Dermatitis in cats caused by the fungus Malassezia. Causes and Treatments for Malassezia in Dogs

M. pachydermatis - Malassezia fungus, yeast fungus. It reproduces by monopolar budding, which can be detected from the skin and mucous membranes. healthy dogs.

In some cases, the proliferation of M. pachydermatis is associated with the development of dermatitis or otitis externa. The factors that contribute to the pathological reproduction of a fungal infection are not fully understood, but a predisposition to it of some breeds of dogs has been identified and diseases associated with Malassezia have been diagnosed.

Symptoms

The disease is accompanied by the presence of erythema, itching, peeling of the skin, oily seborrhea, and especially bad smell, which occurs when the fungus multiplies in the folds of the neck, interdigital spaces and axillary cavities.

To assess the number of fungi, cytological methods of research are used (identification of bands on an adhesive plaster). The diagnosis of Malassezia is confirmed clinically and by mycological reactions to antifungal treatment.

Some variability has been noted in the flora of Malassezia in different host biospecies, as M. pachydermatis is widely distributed among carnivores. Lipid-dependent species (M. sympodialis) are found in cats. It has been noted that only the M. pachydermatis species is found in dogs, and almost never by others; it is a habitual inhabitant of the skin of healthy dogs. Favorite places of localization (in descending order) are the area of ​​the lips, interdigital folds, mucous membranes, external auditory canal. There are breeds that are most susceptible to "Malassezia dermatitis", with Basset Hounds having much higher skin fungal populations than healthy dogs of other breeds, reflecting the breed's susceptibility to Malassezia. Dogs with atonic disease most often have abnormally high populations of the fungus.

Malassezia fungi most commonly develop in association with S. inlermedius, a companion bacterium that is often seen in Bassets and other breeds that are most affected by Malassesia. Presumably that pathogenic microflora makes a significant contribution to the pathogenesis of the disease itself, and the term "malassezia dermatitis" does not always accurately fit the disease, as it does not take into account important role bacteria. The factors that favor the proliferation of Malassezia on the skin of dogs during the transition from non-pathogenic to clearly pathogenic are not always understood. Presumably in these cases there is a disorder of chemical, physical and immunological defense mechanisms in animals that are normally designed to limit the effect of microbial colonization of Malassezia on the skin.

Malassezia in dogs is found in Bassets, Cocker Spaniels, Dachshunds, Scottish White Terriers, Mini Poodles and Australian Silky Terriers. There was no dependence on the age and sex of the animal; skin disease can successfully develop both in young and in the elderly.

Malassezia in cats. The fungus is most often localized in the ear canals, vagina, rectum and anal sinuses. The probability of infection is high in all felines, regardless of breed and age. Pathological reproduction of the fungus begins with any hereditary or infectious disease that leads to a weakening of the immune system and promotes reproduction. yeast fungus. All primary diseases in cats such as − bacterial infections, seborrhea, allergies various etiologies lead to irritation of the skin, make them susceptible to Malassezia, but it should be noted that cats are the least susceptible of the animals to the disease.

Symptoms of the disease in cats are manifested in the appearance of alopecia, acne on the chin, redness of the skin and seborrhea.

Malassezia treatment. The main therapeutic goal in the treatment of malassezia is to reduce the concentration of the fungus on the skin, as well as associated bacteria, the main disease that favors the development of malassezia. If the fungus is localized only in the surface layer of the skin, then this circumstance makes the animal's body sensitive to local therapy. It is also necessary to get rid of bad smell and exudations. With malassezia in dogs, the treatment was very effective with the use of shampoos containing miconazole 2%, chlorhexidine 2% - this allows you to degrease the surface of the skin, and additionally conduct antibacterial and antifungal therapy. In cats, similar therapy is used, as well as creams and ointments containing azoles. Therapy usually lasts at least two weeks, but it should be continued for 3-5 weeks to prevent recurrence of relapses. Also apply antifungal drugs orally, but only under the strict supervision of a veterinarian.

Frequently Asked Doctor Questions.

The cat began to lose hair, but the test for lichen gave a negative result, what should I do?

If the cat's hair falls out, but on traditional methods she does not respond to research and treatment, it is necessary to check the skin at the site of alopecia for the presence of the fungus Malassezia. It often "disguises" itself as lichen, allergies and beriberi.

Does Malassezia necessarily occur during the life of an animal?

Absolutely not necessary. Usually, the fungus begins to develop in case of violation of the maintenance, feeding of the animal, as well as in the event of serious illnesses inside the body.

How many varieties of Malassezia exist and are they all dangerous to animals and humans?

In total, about ten varieties of Malassezia have been identified: but only Malassezia pachydermatis appears in animals. Varieties are more dangerous for humans: Malassezia furfur and Malassezia globosa.

Veterinary center "DobroVet"

Fungal diseases are a real scourge in both medical and veterinary practice. Often they are difficult to identify, and there are many problems with treatment. One of the classic pathologies (even if rare) is malassezia in cats. In this article, we will tell you in detail about this disease, its manifestations and methods of treatment.

Malassezia pachydermatis is a type of yeast. In the vast majority of cases, they are among the normal microflora of the skin and can be found in any animal. But sometimes something happens, after which the harmless yeast is sharply activated and causes a lot of problems. Usually these fungi are found in the external auditory canal, they are found in the anal sinuses, vagina and rectum. Malassezia can affect animals of all breeds and ages, gender differences also do not play any role.

Why can this microflora be activated? In general, the reasons for this case similar in all fungal infections. Any chronic and especially hereditary autoimmune diseases leading to a long-term decline immune status are classic predisposing factors. Cats suffering from any, or seborrhea, almost always have inflamed and irritated skin. Perhaps the best "bridgehead" for mushrooms can not be found.

Read also: The cat's skin is flaky: a table of symptoms and treatments

Symptoms and diagnosis

The most common symptom of Malassezia in cats is severe baldness. Acne on the chin, sudden seborrhea, and reddened, inflamed skin (pictured) can also indicate an infection. How to find out exactly what is happening, because this symptomatology characteristic of dozens of other diseases, often with fungi not related at all?

The best way to accurately identify this type of pathogen is microscopy, conducted an experienced specialist. To obtain a sample, the method of scraping, washing is used, in some cases a piece of the affected tissue can simply be cut off from the ear of a sick animal. If microscopy reveals great amount yeast, the diagnosis can be considered confirmed. An even more accurate technique is the cultivation of the pathogen on a special nutrient medium. So the symptoms of malassezia in cats are a loose concept, you should not focus only on them when making a diagnosis.

Important! It should be borne in mind that Malassezia may be present on the skin of a healthy animal in any case. So there is always some doubt about the involvement of yeast in the appearance of symptoms. Therefore, the diagnosis is usually confirmed by the cat's response to treatment.

Therapy

Malassezia in cats can be treated in several ways. But once again we warn you that before starting therapy it is very important not only to identify the pathogen, but also to make sure that it was he who caused the disease. If treatment for a long time does not give at all positive effect, should be carried out full examination animal in order to identify the true root cause of the pathology.

Read also: Cat has constipation: why and how to treat?

To create an unsuitable environment for the life of the fungus, it is necessary to remove from the cat's skin excess amount fats. For this, both specially designed shampoos and more familiar products can be used. A 1% solution of chlorhexidine has proven itself well. AT severe cases concentration can be increased. Products containing benzoyl peroxide and sulfur are also used.

These substances not only create an unfavorable environment for fungi, but also degrease the skin, which is especially useful in secondary seborrhea. It should be remembered that when caring for an animal, it is useful to use products containing ketoconazole for personal hygiene. Of course, malassezia has not been identified in humans, but a pathogenic fungus very often causes severe allergies, also known as "cosmetic lichen". In addition, these fungi can interfere natural reaction pH of human skin, which can also lead to various unpleasant consequences.

For the treatment of localized cases of illness antifungal ointments use at least twice a day for several weeks. If the cat's skin is affected by fungi by more than 20-30%, or if the localized mycelium is resistant to treatment, oral ketoconazole is prescribed, as well as fluconazole or itracosol. All these remedies should be used for several weeks, until they disappear completely. clinical signs diseases. A reaction is usually seen after 1-2 weeks of treatment, but therapy should continue for another 3-5 weeks.

Important! These antifungal drugs are very effective, but because of their potentially dangerous side effects and toxicity, they should only be used under the supervision of a competent veterinarian.

In cats.

Malassezia - fungal infection caused by the fungus Malassezia pachydermatis, which is found on the skin of most cats. Usually its presence does not cause any problems, however, in some cases, its amount increases beyond the norm and causes skin disease.

Where can you find Malassezia?

Malassezia can be found on the skin of cats regardless of geographical location. AT usual quantities the presence of the fungus does not cause abnormalities in the health of cats. Malassezia is most commonly present in the ear canals, anal sinuses, vagina, and rectum. The likelihood of cats being infected with Malassezia does not depend on the breed and age of the cat.

How does Malassesia infection occur?

Any hereditary or infection, which weakens immune system skin, may contribute to the development of Malassezia. Primary diseases such as bacterial infections, allergies, seborrhea leading to skin irritation make it more susceptible to Malassezia infection. However, it should be noted that Malassezia infection is rare in cats.

Malassezia symptoms in cats.

Most often, Malassezia manifests itself in hair loss - (alopecia). There may also be acne on the chin, redness and seborrhea.

Diagnosis of malasseziosis in cats.

The best way to diagnose Malassezia is to identify the fungus under a microscope. If malassezia is suspected, samples are taken from the affected areas for analysis (for example, using a special adhesive tape). In most cases of infections, the fungus is present in in large numbers which allows for an accurate diagnosis.

Laboratory culture is also used to identify infection, although this should be kept in mind that Malassezia may be present on the skin. healthy cat. Therefore, there can always be doubts about whether Malassezia is the causative agent of the symptoms. The diagnosis is usually confirmed by the cat's response to treatment.

Treatment of malassezia in cats.

Treatment is carried out in several ways. For a long-term solution to this problem, it is important to correctly identify and treat the underlying disease. Only then does it make sense to start treatment for malassezia.

To create an inhospitable environment for Malassezia, lipids (fats) are removed from the cat's skin. For this, medicated shampoos with chlorhexidine (~ 1%) and shampoos containing benzoyl peroxide and sulfur are used. Human shampoos containing ketoconazole should not be used.

For local treatment small areas apply miconazole ointment, treating the affected area twice a day for several weeks.

In more severe cases, or if the cat is resistant to treatment, ketoconazole, fluconazole, or itraconazole tablets are used. Treatment is also carried out for several weeks. As a rule, improvement appears after 1-2 weeks, however, therapy should be continued for another 3-5 weeks. Oral antifungals are very effective, but they should only be used when directed by a specialist, as they can have a toxic effect on the cat's body.

Conclusion.

Malassezia fungus is often present on a cat's skin without causing disease. AT large quantities, the fungus causes hair loss and is often disguised as an allergy. The fungus can be easily identified and treatment is usually successful. If your cat is shedding hair and not responding to conventional treatments, ask your veterinarian to check her skin for the ubiquitous Malassezia fungus.

Malassezia is a lipophilic yeast that is a symbiotic organism living on the skin and mucous membranes of healthy dogs and cats. Most often, Malassezia is isolated in the area of ​​​​the lips, interdigital folds of the skin, external ear canal, paraanal glands, vagina. Normally, Malassezia closely cooperates with the animal's immunity: it provides special protection to the skin, prevents the penetration of pathogens. The causative agent receives protection and a warm habitat. Pathological reproduction of fungi is facilitated by a violation of the natural resistance of the body and changes in the state of the skin microclimate:

• Change in the intensity of secretion of the sebaceous glands
• Excessive formation of earwax
• Skin inflammatory phenomena
• seborrhea
• Excessive sweating, especially in skin folds
• Immunosuppressive corticosteroid therapy
• Long term antibiotic therapy
• demodicosis
• Hypothyroidism
• Atopic dermatitis
• Non compliance hygiene standards especially in long-eared breeds.

Malassezia is most common in dogs, but is rare in cats. Although it should be noted that Malassezia is a symbionite of almost all warm-blooded animals, including birds.

Breed predisposition in dogs: dachshunds, spaniels, some types of terriers, german shepherds, basset hounds, poodles.

Symptoms

Malassezia dermatitis can be localized or generalized, and is usually accompanied by itching. The degree of itching can be different - from mild to very pronounced. Affected skin is usually reddened, often thickened and darkened. The most common areas for the manifestations of this disease are the ears, groin, interdigital space, neck, chin, axillary areas, skin folds (muzzle, tail). An unpleasant odor from the affected skin may be noticeable. In cats, Malassezia is manifested in hair loss (alopecia), acne on the chin, redness and seborrhea may appear.

Diagnostics

In addition to visual observations, the main way to determine the causative agent of the disease is the sampling skin tests. For the diagnosis of malassiziosis, thin smears are made, dried in air (natural fixation), or fixation is carried out three times through a burner flame. Then the strokes are stained. Sometimes, in hard-to-reach places (interdigital folds), an acetate tape (adhesive tape) can be used to take cytology. In most cases of infections, the fungus is present in large numbers, which makes it possible to accurately confirm the diagnosis. Cultural studies on fungal flora - sowing on Petri dishes are carried out in rare cases to clarify the diagnosis. Indirectly, the diagnosis is confirmed by the response of the animal to treatment.

Treatment

There are several ways to treat. For a long-term solution to the problem, it is necessary to correctly identify and cure the underlying disease that provoked enhanced growth fungal colonies.

To create an unfavorable environment for Malassezia, fats are removed from the animal's skin. For this, they are used medicated shampoos with chlorhexidine, benzoyl peroxide and sulfur. Miconazole ointment has been successfully used for local treatment of small areas. For more severe cases, your doctor may prescribe ketoconazole, fluconazole, or itraconazole tablets. Treatment is usually carried out over several weeks. As a rule, improvements begin to appear after 1-2 weeks of therapy.

The success of the treatment directly depends on the causes of the development of the disease. If the reason lies in the availability various kinds diseases, it is usually enough to eliminate the harmful factors of the external environment, to cure the underlying ailment. Dogs with a breed predisposition will have to wait for life-long treatment with immune-stimulating agents, symptomatic administration of antimycotic drugs. Skin should be processed periodically.