Diagnosis and treatment of autoimmune skin diseases in dogs and cats. Autoimmune eye diseases in animals

Pets, just like people, can get sick from time to time. various diseases. One of the ailments that manifests itself in their skin is pemphigus foliaceus in dogs. Problem this disease in dogs is that in addition to the appearance of wounds on the skin due to allergic reaction on own cells, additional a variety of bacteria which only worsens the course of the disease.

Features of pemphigus disease in dogs

It's one of the autoimmune diseases. skin. This disease is characterized by the production of antibodies by the body against a certain component of adhesion molecules located on keratinocytes. This, in turn, affects the exfoliation of the surface layer of cells on the epidermis.

Among autoimmune diseases, both dogs and cats, pemphigus foliaceus is in the first place among the prevalence. Any dog ​​can develop a problem, regardless of its age, breed or gender. In most cases, veterinarians define the disease in dogs as an idiopathic disease. This means that the etiology of its appearance is not known to them. But at the same time, there is a certain percentage of animals that get sick due to the intake of certain medicines. In addition, in rare cases the appearance of signs of the disease after long-term chronic skin diseases of a different nature was recorded.

The main reason for the development of pemphigus lies in the fact that the dog's body cannot distinguish between virus and bacteria cells with its own body structures. That is why he begins to fight against his own surface layer of the epidermis. The second reason often lies in the fact that the mechanism of sifting out autoreactive lymphocytes at the stage of their maturation is disturbed. Most often, these problems are transmitted genetically. But far from always they appear in all animals with poor heredity. The predisposing factors for this are:

• ultraviolet irradiation;
• infectious diseases;
• uncontrolled drug treatment;
• exposure to certain chemicals.

The disease may appear different ways. This applies both to the localization of lesions and the degree of intensity of the formation of pustules and papules. Significant deterioration of the condition of the animal can occur after any additional pathogen enters the wound surfaces. This can start a secondary infection which can make clinical picture disease more confusing.

Clinical signs

Initially, when pemphigus foliaceus develops in dogs, various papules and pustules develop on their skin. But they are quite difficult to detect due to the fact that they are hidden due to a rather thick coat. In addition, these formations are quite fragile, which is why, due to various mechanical damage they break through.

As secondary features diseases, veterinarians determine the formation of erosions, crusts yellow color, epidermal collars, as well as areas of prolapse hairline. This occurs in places where before there were papules and pustules.

The development of symptoms of the disease can occur quite quickly or gradually. In the first case, the process takes from one to two weeks. It is often characterized by some systemic features such as depression, fever, anorexia, and an increase in the dog's lymphatic flow. When gradual development pemphigus, the dog tolerates the disease more easily, since more than a month passes between the appearance of the first imperceptible and subsequent noticeable signs. There are certain zones of localization of skin lesions. They are such places of the dog's body as:

• back of the nose;
• nasal mirror;
• eyelids;
• ears and areas near them;
• paw pads;
• ventral surface of the abdomen.

Mostly the disease begins on the muzzle in dogs. After several weeks of progression, it becomes more generalized. When diseases long time present on the skin of the animal, it begins the process of depigmentation. The mucous membranes of the mouth or nose with pemphigus, as a rule, are not affected. It is worth noting one more feature this disease- the process has a clear symmetrical nature of occurrence, as in many other autoimmune diseases.

Diagnosis of the disease

Diagnosis requires careful analysis and exclusion of many other diseases. Among them, veterinarians distinguish diseases such as:

1. superficial pyoderma;
2. dermatophytosis;
3. some other ailments of the autoimmune spectrum of occurrence;
4. subcorneal pustular dermatosis;
5. eosinophilic pustulosis;
6. medicinal dermatosis;
7. dermatomyositis;
8. zinc sensitive dermatosis;
9. cutaneous epitheliotropic lymphoma;
10. hepatocutaneous syndrome;
11. hypersensitivity to insect bites.

Only after all of the above diagnoses are excluded, the doctor can determine that the problem lies precisely in pemphigus. The complexity of determining the disease lies in the fact that in most cases the etiology of the disease is unclear. To confirm the diagnosis, it is necessary to pass certain tests, among which there are the following types surveys:

1. It is necessary to conduct a cytological analysis of the pustule. Neutrophils and acantholytic cells will be noticeable in it. Sometimes the laboratory assistant can detect eosinophils in the preparation.
2. You need to test for antinuclear antibodies. With pemphigus, it should give a negative result.
3. But the problem often lies in the unreliability of the data obtained. If carried out only given type surveys can be obtained false positive result which makes it difficult to determine the real disease.
4. A dermatohistopathology should be performed. It can confirm cytological analysis by detecting subcorneal pustules containing neutrophils with varying numbers of eosinophils.
5. You can confirm the disease with a biopsy of the affected skin. The dog body preparation is sent for immunofluorescence or immunohistochemistry. Its characteristic feature is the intercellular deposition of antibodies. It should be understood that false positive and false negative results are not uncommon.

In the event of a secondary infection, it is worth conducting an analysis to detect bacterial culture in the void. If the result is sterile, then the dog has only one disease, if any pathogen is detected, then treatment will be difficult, since it will be necessary to deal with two problems.
The above diagnostic methods allow you to establish a diagnosis. It is far from always necessary to carry out all types of examinations, since only one reliable result is sufficient. It will be informative about flux in a dog.

Treatment of the disease

Veterinarians recommend immunosuppressive doses of prednisolone as the main type of treatment for this disease in dogs. At the very beginning of the treatment of the disease, it is required to give the pet 2-6 milligrams of the drug per kilogram of weight. This treatment lasts up to two weeks. After that, a single dose is gradually reduced over 1-1.5 months.

It should be noted that the initial dose, duration of treatment, as well as the duration of remission of the disease depends on many factors. Among them, it is worth highlighting the age of the dog, its breed, gender, etc. That is why each doctor should select the type of therapy individually, taking into account all the characteristics of the animal.

Sometimes it happens that prednisolone is ineffective against pemphigus foliaceus. In such cases, doctors prescribe alternative types of drugs, which are corticosteroids. Among them, Triamcinolone and Dexamethasone are most often used. It is believed that the ultimate goal of treatment is to switch to the use of drugs at a dose of 1 milligram per 1 kilogram of the dog's weight.

If the therapy of dogs is carried out in a mono mode, to the action of which there is no corresponding reaction of the body, Azathioprine is also added to the drug used. When it is possible to achieve control over the clinical manifestations of the disease, these drugs are reduced to the lowest possible dose. As a result, they begin to give them to the pet every other day - first Prednisolone, then Azathioprine.

In the case when the above means do not give any results, some others can be used. Among them, the following drugs are effective:

• Chlorambucil;
• Cyclophosphamide;
• Cyclosporine.

Unlike cats, these medications do not cause too strong symptoms in dogs. adverse reactions, which makes them quite easy to use. If infection with a secondary infection occurs at the sites of formation of papules and erosions, then the animal should be systemic therapy with antibacterial effect. It is best to use drugs with a narrow spectrum of action. To do this, it is very important to determine the pathogen that the dog picked up. It is also important to note that in addition, local therapy for pemphigus in pets can be carried out. medicines based on corticosteroids.

It should also be noted that the treatment of the disease should be as adequate as possible. It is not worth raising the dose of immunosuppressants taken by animals too much. It is believed that it is better not to completely control the clinical manifestations of pemphigus than to give the dog a lot of different drugs.

Possible forecast

One of the main problems of therapy for the disease is that its results can be very diverse. There are three most likely scenarios:

1. Treatment allows you to achieve a satisfactory lifestyle of the animal with a life-long intake of small doses of drugs.
2. Treatment allows you to achieve complete remission without the need to take drugs.
3. The treatment does not achieve any adequate result, as a result of which the dog is best succumbed to the process of euthanasia. This is mainly due to the fact that the pet will feel discomfort all the time with pemphigus and discomfort. In addition, throughout the life of the dog there will be a high risk of developing a secondary infection, which can provoke even more significant problems with the skin.

It is worth noting that in cats, unlike dogs, the treatment of pemphigus foliaceus is in most cases more favorable.

Conclusion

In order to achieve remission of any disease in dogs, it is necessary to carefully treat the health of your pets, in necessary cases to be examined by a veterinarian, as well as to notice any changes in their behavior in time. Only in such cases can a good result be achieved. The disease has quite effective treatment, but at the same time it is far from always possible to rely on it. Disease in certain cases is completely unpredictable, which can lead to the death of the animal or a significant deterioration in its state of health. To prevent this, you should always watch your pet and at the first sign, contact the veterinarian.

Paul B Bloom 1.2
1. Clinic of Allergology, Skin and Ear Diseases of Pets, Livonia, USA
2. Faculty clinical veterinary medicine Small Animals, Department of Dermatology, Michigan State University, USA

Diagnosis of any skin disease is based on a thorough history taking, clinical manifestations(primary localization, nature and distribution of elements), laboratory tests and response to treatment. The most valuable laboratory technique for autoimmune skin lesions is histological examination. But even this can lead to confusion if tissue samples are taken inappropriately.

Pemphigus (pemphigus)

With pemphigus the immune system mistakenly attacks desmosomes. Desmosomes are point-to-cell contacts connecting, in particular, keratinocytes.

Pemphigus exfoliative (EP) is the most common form of pemphigus and probably the most commonly diagnosed autoimmune disease skin in dogs and cats. Other forms of pemphigus encountered in practice include pemphigus erythematous and panepidermal pemphigus. Basically, EP affects young and adult animals with an average age of onset of 4 years. Sixty-five percent of dogs become ill before the age of 5. EP has been described in many breeds, but the author's experience shows that increased risk occurrence of this disease in Chow Chow and Akita. There was no relationship between incidence and gender.

Three forms of EP are described in the literature - spontaneous pemphigus, drug-associated (both drug-induced and drug-induced) and a form associated with chronic disease skin, but the latter is extremely rare in practice. This observation is based on the experience of the author, and there is no evidence for it. The vast majority of cases are spontaneously occurring disease.

When taking the history, the owner may report that the features wax and wane, that the progression of the disease was slow (especially in cases with localization exclusively on the face), or that the features appeared acutely (most often with a generalized lesion). With generalization, dogs often have a fever, swelling of the limbs and common signs. Itching in any form may be absent, and may be moderate.

There are three patterns of primary spread of EP:

1. facial form (the most common), in which the bridge of the nose, nose, periorbital zone, auricles are affected (especially in cats);
2. plantar form (only paronychia can be observed in cats);
3. a generalized form in which elements appear on the muzzle and then spread (note - in dogs, elements sometimes appear all over the body at once).

Elements go through the following stages of development: erythematous spot pustule annular ridge (“collar”) erosion yellow-brown crust. Because of the involvement hair follicles often there is a multifocal or diffuse alopecia.

The primary element of EP are large pustules not associated with follicles (pustules are also present in the follicles) most often on the bridge of the nose, paw pads, nose and auricles(in cats, elements can be localized around the nipples). By comparison, pustules in bacterial pyoderma are localized in follicles, located on the abdomen and/or trunk, and are much smaller. Secondary elements in cats and dogs are observed much more often. These include epidermal collars, yellow-brown crusts, and erosions. They may be accompanied by systemic involvement, distal limb edema, fever, drowsiness, and lymphadenopathy.

The differential range includes any disease with pustules, crusting, and scaling, eg, pemphigus erythematosus, zinc-deficient dermatosis (especially with footpad involvement), metabolic epidermal necrosis (especially with footpad involvement), bacterial and fungal (dermatophytosis) infections, and demodicosis. , discoid lupus erythematosus (DLE) (facial / nasal form), erythema multiforme, mycosis, leishmaniasis and inflammation of the sebaceous glands.

Diagnostics

A cytological preparation of a pustule or crust should be made. Microscopy will show acantholytic keratinocytes, either single or in clusters, surrounded by normal neutrophils and/or eosinophils in the absence of bacteria. The only method confirming pemphigus is histology. A biopsy should be taken from an intact pustule or, in its absence, from a crust. Proteases of bacteria (with pyoderma) or dermatophytes (Trichophyton mentagrophytes) destroy intercellular glycoproteins (desmoglein), leading to acantholysis. Since these infectious diseases are very similar to EP histologically, special staining for both bacteria (Gram) and fungi (GMS, PAS) should be used when making a biopsy diagnosis. The author routinely performs dermatophyte cultures in all cases of suspected EP.

Forecast

EN can be caused or provoked by drugs (in last case latent disease is detected by a reaction to the drug). Drug-induced EN resolves after discontinuation of the drug and a short course of immunosuppressants.

Drug-induced EN occurs when a drug stimulates genetic predisposition organism to the development of EP. Usually this form of EN should be treated as idiopathic EN. There is currently no way to determine whether drug-associated EN is drug-induced or drug-induced. In fact, there is no test to predict how well EN will respond to treatment other than the treatment itself.

A study at the University of North Carolina (USA) found that six out of 51 dogs with EN were able to stop all treatment, after which remission lasted more than 1 year. The author has seen many cases (not drug-associated) in which long-term (lifelong) remission was achieved by slow withdrawal of drugs. This clinical observation is supported by a recent study in which 6 of 51 dogs with EN were able to achieve long-term remission without medication. Interestingly, these dogs were from high exposure areas. ultraviolet radiation(North Carolina or Sweden).

In this group of dogs, it took 1.5–5 months of treatment to achieve remission. The drug(s) was slowly canceled until the complete cessation of treatment. The total duration of immunosuppressive therapy varied between 3 and 22 months. These dogs remained in remission for the entire follow-up period (1.5–6 years after treatment).

A study performed at the University of Pennsylvania (USA) showed that dogs with EP had a longer life expectancy when antibiotics (usually cephalexin) were used in addition to immunosuppressants. This is contrary to the clinical observation that dogs with EP do not develop concomitant pyoderma until they are started on immunosuppressive therapy. Moreover, another recent study found no difference in survival when antibiotics were used in initial therapy.

In a University of Pennsylvania study, survival was approximately 40%, with 92% of deaths occurring in the first year. In the same results, 10% of cases ended in long-term remission after drug withdrawal. In other researchers, long-term remission was achieved in about 70%.

Cats have a better prognosis for this disease than dogs. In the same University of Pennsylvania results, only 4 out of 44 cats died (from disease or treatment) during the entire study period. According to the author's experience, the annual survival rate exceeds 90%. In addition, a significant number of cats do not relapse after discontinuation of all medications.

Treatment

Treatment of any autoimmune skin disease requires frequent monitoring and vigilance for complications associated with immunosuppressive therapy, such as demodicosis, dermatophytosis, and bacterial pyoderma. Interestingly, the author has rarely seen a dog with EP present with secondary pyoderma on first examination. It develops much more often after the start of immunosuppressive therapy. If the patient was under control and relapsed, or the patient you are trying to get into remission gets worse, there are two possible reasons. The first is an exacerbation of EP (with an increase / decrease in elements), and the second is a secondary infection due to immune suppression. If new elements are located in the follicles, three folliculotropic infections should be excluded - bacterial, demodicosis and dermatophytosis. The minimum examination that should be carried out when such elements appear: skin scrapings, Wood's lamp examination (screening) and impression smears. Whether or not to do fungal culture at this point depends on how often you encounter dermatophytosis in your practice, and on the results of cytology (acantholytic keratinocytes, cocci, demodex). If dermatophytosis is common in your practice, culture should be done. Otherwise, culture for fungi and a second skin biopsy are performed as a second step if there is no adequate response to treatment.

In addition to the treatments described below, symptomatic therapy should include medicated shampoo. Since EN is clinically indistinguishable from superficial bacterial folliculitis, the author prescribes cephalexin (10–15 mg/kg 2–3 q/d) until histological results are available, unless EN is suspected to be caused by cephalexin.

There is no “best” treatment that works for all cases of EN, so treatment must be individualized.

For this reason, it is extremely important to self-examine the dog or cat before any adjustment in therapy and to monitor the course of the disease in detail. When planning treatment, the severity of the condition should be assessed to ensure that treatment does not more harm than the disease itself.

There are regional differences in the degree of aggressiveness of EN treatment. Some of them are associated with a different gene pool. Since EP worsens under the influence of sunlight, they may also be related to differences in daylight hours. In any case, avoiding sunlight is part of the treatment for EN.

Because diet is known to be a cause of (endemic) EP in humans, in the event of a poor response to initial therapy, the author reviews the dietary history and makes dietary adjustments. In humans, thiols (garlic, onion), isothiocyanates (mustard, horseradish), phenols ( nutritional supplements) and tannins (tea, bananas, apples). Vitamin E (400-800 IU 2 times a day) and essential fatty acid due to their anti-inflammatory and antioxidant properties.

The basis for the treatment of autoimmune skin diseases are glucocorticosteroids (GCS). They can be applied both locally and systemically, depending on the severity of the disease and the area of ​​the lesion. Because some cats cannot metabolize inactive prednisone to active form, prednisolone, in cats, prednisone alone should be used. In dogs, both can be used. The author observed cases of EP in cats that were well controlled on prednisolone, but relapsed on prednisolone and returned to remission only after re-prescribing prednisolone - all at exactly the same dosage.

The most powerful veterinary local preparation is a synotic containing fluocinolone acetonide. If the disease is localized, the author prescribes the drug 2 times a day. until clinical remission is achieved (but not more than 21 days), and then slowly cancels over several months. Make sure the owner wears gloves when applying this medication.

Dogs with more severe disease prednisone or prednisolone is prescribed at a dose of 1 mg/kg 2 times a day. for 4 days, and then by mg / kg 2 r. / d. for the next 10 days. Re-examinations are carried out every 14 days. If remission is achieved, the dose is reduced by 25% every 14 days. The author defines remission as the absence of active (fresh) elements (no pustules, and any crusts are easily removed, and the underlying epidermis looks pink and without erosion). You can not reduce the dose too quickly! The goal is to keep the dog on 0.25 mg/kg or less every other day. If this is not achievable, azathioprine is added to therapy (see below).

Some dermatologists use combination therapy from the outset, but in the author's experience, at least 75% of dogs can be maintained exclusively on corticosteroids, with additional risks and costs associated with the use of azathioprine. Only in the absence of a response to corticosteroids or in case of insufficient use every other day should azathioprine be added to the treatment.

For the treatment of cats, only prednisolone is used. In fact, only prednisolone can be found in the author's first aid kit - in order to avoid inadvertently giving prednisone to a cat. Dose for cats 1 mg/kg 2 times a day. within 14 days. The prednisolone regimen for cats is then similar to that for dogs. If it is not possible to control the disease on prednisolone, chlorambucil (not azathioprine!) is added to therapy.

If the animal does not respond to prednisolone, other immunosuppressive agents must be added (see below).

Animals receiving GCS for a long time, regardless of the dose, require monitoring of general and biochemical blood tests, general analysis urine and urine culture (to rule out asymptomatic bacteriuria) every 6 months.

Azathioprine is an antimetabolite, a competitive purine inhibitor. Purine is necessary for normal DNA synthesis, therefore, in the presence of azathioprine, defective DNA is synthesized, which prevents cell division. The action of azathioprine reaches full force with a delay of 4-6 weeks. The drug is prescribed simultaneously with GCS. Initial dose of azathioprine 1.0 mg/kg 1 r./d.

After achieving remission and stopping or reducing GCS to minimal doses, azathioprine intake is reduced every 60-90 days. The author usually reduces not the dose, but the frequency of administration, first appointing every other day, and then 1 time in 72 hours. General (with platelet count) and biochemical analysis blood counts are monitored every 14 days for 2 months, then every 30 days for 2 months, then every 3 months for the entire duration while the dog is on azathioprine. Possible side effects include anemia, leukopenia, thrombocytopenia, hypersensitivity reactions (especially in the liver), and pancreatitis. Azathioprine should not be given to cats as it can cause irreversible bone marrow depression.

Cats and dogs that do not respond to or cannot tolerate azathioprine should be treated with chlorambucil. The treatment regimen/precautions/monitoring for chlorambucil is the same as for azathioprine. Initial dose 0.1-0.2 mg/kg/day.

The combination of tetracycline and niacinamide has many anti-inflammatory and immunomodulatory properties and is therefore often used to treat a variety of immune-mediated conditions. skin diseases such as DLE, vesicular cutaneous lupus erythematosus (idiopathic ulcerative lesion collie and sheltie skin), lupus onychodystrophy, erythematous pemphigus, metatarsal fistula german shepherds, aseptic panniculitis, aseptic granulomatous dermatitis (idiopathic aseptic granuloma-pyogranuloma syndrome), vasculitis, dermatomyositis and cutaneous histiocytosis. The author uses this combination for all these diseases, if they are relatively mild. If any of these diseases do not respond to immunosuppressive therapy, dogs can be treated with this combination. The dosage of tetracycline and niacinamide for dogs less than 10 kg - 250 mg of both every 8 hours, for dogs heavier than 10 kg - 500 mg of both every 8 hours. With a clinical response (which usually takes several months), the drugs are slowly withdrawn - first up to 2, and then up to 1 r / day. Side effects are rare, and when they occur are usually caused by niacinamide. These include vomiting, anorexia, drowsiness, diarrhea, and increased liver enzymes. Tetracycline may lower the seizure threshold in dogs. In cats, it is preferable to use doxycycline at a dose of 5 mg/kg 1-2 times a day. Doxycycline should be given to cats in either liquid or tablet form, but be sure to give 5 ml of water afterwards. The use of doxycycline can lead to esophageal strictures in cats!

If the above treatment fails in dogs, cyclosporine A, a calcineurin inhibitor, is given orally at a dose of 5 mg/kg bid. Also described isolated cases successful treatment of EP in cats (especially ungual form). Recently there was a message about the effectiveness local application tacrolimus in the treatment of facial epilepsy and pemphigus erythematosus. Experience with the use of this drug by the author is insufficient.

A specific approach may be applied to mild cases of facial EN (or pemphigus erythematosus): topical corticosteroids and/or tetracycline-niacinamide. With generalized forms or with severe course facial / plantar forms, prednisolone should be used according to the scheme described above. While remission is established at each examination, the dose of prednisolone is gradually reduced, as described above. If at the control examination after 14 days remission is not achieved or it is not stable at the dose of hormones<0,25 мг/кг каждые 48 часов, тогда в лечение добавляются азатиоприн (у собак) или хлорамбуцил (у кошек).

If the disease does not respond to treatment, make sure the diagnosis is correct (make sure that dermatophytosis, demodicosis and bacterial pyoderma are excluded).

If the diagnosis is confirmed, try switching to dexamethasone or triamcinolone. The initial dose is 0.05-0.1 mg/kg 2 times a day, and then reduced in the same way.

As a last resort in refractory cases of EN, pulsed corticosteroid therapy at high doses is successful. After pulse therapy, prednisolone is continued at a dose of mg/kg 2 times a day. with a gradual decrease.

There are two pulse therapy protocols:

1. 11 mg/kg of methylprednisolone sodium succinate (per 250 ml of 5% glucose) i.v. 1 p./d. 3-5 days;
2. 11 mg/kg prednisone po bid 3 days.

Discoid lupus erythematosus (DLE)

The approach to diagnosing DLE is the same as for EP, taking into account the dog's individual characteristics, history, physical examination, histological examination, and response to treatment. In dogs, DKV is the second most common autoimmune skin disease. The author has never seen it in cats. According to the literature, there is no relationship of the disease with age, but according to the author's experience, it is more common among young and adult dogs. Some dermatologists list Collies, Shelties, German Shepherds, Siberian Huskies, and Breton Spaniels as high-risk breeds.

Clinical manifestations include depigmentation, erythema, erosions, crusting, and alopecia. When the nose is involved, it loses its cobblestone texture and becomes bluish-gray. DLE usually begins on the nose and may extend to the bridge of the nose. In addition, the lips, periorbital zone, auricles and genitals can be affected. The well-being of dogs does not suffer.

DLE should be differentiated from mucocutaneous pyoderma, pemphigus, skin reaction to drugs, erythema multiforme, cutaneous lymphoma, Vogt-Koyanagi-Harada syndrome (neurodermatouveitis), systemic scleroderma, solar dermatitis, and fungal infections.

Mucocutaneous pyoderma (the author adheres to the term "antibiotic sensitive dermatitis" because bacteria are not detected on histology) is a disease that affects the lips, nose, bridge of the nose, periorbital zone, genitals and anus. Clinically, it is indistinguishable from DKV. There is no identifiable cause for this disease, so the diagnosis is based on the characteristics of the dog (adult, most often a German Shepherd or its cross), the clinical presentation (type and distribution of elements) and, most importantly, response to antibiotic therapy. In the past, it was differentiated from DLE by histological findings. DLE was then defined by lichenoid lymphocytic or lymphocytic plasma cell superficial dermatitis with hydropic degeneration and/or isolated necrotic keratinocytes involving the basal cell layer. There was pigment incontinence and basement membrane thickening. Mucocutaneous pyoderma was determined by lichenoid plasma cell or lymphocytic plasma cell infiltration without surface changes and damage to the basal cell layer. However, these criteria have been called into question after a recent study, the results of which showed that DLE and mucocutaneous pyoderma can be histologically indistinguishable! In this study, dogs were divided on the basis of histological findings into three groups: with lymphocytic lichenoid superficial dermatitis with hydropic degeneration, with plasma cell lichenoid dermatitis, and mixed with lymphocytic plasma cell lichenoid superficial dermatitis with hydropic degeneration. The authors then determined how different groups responded to treatment with antibiotics or immunomodulators. There was no statistical difference in histological features between groups II and III! The author now takes the view that in all cases of nasal dermatitis in dogs, a 30-day course of cephalexin should be given before immunomodulatory therapy. In fact, a 3-4 week course of cephalosporins before a biopsy is justified and often makes it possible to establish a diagnosis without a biopsy!

The best approach to nasal dermatitis that is clinically similar to "typical" DLE is to understand that it is more of a reaction pattern than a disease. This pattern (lymphocytic plasma cell lichenoid dermatitis of the nasal region) may respond to antibiotics or require immunomodulatory therapy. Since the results of the biopsy are identical, it would be correct to prescribe a 30-day trial course of cephalosporin before the biopsy.

Diagnostics

Dogs with DLE are clinically healthy. Hematological or serological changes are not noted (including a negative analysis for ANA). Historically, lymphocytic or lymphocytic plasma cell lichenoid superficial dermatitis with hydropic degeneration of basal keratinocytes has been considered characteristic of the histological changes in DLE. Scattered apoptotic keratinocytes may be present.

Treatment

When treating dogs with DLE, it is important to understand that this is primarily a cosmetic condition. Sometimes dogs are bothered by itching. In this light, it is important to treat each case according to the severity of the symptoms. You must be sure that the treatment will do no more harm than the disease itself. The author treats DKV in stages, each new appointment being added to the previous one, unless otherwise indicated. Initially, cephalexin 10-15 mg/kg 2 times a day is prescribed. within 30 days (given that DKV and mucocutaneous pyoderma are indistinguishable). If the dog does not respond to cephalexin, it is stopped and the following are given: avoidance of sunlight, UV protection, vitamin E and omega-3 fatty acids. Niacinamide and tetracycline are prescribed according to the scheme described above. If after 60 days the dog does not respond to treatment, the next step is to assign local corticosteroids (starting with moderately strong). If there is no response after 60 days, tetracycline and niacinamide are withdrawn and systemic prednisolone (anti-inflammatory doses) is given, which is then slowly withdrawn over several months until the lowest possible dose is reached.

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Prepared according to the materials: "PROCEEDINGS OF THE MOSCOW INTERNATIONAL VETERINARY CONGRESS, 2012

AUTOIMMUNE DISEASES OF THE SKIN IN CATS AND DOGS ON THE EXAMPLE OF VELICLES. CAUSES, CLINICAL SIGNS, DIAGNOSIS, TREATMENT

Semenova Anastasia Alexandrovna

2nd year student, Department of Veterinary Medicine and Animal Physiology, KF RGAU-MSHA named after V.I. K.A. Timiryazev, Russian Federation, Kaluga

Beginina Anna Mikhailovna

scientific supervisor, Ph.D. biol. Sciences, art. Lecturer KF RGAU-MSHA, Russian Federation, Kaluga

As you know, in addition to the usual immunity responsible for protecting the body from foreign elements, there is autoimmunity, which ensures the utilization of old and destroyed cells and tissues of one's own body. But sometimes the immune system begins to "attack" the normal cells and tissues of its own body, resulting in an autoimmune disease.

Autoimmune skin diseases are a very understudied area in veterinary medicine. A small percentage of morbidity causes poor knowledge of these diseases and, as a result, the wrong diagnosis and the choice of the wrong treatment by veterinarians.

One of these diseases are diseases of the pemphigoid complex (pemphigus).

Several types of pemphigus have been found in animals:

Pemphigus foliaceus (PV)

Erythematous pemphigus (EP)

Pemphigus vulgaris

Vegetative pemphigus

Paraneoplastic pemphigus

Hailey-Hailey disease.

The most common in animals are leaf-shaped and erythematous pemphigus.

Pemphigus is an organ-specific autoimmune disease. The pathogenesis of this type of diseases is based on the formation of autoantibodies to tissue and cellular structures of the skin. The type of pemphigus is determined by the predominant type of antibodies.

Causes

The exact causes of this disease have not been fully established. Most veterinarians who have encountered this disease note that severe stress, prolonged exposure to the sun aggravates the course of the disease and, possibly, can also cause pemphigus. Therefore, if symptoms of pemphigus occur, it is recommended to exclude (or minimize) the exposure of the animal to the sun.

Some researchers in their articles indicate that pemphigus can be caused by the use of certain drugs, such as Methimazole, Promeris and antibiotics (sulfonamides, Cefalexin). Another common point of view is that the development of the disease can occur as a result of other chronic skin diseases (eg, allergies, dermatitis). However, there is no evidence or research to support this view.

One of the causes of the disease can be identified genetic predisposition. In medicine, a number of studies have been done, during which it was found that the next of kin of a patient with an autoimmune disease has an increased amount of autoantibodies. Based on the fact that some breeds are more susceptible to the disease, it can be concluded that the disease is inherited in animals.

Pemphigus can occur as a result of drug stimulation of the body's genetic predisposition to develop pemphigus.

At the moment, there is no way to find out whether pemphigus is spontaneous or provoked.

Pemphigus foliaceus(Pemphigus foliaceus).

Figure 1. Scheme of the location of lesions on the head in LP

First described in 1977, it occurs in 2% of all skin diseases. Breed predisposition in dogs: Akita, Finnish Spitz, Newfoundland, Chow Chow, Dachshunds, Bearded Collie, Doberman Pinscher. There is no breed predisposition in cats. Animals of middle-aged age get sick more often. No relationship of incidence with gender was noted. In addition to dogs and cats, horses are also affected.

According to the causes of occurrence, pemphigus is most often divided into forms: spontaneous (the greatest predisposition is noted in Akita and Chow Chow) and drug-induced (predisposition is noted in Labradors and Dobermans).

Clinical manifestations. The skin of the back of the nose, ears, crumbs of the feet and the mucous membranes of the mouth and eyes are usually affected. Other parts of the body may also be affected. Lesions in LP are unstable and may progress from erythematous macules to papules, from papules to pustules, then to crusts, and appear intermittently. Damage

Figure 2. Scheme of the location of lesions on the trunk and extremities in LP

accompanied by alopecia and depigmentation of the attacked areas. Of the systemic manifestations, anorexia, hyperthermia, and a depressed state are encountered.

A characteristic feature is large, unrelated follicle pustules (follicle pustules may also be present).

Erythematous (seborrheic) pemphigus(Pemphigus erythematosus)

Mostly dogs of dolichocephalic breeds are ill. Breed or age predisposition of cats is not marked. Lesions are limited, as a rule, to the back of the nose, where erosions, crusts, abrasions, ulcers are found, sometimes pustules and blisters, as well as alopecia and depigmentation of the skin. This type of pemphigus can be considered a milder form of LP. With inappropriate or untimely treatment, it can turn into a leaf-shaped form of pemphigus.

Pathogenesis

Similar in both erythematous and pemphigus foliaceus. The pathogenesis of this is the formation of autoantibodies against surface antigens of epidermal cells, as a result of which immune responses are activated, leading to acantholysis (breakdown of connections between epidermal cells) and exfoliation of the epidermis. Acantholysis results in vesicles and pustules that often coalesce to form blisters.

Establishing diagnosis

The diagnosis is made on the basis of anamnesis, clinical manifestations, trial antibiotic therapy. However, it is impossible to make an accurate diagnosis of an autoimmune skin disease based only on clinical signs due to the similarity of many dermatological diseases, both autoimmune and immune-mediated diseases, as well as due to the addition of secondary infectious diseases of the skin. Therefore, it is advised to do more in-depth studies such as cytology and histology to detect and control secondary infectious diseases.

Cytology

This test can be a definitive diagnosis. A characteristic feature of pemphigoid diseases is the presence of a large number of acanthocytes accompanied by neutrophils. Acanthocytes are large cells, 3-5 times the size of neutrophils, also known as acantholytic creatinocytes. Acantholytic creatinocytes are epidermocytes that have lost contact with each other as a result of acantholysis.

Histopathology

In LP, early histopathological signs are intercellular edema of the epidermis and destruction of desmosomes in the lower parts of the germ layer. As a result of the loss of communication between epidermocytes (acantholysis), first gaps are formed, and then bubbles are located under the stratum corneum or granular layer of the epidermis.

With proper biopsy, it is possible to make an accurate diagnosis, as well as to identify secondary infectious diseases. When conducting a biopsy, dermatologists advise taking at least 5 samples. In the absence of pustules, a biopsy of papules or spots should be taken, as they may contain micropustules. Since some diseases are histologically similar to pemphigus (pyoderma, ringworm), Gram stain (for bacteria) and fungal stain (GAS, PAS) should be used.

Repeated studies are done in the absence of a response to treatment, as well as in case of repeated relapse.

In order to make sure that there are no secondary infectious diseases, be sure to do a dermatophyte culture and examine the animal in a Wood's lamp.

Differential diagnoses: Demodicosis, Dermatophytosis, Discoid lupus erythematosus (DLE), Subcorneal pustular dermatosis, Pyoderma, Leishmaniasis, Sebadenitis.

Treatment.

Treatment of autoimmune skin diseases involves modifying or regulating immunological responses through pharmacotherapy. It comes down to achieving remission and maintaining it.

The main drugs are glucocorticoids.

Before choosing this treatment regimen, it is necessary: ​​to keep in mind that the treatment is carried out with glucocorticoids and immunosuppressants, and therefore it is necessary to accurately diagnose and know possible side effects and methods for their prevention; know about the presence of any diseases in the animal, in which treatment with glucocorticoids is contraindicated.

Prednisolone is usually given to dogs at doses of 1 mg/kg every 12 hours. If there is no improvement within 10 days, the dose is increased to 2-3 mg/kg every 12 hours. After achieving remission (approximately after a month or two), the dose is gradually reduced to 0.25-1 mg / kg every 48 hours. Cats are prescribed Prednisolone at doses of 2-6 mg/kg per day, gradually decreasing to a minimum. Prednisolone requires activation in the liver, so it is used only orally.

In about 40% of cases of diseases in dogs, when remission is achieved and the dose is gradually reduced, it is possible to completely cancel the drug, returning to it only during exacerbations.

In veterinary medicine, only five glucocorticoid agents with different dosage forms, duration of action and additional drugs are officially allowed to be used. It must be borne in mind that the treatment is long and in accordance with this, select the drug. It is important to remember that glucocorticoids have a metabolic inhibitory effect on the hypothalamus-pituitary-adrenal cortex relationship, which leads to atrophy of the adrenal cortex. Therefore, it is worth choosing a drug with an average duration of the biological effect, so that after achieving remission, with the introduction of the drug every 48 hours, the body has the opportunity to recover, thus reducing the likelihood of complications. For this reason, Prednisolone or Methylprednisolone is usually used, since their duration of biological effect is 12-36 hours.

Methylprednisolone has minimal mineralocorticoid activity, so it is advisable to prescribe it, for example, in the case of polyuria-polydipsia syndrome. This drug is prescribed in doses of 0.8-1.5 mg/kg 2 times a day until remission is achieved, then reduced to a maintenance dose of 0.2-0.5 mg/kg every 48 hours.

Glucocorticoids can increase K + excretion and decrease Na + excretion. Therefore, it is necessary to monitor the state of the kidneys, adrenal glands (due to inhibition of the relationship between the hypothalamus-pituitary-adrenal cortex and subsequent atrophy of the adrenal glands) and control the level of K in the body.

Sometimes the use of glucocorticoids alone is not enough. Therefore, to achieve the best effect, cytostatics are used together with glucocorticoids. The most commonly used dose of azathioprine is 2.2 mg/kg every day or every other day in combination with an adequate dose of glucocorticoid. When remission is achieved, the doses of both drugs are gradually reduced to the minimum effective, which is administered every other day. For cats, Azathioprine is a dangerous drug, because it strongly suppresses the activity of the bone marrow. Instead, Chlorambucil is prescribed in doses of 0.2 mg / kg.

In addition to Azathioprine and Chlorambucil, Cyclophosphamide, Cyclosporine, Cyclophosphamide, Sulfasalazine, etc. are used.

Among the side effects of combined treatment with glucocorticoids and cytostatics, vomiting, diarrhea, suppression of bone marrow function, and pyoderma are distinguished. A hepatotoxic effect may occur due to the toxic effect of azathioprine (the activity of liver enzymes increases), so it is worth using azathioprine with hepatoprotectors. The use of Prednisolone (at doses of 1-2 mg / kg) and Cyclosporine increases the risk of tumors.

Chrysotherapy (treatment with gold preparations) is also used in the treatment of pemphigus. According to American researchers, it is effective in 23% of cases in dogs and in 40% of cases in cats. Used as monotherapy with gold salts, and in combination with chrysotherapy with glucocorticoids.

Myocrysin is administered intramuscularly in initial doses of 1 mg (for cats and dogs weighing less than 10 kg) and 5 mg (for animals weighing over 10 kg) once a week. The dose is doubled if there are no side effects within seven days. In the absence of side effects, treatment is continued at doses of 1 mg/kg once a week.

In addition to Myokrizin, the use of the drug Auranofin is described in veterinary medicine. It has fewer side effects and is more suitable for long-term treatment, because. is administered orally. Use Auranofin in doses of 0.02-0.5 mg/kg every 12 hours orally. The drug is more easily tolerated by animals, side effects are less common.

Forecast in these diseases is unfavorable. More often, if left untreated, it is fatal. The prognosis for drug-induced pemphigus may be positive with discontinuation of the drug and a short course of immunosuppressants.

There are cases in which, after discontinuation of drugs, remission lasted more than one year and even for life. According to studies at the University of Pennsylvania, 10% of dog cases ended in long-term remission after drug withdrawal. Similar results were obtained by scientists at the University of North Carolina. Other researchers noted long-term remission after discontinuation of drugs in 40-70% of cases.

The highest mortality rate (90%) was found in patients during the first year of the disease.

Cats have a better prognosis for this disease than dogs. Cats with pemphigus have a higher survival rate and fewer cats relapse after all drugs are stopped.

Private clinical case

Anamnesis . Dog breed Black Russian Terrier, 45 kg. The first symptoms appeared at the age of 7. First, the mucous membranes of the eyes became inflamed, then, after a few days, the dog refused to eat. Inflammation of the gums was found. At the same time, lesions (pustules) appeared on the crumbs of the paws and the back of the nose. An increase in temperature and a depressed state of the animal were noted.

Cytological and histological studies of pustules taken from the crumbs of the paws and the back of the nose were carried out. As a result, a diagnosis of Pemphigus foliaceus was made.

Prednisolone was used for treatment at a dose of 25 mg every 24 hours for 4 days. Then within a week the dose was increased to 45 mg. Prednisolone was co-administered with Potassium Orotate (500 mg) orally. A week later, the dose of Prednisolone was gradually (over two weeks) reduced to 5 mg every 24 hours. And then, after 3 months - up to 5 mg - every 48 hours. Locally, for the treatment of skin areas damaged by pustules, tampons moistened with Miramistin solution were used, after drying in air - Terramycin-spray, followed by application of Akriderm Genta ointment. At the same time, protective bandages and special shoes were used constantly, until the paw pads were completely healed. Due to the regular occurrence of symptoms such as alopecia, depigmentation, the appearance of erythematous spots, etc., vitamin E (100 mg 1 time per day) was prescribed. As a result of this treatment, a stable remission was achieved within a year and a half. The dog is under supervision.

Bibliography:

1.Medvedev K.S. Diseases of the skin of dogs and cats. Kyiv: "VIMA", 1999. - 152 p.: ill.

2. Paterson S. Skin diseases of dogs. Per. from English. E. Osipova M.: "AQUARIUM LTD", 2000 - 176 p., ill.

3. Paterson S. Skin diseases of cats. Per. from English. E. Osipova M.: "AQUARIUM LTD", 2002 - 168 p., ill.

4. Roit A., Brostoff J., Mail D. Immunology. Per. from English. M.: Mir, 2000. - 592 p.

5 Bloom P.B. Diagnosis and treatment of autoimmune skin diseases in dogs and cats. [Electronic resource] - Access mode. - URL: http://webmvc.com/show/show.php?sec=23&art=16 (accessed 04/05/2015).

6.Dr. Peter Hill BVSc PhD DVD DipACVD DipECVD MRCVS MACVSc Veterinary Specialist Centre, North Ryde - Pemphigus foliaceus: review of clinical signs & diagnosis in dogs and cats [electronic article].

7. Jasmin P. Clinical Handbook of Canine Dermatology, 3d ed. VIRBAC S.A., 2011. - p. 175.

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11. Scott D.W., Miller W.H., Griffin C.E. Muller & Kirk's Small Animal Dermatology. 6th ed. Philadelphia: WB Saunders; 2001:667-779.

autoimmune disease - This is a violation of the activity of the immune system, in which an attack of the organs and tissues of one's own body begins. In other words, the immune system perceives its tissues as foreign elements and begins to damage them.

The immune system is a defense network of white blood cells, antibodies, and other components involved in fighting infection and rejecting foreign proteins. This system distinguishes "self" cells from "foreign" cells by markers located on the surface of each cell. That is why the body rejects transplanted skin flaps, organs and transfused blood. The immune system can malfunction, either due to the inability to do its job, or its overactive performance.

In autoimmune diseases, the immune system loses the ability to recognize "its" markers, so it begins to attack and reject the body's own tissues as foreign.

The mechanism of autoimmune processes is similar to the mechanism of immediate and delayed types of allergy and is reduced to the formation of autoantibodies, immune complexes and sensitized T-lymphocytes-killers.

The essence of autoimmune processes lies in the fact that under the influence of pathogens of infectious and parasitic diseases, chemicals, drugs, burns, ionizing radiation, feed toxins, the antigenic structure of organs and tissues of the body changes. The resulting autoantigens stimulate the synthesis of autoantibodies in the immune system and the formation of sensitized T-lymphocytes-killers capable of carrying out aggression against altered and normal organs, causing damage to the liver, kidneys, heart, brain, joints and other organs.

Autoimmune diseases are organ (encephalomyelitis, thyroiditis, diseases of the digestive system caused by chronic intoxication and metabolic disorders) and systemic (autoimmune diseases of the connective tissue, rheumatoid arthritis). They can be primary and secondary. Primary ones arise as a result of congenital and acquired disorders in the immune system, accompanied by a loss of tolerance of immunocompetent cells to their own antigens and the appearance of prohibited clones of lymphocytes.

A characteristic feature of autoimmune diseases is a long undulating course.

Diagnosis of autoimmune diseases is made on the basis of anamnestic data . Clinical manifestations of the disease, hematological, biochemical and special immunological studies for the detection of antigens, antibodies, antigen + antibody complexes and sensitized lymphocytes.

Autoimmune eye diseases in animals:

• or Chronic superficial vascular keratitis- this is a lesion of the limbus and the cornea of ​​​​the eye, resulting from a local chronic inflammatory process. The infiltrate formed under the corneal epithelium is replaced by scar tissue, which leads to a significant decrease in vision. The immune system considers its own cornea to be a foreign tissue and tries to reject it.

The first reports of pannus appeared in areas with high ultraviolet activity (in Austria and the US state of Colorado). To date, the disease is registered in all countries of the world. And it's no secret that cases of pannus in areas with increased ultraviolet activity are more difficult and less treatable. This allows us to conclude that ultraviolet rays play an important role in the occurrence of this disease. This phenomenon is due to the fact that exposure to ultraviolet radiation on the cornea accelerates the rate of metabolic processes in the latter. And the more active the metabolic processes, the more actively the immune system tries to reject it.

This pathology is most common in dogs of breeds such as German Shepherd, Black Terrier and Giant Schnauzer. It is much less common in dogs of other breeds.

• or Plasma lymphatic conjunctivitis of the third eyelid is a condition where a similar immune response affects the conjunctiva and the third eyelid. Plasmoma is less threatening to loss of vision, but delivers more ocular discomfort.

In dogs of the Akita Inu and Chow Chow breeds, a predisposition to this disease is noted. The causes leading to the development of the disease include idiopathic, as well as those associated with the use of drugs. Lesions spread to the muzzle and ears, fingers, abdomen near the nipples, and a generalization of the process can be observed when the lesions are spread over the entire surface of the body. Lesion progression begins with erythematous maculae, followed by pustules, epidermal collars, erosions, and yellow-brown crusts. Clinically, skin lesions may be accompanied by distal limb edema, fever, drowsiness, and lymphadenopathy. Differential diagnoses include pyoderma, dermatophytosis, demodicosis, zinc-dependent dermatosis, discoid lupus erythematosus, erythema multiforme, leishmaniasis, sebadenitis.

Establishing diagnosis

Among the possible side effects in dogs, anemia, leukopenia, thrombocytopenia, pancreatitis can form. In this regard, at the initial stage, every 14 days (for 2 months), then every 30 days (for 2 months) and, finally, every 3 months for the entire period of giving azathioprine, clinical and biochemical blood parameters in dogs should be monitored. In general, when it comes to monitoring the general health of patients treated for pemphigus, it should be remembered that every 6 months, all those who are given glucocorticoids require a routine examination. It includes a clinical and biochemical blood test, a clinical urinalysis and a urine culture for bacterial flora.
Features of therapy in cats is that if it is not possible to reduce the dose of prednisolone, then chlorambucil is introduced into the regimen. Dosing regimen, precautions and monitoring for chlorambucil therapy in cats are the same as for azathioprine in dogs. The initial dose of chlorambucil is 0.1-0.2 mg/kg daily.
Dogs not responding to azathioprine may also be treated with chlorambucil. Vitamin E at doses of 400-800 IU 2 times a day and essential fatty acids can be used as adjuvant therapy in dogs, as they have anti-inflammatory and antioxidant properties.
In dogs, a combination of tetracycline and niacinamide may be used because the combination has many anti-inflammatory and immunomodulatory properties. Which, in turn, allows the use of these drugs for the treatment of various immune-mediated skin diseases, such as discoid lupus erythematosus, lupus onychodystrophy, metatarsal fistula of German shepherds, aseptic panniculitis, vasculitis, dermatomyositis and others. Doses for dogs weighing less than 10 kg are 250 mg of each drug every 8 hours. And for dogs weighing more than 10 kg - 500 mg of both drugs every 8 hours. In the presence of a clinical effect, which can occur no earlier than after a few months, the drugs begin to be reduced - first to a double dose, and then to a single daily dose. Side effects are rare and are usually associated with the use of niacinamide. These include vomiting, anorexia, drowsiness, diarrhea, and elevated serum liver enzymes. Tetracycline may lower the seizure threshold in dogs.
In cats, doxycycline at a dose of 5 mg/kg 1-2 times a day can be used as an immunomodulator. After oral administration of doxycycline, cats must then be given at least 5 ml of water, as otherwise there is a high risk of esophageal stricture. In the absence of success from the proposed therapy with prednisolone (high doses are required) or if there is no success from its various combinations with other agents (antioxidants, immunomodulators), it is suggested to try switching to dexamethasone or triamcinolone as recommendations. The initial dose of drugs is 0.05-0.1 mg / kg 2 times a day, and then gradually reduced in the same way as in the case of prednisolone.
High-dose glucocorticoid pulse therapy is suggested as a last choice for intractable cases of exfoliative pemphigus. After such pulse therapy, upon reaching the effect, continue to give prednisolone at the recommended doses with a gradual decrease in the drug, as described above.

There are two pulse therapy protocols:

Clinical cases of exfoliative pemphigus in our practice

Case 1 On March 7, 2012, 1.5-year-old Labrador Martin was admitted to our clinic. From the anamnesis it followed that this animal is kept at home, in the summer it is in the country, there are no contacts with other animals, the owners did not have any skin problems. Akana food has been used as feeding for the last three weeks, before that, beef, rice, and buckwheat were present in the diet. There were no seasonal manifestations of Martin's skin disease. At the time of admission, the owners noted severe itching, which was localized in the head, limbs, sides, abdomen, and back of the animal. The damage started a few weeks ago. Antibiotics were used as therapy: ceftriaxone - 7 days; ciprofloxacin - 7 days; ceftazidime - 7 days; Convenia was used two days before admission. According to the owners, such a change of antibiotics was carried out by the attending physician due to the absence of any effect from antibiotic therapy.
Examination revealed multiple lesions, including pustules and mostly crusts on the patient's head, back, abdomen, flanks, and extremities (Figures 1-3).

As differential diagnoses, we considered skin infections (demodecosis, dermatophytosis, secondary pyoderma) and pemphigus foliaceus. The scrapings were negative. The cytology of the smear included single bacteria (which did not correspond much to a similar clinical picture in pyoderma), without neutrophilic phagocytosis. The neutrophils we found in this smear were non-degenerative. At the same time, a significant amount of acantholytic keratinocytes was determined.
A biopsy was suggested, sowing on dermatophytes (the owners refused to sow). As a temporary therapy, it was proposed to continue the trial antibiotic therapy, but to arrive at the appointment after the end of the effect of the convenia drug (cefovecin - a cephalosporin of the 3rd generation) to conduct preliminary crops in order to select an antibacterial drug. The owners agreed only to a biopsy, unfortunately, without accepting our other proposals, and returned to their doctor for further treatment. After some time, the owners of the animal asked for the results of histology, confirming one of our differential diagnoses - pemphigus foliaceus (Figure 1). They refused to discuss treatment regimens. We do not know about the further fate of this patient.

Case 2 On November 28, 2012, a 2-year-old Scottish Longhair cat named Tori was admitted to our clinic. From the anamnesis it followed that the animal lives in an apartment, the owners of the cat from an early age, the animal had no skin problems at the time of purchase. There was contact with a domestic cat 2 months prior to the onset of problems, and there were no skin problems in the pet that was in contact and there were no further problems. The owners have no skin problems. Hills dry cat food was used as food.
As complaints, the owners noted that a few months ago their animal had crusts on the ears, on the muzzle, on the stomach around the nipples. Of the general symptoms, some apathy and slight itching were noted at the sites of lesions on the skin. Antibiotics and corticosteroid hormones (prednisolone) were used as therapy. Against the background of the use of prednisolone, the picture improved somewhat. Twice there was some spontaneous improvement, which lasted for some time, and then the picture resumed.
When examining Tori, it was noted that as lesions at the time of admission, there were crusts on the ears, head, and nipples (photo 4-5). No pustules were found.
The following differential diagnoses were considered as bacterial inflammation of the skin, dermatophytosis, pemphigus (which, from our point of view, was the most likely differential diagnosis).

Research at the time of initial treatment:

• LUM - negative;
• Trichogram - no hair destroyed by dermatophytes;
• Scrapings - negative;
• Smears from under the crust: the result is the presence of acanthocytes (photo 6), neutrophils in large numbers; bacterial flora is absent.