains, house dust mite faeces, dander from other animals or food ingredients.

When the allergens, to which an animal is hypersensitive, enter the body (usually through the skin or gut), the immune system reacts far too strongly. With this "exaggerated" reaction, the immune system tries to render the allergens harmless. The symptoms (e.g., itching or diarrhea) do not come from the allergen itself, but from the immune system's reaction to the allergen.

The three most common allergic skin conditions in dogs and cats are flea allergy, food allergy and atopy. The symptoms of these allergies can be very similar. Several allergies can also co-exist.

Because each allergy needs its own treatment, it is important to find out step by step which allergy(s) the animal has. Only then will it be possible to tackle the symptoms properly.

Besides these three allergies, insect bite hypersensitivity, drug hypersensitivity and contact dermatitis also occur, however much less frequently than the above three allergies.

Itching

"Itching is worse than pain." It may be a cliché, but for the owner of an animal with itching, it is often from the heart. It is depressing to look at your own animal that is constantly scratching, biting and scratching. Moreover, it often costs the animal so much energy that it becomes listless and loses its usual cheerfulness. Many owners therefore feel that their animal is no longer themselves.

Scratching often also causes him to lose hair, or even wounds.

What can you do about it? You can have a "shot against the itch" (corticosteroids) given, then it usually goes well for a while. But the itching comes back again and another shot every time is not an option: far too dangerous because of the side effects.

Many owners continue to struggle like this because they think there is no solution for their animal. Fortunately, the options have greatly expanded in recent years. Most importantly: do not just treat the itch, but find what is causing the itch. This paves the way to a long-term solution with as little medication as possible. Many animals with itching have an allergy. If it can be found out at an early stage what an animal is allergic to, he will benefit throughout his life.

With a flea allergy, the animal can even become itch-free (most of the year). With a food allergy too, if he is given the right food. No medication is needed for this. An allergy to environmental allergens (atopy) always requires treatment, but even here it is possible in most animals to find a treatment that suppresses the itching without too many side effects. Hair loss Every animal suffers from hair loss from time to time, which is nothing to worry about. But when bald patches appear in the coat, something is wrong. Most owners want a quick solution to this, as it is no fun to walk around with a bald animal. But...a quick fix is not always possible.

First, the cause of the baldness must be found, before choosing the right treatment. There can be many different causes for hair loss. Hormonal problems, parasites, fungus, an allergy, etc.

Some animals also have a genetic predisposition to go bald. Figuring out exactly what is going on is often not an easy task. But the good news is: if it is successful, hair growth always comes back completely. Flaking When the skin is stimulated, it often reacts with an increased production of skin cells. Those skin cells come off on the outside at an accelerated rate, and this is visible as scaling. Flaky skin does not form a good skin barrier, which often leads to bacterial infection; a microbial skin infection develops. The skin starts smelling and itching, and the animal starts scratching and further breaking the skin. This creates a vicious cycle.

Allergic animals often have scaly skin, but scaling can also occur in many other skin diseases. Examples include parasites, hormonal disorders or leishmaniasis. To tackle the problem structurally, the vet and/or dermatologist must identify and treat the cause of the skin disease. Meanwhile, flaking can be contained with supportive treatments, including agents that improve the skin barrier and washing with special shampoos.

Stinky fur

It is no fun for an animal to smell, even though it may not bother him so much itself. An animal that smells unpleasant is petted less often and its owner does not dare to take it anywhere anymore.

Thus, a smelly coat leads to reduced well-being of the animal. Of course, the owner's living conditions do not improve either with the constant proximity of an unfavorable-smelling animal.

Washing with a special shampoo can sometimes provide a solution but the improvement is often only temporary. Especially if the smell is accompanied by problems such as hair loss, flaking or itching, it is worth having your vet investigate the background of the problem. Possibly your pet has an allergy or some other skin disease. Only once this problem is addressed will the foul smell really disappear, and you can give your pet a nice cuddle again.

Ear infection

Ear infections are often a painful and persistent problem. Ear infections can be part of a skin disease, such as an allergy. But ear infections can also be an isolated problem, for example when there is a grass ear, polyp or tumor in the ear.

In addition, the deeper parts of the ear may also be affected. Obviously, such different problems also require different treatments. It is not always easy to find the right treatment, but one thing is certain: not treating is not an option.

There is a solution to allergy, but the road to that solution can be long and takes time. We walk, with you, that road step by step.

Do you have any questions following the above information? If so, please contact us.

Atopy

Atopy is not a disease; it is a predisposition to develop an allergic condition. In the dog/cat, this allergic condition usually manifests through the skin, this is called atopic dermatitis.

This skin disease can occur in animals with impaired skin barrier function and a hereditary hypersensitivity to harmless environmental allergens (such as house dust mites, tree and grass pollen and dander from other animal species). The allergens enter the skin more easily due to the disrupted skin barrier and trigger inflammatory skin reactions and itching. As the dog starts scratching, the skin becomes irritated and damaged, exacerbating the inflammation of the skin.

Also, in dogs with atopic dermatitis, the balance between the skin and the bacteria and yeasts normally found on it in small numbers is often disturbed. This can cause this so-called microbial flora to multiply and worsen the inflammation of the skin. This phenomenon is called microbial dermatitis. As a result, the condition of the skin deteriorates even further. In some of the animals with atopic dermatitis, food allergens also seem to be able to worsen the symptoms. Finally, the severity of the complaints is strongly influenced by several other factors, e.g., temperature, humidity, hormonal fluctuations and stress.

Because so many different factors contribute to skin inflammation and itching, symptoms can vary greatly. Every animal has an itch threshold. All factors contribute to itching to some extent. The sum of all those factors determines whether the itching exceeds the itch threshold. The itch threshold is not always the same, e.g., it is often lower at night than during the day. Therefore, atopic animals tend to be itchier at night.

Over time, the various factors that contribute to itching are not always the same. For example, environmental allergens are present only a limited part of the time (in the case of pollen grains), weather conditions change and the dog sometimes goes swimming. As a result, the itch sometimes exceeds the itch threshold, and sometimes not. As a result, atopic animals often have highly variable symptoms. Usually, complaints are worse in summer, even if animals are allergic to allergens that are present all year round, such as house dust mites. This is because in summer many other factors are often present to the maximum extent: heat, humidity and swimming. The skin is the barrier between the outside world and the body.

The skin's main functions include keeping harmful organisms and substances out and keeping moisture in. Normal skin can do this just fine because the skin cells are, as it were glued together, like the bricks and mortar of a wall.

In animals with atopic dermatitis, the skin barrier is disrupted because, among other things, the composition of the fats in the sealant layer is different. As a result, the skin becomes porous, so to speak, with all its consequences. Every animal has a small number of bacteria and yeasts on its skin. These so-called micro-organisms feel good in places where it is warm and moist: in the nose and around the mouth, under the tail and between the toes.

Healthy skin ensures that the number of micro-organisms is contained. Moreover, such healthy skin has a good skin barrier, which prevents bacteria and yeasts from doing harm. In allergic animals, the defense against the microflora of the skin is disturbed. This allows these micro-organisms to multiply and grow to large numbers, this is called microbial overgrowth. Moreover, because their skin barrier does not function properly, the bacteria, yeasts and the toxins they produce (toxins) can easily enter and cause inflammation on site: microbial dermatitis.

In 75% of dogs with atopic dermatitis, the first symptoms become apparent between the first and third year of life. It is rare for symptoms to appear at an age younger than 6 months. Atopic dermatitis is more common in certain breeds than others, for example the German Shepherd, Shar-Pei, Terriers, Shih-Tzu, Labrador retriever, Golden Retriever, Boxer, French Bulldog, English Bulldog and American Bulldog. The main symptom is itching. Furthermore, the allergy itself mainly causes redness and scaling of the skin. The symptoms can get worse by scratching, rubbing, biting and licking, eventually causing bald patches and elephant skin. If microbial dermatitis is also present, small bumps and crusts will form. Sometimes there is also more severe inflammation with swelling of the skin and bloody effusions and pus may be seen.

Skin problems are usually found on the head (especially around the muzzle and eyes), in the armpits, groin, on the belly and on the paws. Very many atopic dogs have ear infection as their main complaint. A small proportion of atopic dogs also have hay fever symptoms such as sneezing and eye discharge.

The complaints may or may not be seasonal, depending on the allergens to which the dog is hypersensitive. Also, the severity of the symptoms varies under the influence of a variety of factors such as temperature and humidity and internal conditions of the dog (stress, hormone fluctuations).

Determining whether a dog has atopic dermatitis is not easy; a complete range of examinations must be carried out before this diagnosis can be made. It is important that this is done very carefully, because the consequences are huge: a dog with atopic dermatitis will need a lifetime of treatment and extra care. For atopic dermatitis to be diagnosed, several conditions must be met: First, the nature of the skin problems must fit this allergy. In addition, the role of infectious causes and other allergies (such as food allergy and flea allergy) must be clear.

Once it has become clear that the dog has atopic dermatitis, further allergy testing can be done. A skin test and blood tests can then try to show which allergens the dog is hypersensitive to. No allergy test provides one hundred per cent clarity. Therefore, it makes sense to compare the results of both allergy tests. A negative result does not necessarily mean that there is no allergy. It only indicates that there are no antibodies against the tested environmental allergens at that time.

A skin test (intradermal test) can only be done on a part of the skin that is not inflamed. First (usually on the chest wall) a piece of fur of about ten by fifteen is shaved away. At this spot, a small amount of allergen solution is injected into the skin in a fixed sequence each time.

Exactly which allergens are tested depends on the allergens the dog encounters. The total number of allergens is usually between 20 and 24. 2 control solutions are always tested along with the test: a positive and a negative control to see if the skin responds well to the test. Once all the allergens have been injected, the test should take effect for about 10 minutes. During this time, the dog should not scratch or bite the test area. If it is cold, he should not go outside.

After this, the test can be read. If there is swelling at the injection site of a particular allergen, the dog is allergic to it. The swelling is always compared with the reactions seen in the positive and negative controls to draw the right conclusion. Finally, the positive reactions and the positive controls are treated with an itch-relieving ointment. Skin test injections are not very painful: by using a small needle and preferably allowing the test fluid to come to room temperature first, most dogs experience the pricks as irritating rather than painful. It is therefore almost never necessary to put a dog under anaesthesia for this test.

The blood shows whether the body has reacted to certain allergens by producing antibodies. For this blood test (serum test), some blood is taken and sent to a specialized laboratory. This laboratory tests a fixed panel of allergens (Northern European panel), which includes mites, pollen grains as well as dander from other animals.

Once it has been established that your pet has atopic dermatitis, the most logical solution would seem to be to prevent him from coming into further contact with the causative allergens. However, this solution is usually not feasible in everyday life.

There are several options for treating a dog with atopic dermatitis:

• Desensitization (=hyposensitization)
• Itching and anti-inflammatory drugs
• Support of the skin barrier
• Antimicrobial treatment

Different forms of treatment are often used side by side: a tailor-made treatment, so to speak, is created for each animal with atopic dermatitis. The key is for you as the owner to learn to discover which stimuli your animal reacts badly to and which medications he responds well to. This is a process that owner and vet and/or dermatologist go through together. On average, it takes a year to find a stable treatment strategy.

Desensitization

This treatment (also known as hyposensitization or allergen-specific immunotherapy = ASIT) involves injections of a desensitizing fluid. This contains extracts of the allergens to which the dog is hypersensitive. These injections are given according to a certain schedule in which the period between injections (the interval) increases and the dosage slowly increases to a certain maximum. It may take some time before the results of this treatment become visible: 6 months on average.

After 8-9 months, the treatment is evaluated. In 60-70% of dogs with atopic dermatitis, it is then found that a clear improvement has been achieved with this treatment. If desensitization is successful, the injections should be continued for life.

Not all dogs become completely symptom-free with this treatment. Therefore, a combination is often made with other forms of treatment, often aimed at supporting the skin barrier and/or controlling microbial inflammation. Especially in the first months of desensitization, when modest improvement can be seen, drugs that inhibit skin itching and inflammation are also often used as a temporary adjunct.

Itching and anti-inflammatory drugs

Corticosteroids work quickly and are cheap, but can have unwanted side effects with prolonged use of higher doses, such as heavy drinking and urination, weight gain, depression and eventually serious illnesses such as diabetes or Cushing's disease. This problem can sometimes be avoided by applying the corticosteroids not in the form of injections or tablets but on the skin itself in the form of an ointment, cream or spray. In atopic animals with ear infections, an ear ointment based on corticosteroids is indispensable.

Ciclosporin works somewhat more slowly than corticosteroids, is relatively expensive, but has fewer side effects: apart from mild gastrointestinal discomfort, few side effects are seen. Ciclosporin should be given for at least 8 weeks; if no improvement is seen after 8 weeks, treatment should be stopped. If the ciclosporins have a positive effect, then a decision can be made to reduce the dosage to every other day and possibly to every two days in the future. Antihistamines (such as cetirizine) only work in a small proportion of atopic animals. If the animal responds well to them, they can be used for longer periods of time without objection.

These drugs are sometimes given as the main treatment for atopy, or temporarily in addition to desensitization. If given as the main treatment, they should be given for life. An attempt can be made, however, to reduce the treatment to a maintenance dose. Like desensitization, this treatment is often combined with treatments aimed at improving the skin barrier. This can often lower the maintenance dose needed to suppress symptoms.

Various agents can be used to support the skin barrier:

• Moisturizing shampoos and lotions
• Feed supplements with omega3/omega6 fatty acids
• Feeds with an increased content of omega3/omega6 fatty acids
• Spot-on with omega3/omega6 fatty acids

Treatment of microbial dermatitis

Microbial dermatitis, i.e., inflammation due to yeasts or bacteria, must always be controlled because it is a major factor in the vicious circle of skin problems an atopic animal can get into. Through microscopic examination of skin material, your vet can determine whether there is a bacterial or yeast infection or a combination of both. A superficial bacterial infection can usually be treated using a mild antibacterial shampoo. If the inflammation is more severe, antibiotics should be used. Here, it is important to give the antibiotics for a sufficiently long time, i.e., at least three weeks. In case of a severe inflammation with a lot of crusting, an antibacterial shampoo can additionally be used. A yeast infection is usually treated with a special shampoo. Only in very severe cases is this not enough and medication in tablet form (ketoconazole) should be given.

Both bacterial and yeast infections of the skin tend to recur repeatedly, especially if the allergy is not yet completely under control. To prevent this, it is advisable to keep washing the animal regularly with a special shampoo against bacteria or yeast. Atopy is well treatable, each animal with atopy needs an appropriate treatment plan.

Do you have any questions following the above information? If so, please contact us.

      Food hypersensitivity in dogs

Food hypersensitivity is a combination term for food allergy and food intolerance.

Food allergy means that your dog is allergic to certain allergens that he absorbs through his food (immunological reaction). In food intolerance, the immune system does not play a role in the reaction to food, but is the absence of a particular enzyme needed to fully digest a specific food.

Food allergens

Any food constitutes a possible allergen, but in practice, the most common allergens are beef, dairy products and wheat. However, chicken, egg, lamb, soy and pork are also common. In exceptional cases, grain and food additives can also be a problem.

In a food allergy, dogs may start showing symptoms after prolonged exposure to a particular brand or type of food, while food intolerance symptoms may appear after just a single exposure to a food ingredient. A food hypersensitivity is characterized by non-seasonal itchy skin and/or skin inflammation, gastrointestinal complaints and can occur at any age and in any breed. The clinical signs can vary; itching, self-induced baldness, scaling of the skin, dermatitis, ear infection, inflammation of the soles of the feet, vomiting, diarrhea occur. We can diagnose food intolerance using an elimination diet.

However, before we can start an elimination diet, it is important that bacterial skin infections and parasites in your dog are cleared. An elimination diet consists of a protein source and carbohydrate source unknown to your dog. With an elimination diet, nothing else should be given for at least 6 weeks other than the prescribed elimination diet. So also no biscuits, sweets, bread and the like.

Keep your dog on a leash during the elimination diet so you can prevent him/her from eating things from the street. Also keep in mind when giving any medication, this should NOT be given with butter, cheese or a piece of meat. Medication in this case should be given together with a soft version of the elimination diet.

As for the elimination diet, there are several options:

1. Self-prepared elimination diet:
10-15gr/kg/day of a carbohydrate source such as:
white rice or potato.
10-15gr/kg/day of a, for your dog,
foreign protein source such as: ostrich, goat, venison, horse or rabbit.
You cook the protein source together with the carbohydrate source, if necessary you can cook a week ahead and freeze the meals.

2. As it can be difficult to find certain 'strange' protein sources, Hill's Canine has developed z/d.
This is an already pre-packed and cooked protein source such as: rabbit, venison, horse and quail. In addition, you should give 10-15gr/kg/day of a cooked carbohydrate source such as: white rice or potato.

3. Ready-to-eat diet (Hill's Canine z/d):
This is a diet (kibble and/or canned) based on hydrolyzed proteins. In this, the molecular weight is greatly reduced, so the body no longer recognizes it as protein. Make sure that during the elimination diet period you choose from a single protein source and a single carbohydrate source, as should your pet's symptoms not disappear, we can switch to another combination. Unfortunately, ready-made diets do not offer a 100% guarantee, some animals are so sensitive to proteins that they still react to hydrolyzed proteins themselves. In these cases, an elimination diet will still have to be prepared yourself. Should your dog not react well to both the ready-made diet and various combinations of the self-prepared elimination diet, there is still the option of switching to a diet containing only vegetable proteins. When your dog has responded positively to the elimination diet, it is time to start provoking.

Officially, this involves giving foods that the animal has been offered before, and this is done per food for several days. After giving your dog a familiar food, you should keep a close eye on whether any symptoms return. This way, we can discover which allergens are responsible for complaints in your dog. Should any complaints arise following such a provocation, it is advisable to return to the elimination diet, and as soon as your dog is again free of complaints, you can perform another provocation with another food. In some cases, this way (looking for food that is NOT suitable for your dog) of provoking is not desirable and we can also do it in another way. We always start by performing provocations on the complete food first, for this you can use ready-made food with a single protein source (Hill's D/D) In this way we will provoke with, generally, strange protein sources and thus look for which complete food is WELL suitable for your dog with food hypersensitivity.

After you have found a complete food for your dog, you can start offering your dog snacks again in the way described earlier above, following snack by snack for several days in a row. In this way, you will create a food notebook for your dog that lists what your dog can or cannot eat due to his/her food hypersensitivity.

Click here for the video information: Elimination diet

Click here for the video information: Maintenance diet

Do you have any questions following the above information? If so, please contact us.

Food hypersensitivity in cats

Food hypersensitivity is a combination term for food allergy and food intolerance.

Food allergy means that your dog is allergic to certain allergens that he absorbs through his food (immunological reaction). In food intolerance, the immune system does not play a role in the reaction to food, but the lack of a particular enzyme needed to fully digest a specific food is the

Food allergens

Any food constitutes a possible allergen, but in practice, the most common allergens are beef, dairy products and fish. However, lamb, chicken and poultry also occur. In exceptional cases, food additives can also be a problem. With a food allergy, cats may start showing symptoms after prolonged exposure to a particular brand or type of food, while food intolerance symptoms may appear after just a single exposure to a food ingredient.

A food hypersensitivity is characterized by non-seasonal itchy skin and/or skin inflammation or gastrointestinal complaints and can occur at any age and in any breed. Clinical signs can vary; itching, self-induced baldness, scaling of the skin, dermatitis, ear inflammation, inflammation of the soles of the feet, vomiting and diarrhea occur.

We can diagnose food hypersensitivity using an elimination diet. However, before we can start an elimination diet, it is important that bacterial skin infections and parasites in your cat are cleared. An elimination diet consists of a protein source and carbohydrate source unknown to your cat. With an elimination diet, nothing else should be given for at least 6 weeks other than the prescribed elimination diet. So also no biscuits, sweets, bread and the like. Keep your cat indoors during the elimination diet so that you can prevent him/her from eating things from the street or neighbors.

Also keep in mind when giving any medication, this should NOT be given with butter, cheese or a piece of meat. Medication in this case should be given together with a gentle variant of the elimination diet. As for the elimination diet, there are several options:

1. Self-prepared elimination diet: 10-15gr/kg/day of a carbohydrate source such as: white rice or potato. 10-15gr/kg/day of a, for your cat, strange protein source such as: ostrich, goat, venison, horse or rabbit.

You cook the protein source together with the carbohydrate source until done, if necessary, you can cook a week ahead and freeze the meals.

2. As it can be difficult to find certain 'strange' protein sources, several special diet foods have been developed. These are an already pre-packed and cooked protein source such as: rabbit, venison, horse and quail. In addition, you should give 10-15gr/kg/day of a cooked carbohydrate source such as: white rice or potato.

3. Ready-to-eat diet (Hill's Feline z/d): This is a diet (kibble and/or canned) based on hydrolyzed proteins. In this, the molecular weight is greatly reduced, so the body no longer recognizes it as protein. Make sure that during the self-prepared elimination diet period you choose from a single protein source and a single carbohydrate source, as should your pet's symptoms not disappear, we can switch to another combination.

Unfortunately, the ready-made diets do not offer a 100% guarantee, some animals are so sensitive to proteins that they even react to hydrolyzed proteins. In these cases, an elimination diet will still have to be prepared yourself.

When your cat has responded positively to the elimination diet, it is time to start provoking. Officially, this means giving foods that the animal has been offered before, for several days per food. After giving your cat a familiar food, you should keep a close eye on whether any symptoms return. This way, we can discover which allergens are responsible for complaints in your cat.

If any complaints arise following such a provocation, it is advisable to return to the elimination diet. As soon as your cat is again free of complaints, you can carry out another provocation with another food. In some cases, this way (looking for food that is NOT suitable for your cat) of provoking is not desirable and we can also do it in another way. We always start by performing provocations on the complete food first, for this you can use ready-made food with a single protein source (Hill's D/D) In this way, we will provoke with generally strange protein sources and thus look for which complete food is WELL suitable for your cat with food hypersensitivity.

After you have found a complete food for your cat, you can start offering your cat snacks again in the way described earlier above, following snack by snack for several days in a row. This way, you will create a food notebook for your cat that lists what your cat can or cannot eat due to his/her food hypersensitivity.

Do you have any questions following the above information? If so, please contact us.