Feline leukemia treatment drugs. Viral leukemia (leukemia) of cats - FeLV. What is leukemia

Hello Julia.

First of all, I want to wish you patience and perseverance in overcoming the difficulties that have arisen. Judging by your appeal, you love your pet very much and sincerely want to help him.

Stages of the disease

The situation is very difficult. I don't know what stage of the disease the animal is in. There are five main ones:

1. Penetration and rooting of the virus in the pharyngeal lymph nodes and tonsil cells;
2. The defeat of B-lymphocytes and macrophages, which begin to actively spread the virus throughout the body;
3. Penetration into the lymphoid tissue and damage to the cells of the epithelial layer of the intestine, the beginning of the penetration of the virus into the bone marrow;
4. The release of infected platelets from the bone marrow directly into the blood;
5. Infection of the epithelium and lymph nodes, the release of the virus into the urine and saliva of the animal.

If a cat, and viral leukemia is typical for cats (people and dogs are not susceptible to this disease), strong immunity, the virus after penetration into the body and development to stage 1 - 3, as a rule, slows down its "attack" for 4 - 6 weeks, and the disease passes into a latent (sluggish) state. This situation can continue for years, but at any time, as soon as the immune system fails, the disease can begin to progress again.

It is regrettable to state that 97% of affected cats remain carriers terrible virus until the end of his life. In sick cats, there is a strong depletion of the whole organism, lymph nodes hypertrophy, lymphosarcoma is formed ( malignant tumor). The survival rate is extremely low. But a fraction of hope remains! By at least, a cat can extend the life of several years.

Treatment

Russia has not yet created effective drugs that can defeat leukemia. talk about some therapeutic effect possible after use in a complex of immunomodulators (roferon solution, 30 units / day daily for a week, repeated after a week; additional immunoregulin intravenously at 0.5 ml no more than 2 times a week; carrisin 100 mg per day orally) and various cytotoxic drugs. Such treatment can only be prescribed by an experienced veterinarian.

There is an immunomodulator not certified in Russia by the French manufacturer Virbac - Virbagen Omega (WirbagenOmega) - feline omega-interferon. According to reviews, it well supports the immunity of infected animals. But the drug is not cheap, and it has to be ordered from abroad.

Since it can be very difficult to detect signs of the onset of the disease immediately after the virus enters (in most cases, they become apparent after months or even years), there are not so many ways to deal with it. If the animal has pronounced anemia, exhaustion, mental disorders, and also there are signs of secondary infection against the background of weakened immunity (diarrhea, painful urination), the cat is hospitalized. The patient begins to be additionally parenterally fed with nutrient mixtures and liquids; in emergency situations, a blood transfusion is prescribed from individuals who have been immunized for the virus.

Prevention

For the future, please keep in mind that a healthy animal can only be vaccinated after prior serological testing for the leukemia virus. Infection occurs through contact with sick individuals, through saliva, urine or feces of carriers of the virus. Most often, young animals up to 3 years of age get sick. Up to 80% of an infected cat's litter dies in utero or in the first 2 to 3 days of life.

Good luck and patience to you!

Sincerely, Alexander.

• Cats (as a result of behavior)
• free range
• Multiple cat population

Pathophysiology of feline viral leukemia

• Early pathogenesis feline viral leukemia, FeLV, FLV consists of 5 stages:

1. viral replication in the tonsils and pharyngeal lymphatic vessels;
2. infection of several circulating B-lymphocytes and macrophages spreading the virus;
3. replication in lymphoid tissues, intestinal epithelial crypts, and bone marrow progenitor cells; 4) release of infected neutrophils and platelets from the bone marrow into circulatory system;
4. infection of epithelial and glandular tissues, followed by the release of the virus with saliva and urine. An adequate immune response stops at stages 2 and 3 (4-8 weeks) after infection and is enhanced latently (hidden) by the virus. Persistent viremia (stages 4 and 5) usually develops 4-6 weeks after infection, but may take up to 12 weeks in some cats.
5. Tumor induction in FLV infection is manifested by the integration of provirus DNA with cat chromosomal DNA in critical DNA regions (“oncogenes”); VLC integration near the cellular gene in a certain area can cause the development of thymic lymphosarcoma. Changes in the FLV gene, also derived from mutation or recombination with an endogenous retroviral env sequence, additionally play a role in the genesis of neoplasms (tumor formation). In fact, feline sarcoma viruses mutate from FLV, which appears by recombination between FLV genes and host cells. As a result, host virus-binding proteins are responsible for the efficient induction of fibrosarcoma by these viruses.

What organ systems of a cat are affected by feline viral leukemia, FeLV, VLK

History of viral leukemia

Clinical Study Results

• Results depend on the type of disease (neoplastic or non-neoplastic) and the presence/absence of a secondary bacterial infection.
• Moderate to severe lymphadenopathy
• Signs from the upper respiratory tract in the form of rhinitis, conjunctivitis, keratitis.
• Persistent diarrhea - overgrowth of bacteria or fungi, parasitic inflammation, or direct effect of FLV on intestinal crypt cells
• Gingivitis/stomatitis/periodontitis
• Chronic, persistent or recurrent infections of the external auditory canal or skin.
• Fever and exhaustion
• Lymphoma (lymphosarcoma) in most cases of VLC, an associated neoplastic disease. Thymic and lymphocentric lymphomas are closely associated with FLV infection in cats; mixed lymphoma (of extranodal origin) most often involves the eyes and nervous system. Erythroid and myelomonocytic leukemia are the predominant forms of non-lymphoid leukemia. Fibrosarcoma develops in cats co-infected with FLV and a mutated sarcoma virus and occurs most frequently in young cats.
  • Immune complex diseases such as thrombocytopenia, immune-mediated hemolytic anemia, and glomerulonephritis
  • Thymic atrophy (kitten wilt syndrome)
  • Peripheral neuropathies

• Alimentary form: cats show anorexia, vomiting and diarrhea. Abdominal masses cover small intestine, blind and large intestine; the corresponding lymph nodes may also be affected.
• Multicentric form: generalized lymphadenopathy, renal lymphosarcoma, splenomegaly and hepatomegaly. This form is usually seen in young cats.
• Thymic form: dysphagia and dyspnea are the most common signs, with cyanosis in the most severely affected animals. The pleural effusion may contain neoplastic cells.
• Lymphoid leukemic form: The bone marrow is primarily involved and cancerous lymphocytes circulate in the blood. Jaundice, fever, and mucosal pallor are the most common findings, and lymphadenopathy, splenomegaly, and hepatomegaly may also be present. obvious varying degrees fever, anorexia and weakness.
• Myeloid leukemia is the main lesion in this non-lymphosarcoma form in the bone marrow, with secondary involvement of the liver, spleen, and lymph nodes. This form of leukemia is named according to the type of damaged cell from the hematological lineage, myelogenous leukemia, erythroleukemia, and lymphoblastic leukemia. Signs include progressive anemia, recurring fever, and weight loss. It must be remembered that not all cats with the above forms of FLV infection will be serologically positive for FLV antigen.

• Chronic recurring rhinitis or sinusitis, sores around the nails, and periodontal disease may be present. Be that as it may, all of these diseases can be a manifestation of feline immunodeficiency infection. cure infectious processes, including abscesses, can be difficult due to VLC involvement.
• FLV-infected cats are particularly susceptible to bacterial, fungal, and viral respiratory and intestinal infection. In chronic cases, it manifests itself with persistent fever and increased weight loss.
• VLC may predispose to infection viral peritonitis cats and feline hemobartonellosis (Haemobartonella felis) - infectious anemia of cats.
• A syndrome similar to panleukopenia accompanies with FLC infection. It occurs in cats vaccinated against panleukopenia and is fatal without exception.

• VLC can lead to the death of embryos and fetuses, their resorption, abortion and infertility. Fetal death can occur due to endometritis and placentitis. Approximately 75% of cats lead to abortion.
• Surviving kittens infected are weak and sickly. FLV infection is considered to be the cause of a pathology called Kitten Wilting Syndrome.

1. Muffled, decreased heart sounds
2. SNK time extension
3. Tachycardia, fast pulse
4. Weak, small pulse
5. Abdominal stretch
6. Anorexia
7. Ascites
8. Blood in feces
9. Mucosal thickening oral cavity, redness of the mouth
10. Decreased fecal volume, constipation
11. Diarrhea
12. Vomiting movements
13. Hepatosplenomegaly, splenomegaly, hepatomegaly
14. Melena
15. Ulcers, erosions, vesicles, plaques, pustules, wounds
16. Polyphagia
17. Vomiting, regurgitation
18. Abnormal proprioceptive positioning
19. Ataxia, discoordination, falling
20. Dehydration
21. Dysmetria, hypometria, hypermetria
22. Fever
23. Forefoot edema
24. Atrophy of the forelimb
25. Lameness of the forelimbs
26. Swelling of the forelimb
27. Weakness of the forelimb
28. Generalized lameness
29. Generalized weakness, paresis, paralysis
30. Bleeding in any part of the body, increased clotting time
31. Swelling of the head and neck area
32. Edema, swelling of the back foot
33. Atrophy hind limb
34. Lameness of the hind limb
35. Edema, swelling of the hind limb in any area
36. Hypothermia
37. Jaundice
38. Inability to stand, prostration
39. Internal masses in the abdomen
40. intraocular masses
41. Lymphodenopathy
42. Swelling, swelling in the orbit, periorbital, conjunctiva, eyeball
43. Paleness of mucous membranes, skin
44. Paraparesis, weakness, paralysis of both forelimbs
45. Petechiae and ecchymosis
46. Polydipsia
47. Refusal to move
48. Rigidity and elongation of the neck
49. Subcutaneous swelling, masses, nodes in the neck
50. Weakness of the tail, paresis, paralysis of the sacrococcygeal region
51. Tenesmus, dyschezia
52. Tetraparesis, weakness, paralysis of all four limbs
53. Lack of weight, poor nutrition
54. Weight loss
55. Abnormal anal, perianal reflexes, increased or decreased
56. Abnormal forelimb reflexes, increased or decreased
57. Abnormal hindlimb reflexes, increased or decreased
58. Abnormal pannicular reflex, increased or decreased
59. circling
60. Coma, stupor
61. Constant or increased vocalization
62. Stupidity, weakness, lethargy
63. Hypoesthesia, anesthesia of the head, neck, tongue
64. Hyperesthesia, agitation, hyperactivity
65. Muscular hypertension, myotonia
66. Convulsions or fainting, convulsions, seizures, collapse
67. Abnormal pigmentation, iris color
68. Abnormal pupil shape, iris defect
69. Abnormal retinal reflectivity
70. Abnormal size of retinal vessels
71. Anisocoria
72. Blindness
73. Buphthalmia
74. Cataract
75. Corneal edema, opacity
76. Corneal neovascularization, pannus
77. Puffiness, knots, corneal masses
78. Ulcers, corneal erosions
79. enophthalmos
80. exophthalmos
81. Hyphema, blood in the anterior chamber of the eye, "black eye"
82. Hypopion
83. Miosis, meiosis, pupil contraction
84. Mydriasis, pupil dilation
85. nystagmus
86. Opacification or precipitation of the vitreous
87. Fallout of the third century
88. Retinal detachment
89. Strabismus
90. Synechia
91. back pain
92. Neck, neck, throat pain
93. Pain with external pressure on the abdomen
94. Abortion or neonatal weakness, stillbirth
95. female infertility
96. Dirty vaginal discharge
97. Purulent or mucous discharge from the vagina
98. Abnormal breath odor
99. Abnormal breath sounds
100. Cough
101. Muffled lung sounds, their absence
102. Dyspnea
103. epistaxis, nose bleed
104. Tachypnea
105. cold skin, ears, limbs
106. Skin inflammation, redness
107. skin fistula
108. Skin necrosis
109. Ulcers, erosions, skin excoriation
110. Hematuria
111. Renomegaly, enlarged kidneys
112. Polyuria
113. Proteinuria
114. Red or brown urine
115. Urinary incontinence

Differential diagnosis of feline viral leukemia

1. Feline Immunodeficiency Virus
2. Bacterial, parasitic, viral or fungal infection
3. Non-viral neoplastic process

Diagnosis of feline viral leukemia, FeLV, VLK

• Exclude diseases listed in the differential diagnosis.
• If VLC is suspected, a large number of diagnostic procedures to confirm the diagnosis, including histopathological examination of biopsy specimens, bone marrow analysis, cytology of chest and abdominal cavity. However, the most practical way to diagnose VLC is by ELISA and ELISA, discussed below.
• Blood drop ELISA and serum ELISA are the methods most commonly used to detect antigen (mainly the p27 capsid protein). This antigen can be found in large quantities in the cytoplasm of infected leukocytes and platelets. Soluble Form found in plasma and serum of infected cats. For ELISA, a study on extreme meri three blood samples. A positive test indicates the presence of the virus.
• The results of ELISA and ELISA tests are almost identical.
• 80% of cats with the virus die within 3 years.
• Commercial ELISA and ELISA kits have been developed and are available, as well as kits for diagnosing FLC in kittens.
• The virus can be isolated in cell culture, but this is time consuming and costly.
• PCR can detect the presence of the virus, but this method research is not always available.

• Unfortunately, there is no guarantee that certain diagnostic tests will fail when either a false positive or a false negative result can be obtained. Therefore, any diagnostic test must be interpreted in light of the results of other diagnostic tests.
• In general, a negative test indicates the absence of detectable viral particles in the bloodstream for the duration of the test. There is no guarantee that you will not get this disease some time in the future. A positive test should be checked specifically in cats without pathological signs this disease. VLV vaccination does not result in a positive test result.
• FLC test ELISA (enzyme binding immunosorbent assay). Very accurate. And checks for the presence of the virus in blood, saliva or wounds. Most of the experimental cats tested positive by day 28 post-infection, although some may take much longer. Test-positive cats must be tested within 30 days, as some of them may show a negative result. It also controls the presence of antibodies against the feline immunodeficiency virus. This is an additional benefit as it requires less blood when using a combined test than when running 2 different tests. In addition, the diagnosis is very accurate and requires no more than 15-20 minutes of time.

• Serology for the determination of VLC antigen, p27. ELISA is available in diagnostic laboratories, it determines p27 in leukocytes and platelets, a positive result indicates a productive stage of FLV infection in bone marrow cells. The majority (97%) of ELISA-positive cats remained permanently infected for life. P27 antigen can be detected by ELISA as early as 4 weeks after infection, but in some cats a positive test does not appear until 12 weeks later.
• ELISA test for the determination of soluble p27 FLV antigen in whole blood, serum, plasma, saliva, or tears is more sensitive than ELISA for early short-term VLC infection; but the only one positive test does not mean that the cat will definitely be infected. A repeat ELISA test is recommended at 12 weeks, and many veterinarians in parallel, ELISA diagnostics is carried out at this moment. False-positive ELISA tests occur more frequently with whole blood than with serum or plasma, or with saliva and tear tests; cats that test positive should be retested using whole blood (ELISA) or serum (ELISA).

Patient Monitoring

Prevention of feline viral leukemia

Prognosis for viral leukemia

Treatment of cats with viral leukemia

• Biopsy or removal of tumors
• Oral cavity treatment and surgery (teeth cleaning, tooth extraction, gingival biopsy)

• Control of secondary opportunistic infections and supportive care such as parenteral fluids and nutritional support may be needed in some cats.
• Immunomodulatory therapy may alleviate some clinical disorders. Human recombinant interferon alpha can increase lifespan and improve clinical status. Additional immunomodulatory drugs include Propionibacterium acnes and acemannan.
• Hemobartonella infection should be suspected in cats with non-regenerative hemolytic anemia, treatment consists of 3 weeks of oxytetracycline with a short course of oral glucocorticoids in severe cases.
• Blood transfusion can provide emergency support; multiple transfusions may be required. Passive administration of antibodies may reduce the level of VLC-antigenemia in some cats; thus, immunization with FLV vaccine in donor cats is very beneficial.
• Lymphosarcoma in FLV-positive cats can be successfully controlled with combination chemotherapy. The regimen includes vincristine, cyclophosphamide, prednisone as the most widely used. On average, remission periods are 3-4 months, but in some cats this period can last much longer. Myeloproliferative disease and leukemia are the most refractory (resistant) to treatment.

Feline leukemia is one of three chronic viral infections characterized by oncogenicity (development of lymphosarcomas), progressive anemia, and immunosuppression (decreased immunity).

The causative agent of the infection is an RNA-containing virus belonging to the family of retroviruses, subfamily of oncornaviruses, genus of oncoviruses. The virus was first isolated in 1964 at the University of Glasgow by the British scientist W. Jarrett, who, after conducting a series of studies, proved a direct link between the formation of malignant lymphomas and the presence of an oncogenic leukemia virus in felines. Three types of FLV (feline leukemia virus) are known: A, B and C. FLV-A is the cause of long-term developing lymphoma, FLV-C, affecting young dividing red bone marrow cells, in combination with FLV-A causes progressive anemia. In the external environment, the virus retains its properties for 2 days, heating to 70 degrees Celsius inactivates the virus for half an hour, VLK is resistant to ultraviolet radiation.

epizootology

The feline leukemia virus is widespread throughout the world, with the highest density of virus prevalence in regions with big amount stray cats or places with crowded animal housing (animal shelters and hotels that do not comply with sanitary standards), which facilitates their numerous contacts. Latent (hidden) virus carriage is widespread. Cats of all ages and breeds get sick, but humans and dogs are not affected by this virus. It can be excreted in saliva, milk, urine and faeces. Most frequent ways transmission of infection are the infection of offspring from the mother, as well as sexual contact during mating of animals.

Pathogenesis

The virus is released only by infected cells in the stage of mitosis (division). This explains the tropism (direction) of VLC - it multiplies in young rapidly dividing cells (red bone marrow, epithelium of the respiratory and digestive tract). After entering the body (by oral or aerogenic route), the virus replicates in the posterior pharyngeal lymph nodes, from which it then enters others lymphoid tissues and further to the red bone marrow. If a cat has a strong immune system, then after the virus enters its body, a rapid immune response occurs, after which the FLV is eliminated (destroyed). The virus can persist for a long time latent form in the bone marrow. For stress, prolonged surgical operations when the animal is in a state of anesthesia for a long time, or the introduction of immunosuppressants (corticosteroids, cyclosporins), intensive replication of the virus in the bone marrow can occur, and the latent (latent) infection passes into the phase of viremia (virus in blood cells), which can also be temporary, if the body is able to give an effective immune response. In the bone marrow, the virus is able to infect stem cells of the myeloid, erythroid, and lymphoid lines. This stage lasts 2 to 4 weeks after the initial infection. Stem cells affected by the leukemia virus are produced into infected blood cells, which leads to viremia and the classic clinical picture of FLC: the formation of lymphomas, progressive anemia, general weakness, unsteady gait. The most common lymphomas are in the intestines, where ultrasound detects local thickening of the walls of the intestine or stomach, as well as a significant increase in the size of the mesenteric (intestinal) lymph nodes.

Clinical picture

Feline viral leukemia is quite difficult to diagnose, since at the initial stage the clinical picture can be identical to most gastrointestinal infections: weight loss, lethargy, lack of appetite, anemia. With the development of lymphomas, the symptoms of leukemia in cats become more diverse: with intestinal damage, vomiting, diarrhea, nodules visible on ultrasound as local thickening of intestinal loops, with eye damage, uveitis and glaucoma, with lung lymphoma, chylothorax (accumulation of lymph in chest cavity), with damage to the spinal cord, neurological symptoms occur, manifested first by unsteadiness of gait, and then leading in some cases to paralysis of the pelvic limbs.

Immunosuppression (decreased immunity) can provoke the development comorbidities: infectious peritonitis of cats, if the animal is a carrier of coronavirus, immunodeficiency of cats, as well as toxoplasmosis.

With transplacental (through the placenta from mother to fetus) transmission, offspring die in utero (in the uterus), or during the first days after birth due to progressive viremia.

Diagnostics

1. PCR (polymerase chain reaction)-diagnosis by peripheral blood. With viremia, VLC is confirmed (antigen detection), with latent carriage, the result is usually negative.

2. Linked immunosorbent assay(ELISA) - the identification of not the pathogen itself, but the products of its vital activity (markers).

3. A clinical blood test reveals severe anemia, leukocyte "shift to the right", a significant increase in ESR.

4. False-negative results for PCR and ELISA are not uncommon, therefore, repeated studies are carried out if the clinical picture corresponds to the disease. Negative VLK is considered after two negative samples blood for PCR (ELISA) with an interval of 12 weeks.

5. Visual diagnostics (ultrasound, radiography), which allows to detect lymphomas in the intestines, lungs or mediastinum. According to the results of visual diagnostics, additional, more precise research: gastro- and colonoscopy, laparoscopy followed by tissue biopsy from the affected area.

Treatment

Treatment of leukemia in cats is reduced to the so-called symptomatic therapy aimed at eliminating the consequences of the cytopathic (damage to young cells) of the virus. Unfortunately, there are no drugs that can completely destroy VLK. Choice antibacterial drug(penicillins, cephalosporins, quinolones), depends on localization pathological process. Classical immunomodulators (Ronko- and Betaleukin, Gala-vet and others), as well as hemopoiesis stimulants (epocrine, erythrostim) are not used in the treatment of cats diagnosed with VLC due to the tropism of the virus (a tendency to infect young dividing cells). Immunosuppressors (prednisolone) are used in complex therapy at a certain stage and only under the supervision of the attending physician.

Of the immunomodulators used in the treatment of VLC, as in any other chronic viral infection of cats, one can distinguish Virbagen Omega (WirbagenOmega) from the French company Virbac, a feline omega-interferon that increases the cellular immunity of animals. This drug in Russia it is not certified and when ordering it from abroad it is very expensive.

Chemotherapy is used in the treatment of lymphomas in veterinary medicine, and with proper treatment, the size of the tumor decreases, but, as a rule, periods of remission (rest) are not long, and repeated courses of treatment are necessary after a few months.

Prevention

Vaccination is the best way to protect your cat from FLV. In Russia, the most common vaccine is Leukocel (Pfizer), which contains an inactivated (killed) feline leukemia virus (types A, B, and C), which induces a reliable immune defense 3 weeks after vaccination, which lasts for 1 year. The French vaccine Purevax FeLV (Merial) has similar properties.

In addition, it is also recommended to periodically wash at high temperatures bedding of animals, as well as thoroughly washing hands and protecting shoes from access after contact with other cats to prevent infection of their pets.

Leukemia is one of the incurable pathologies that differs rapid development. To date, for the treatment of this disease, drugs are used to prolong the patient's life for many years.

Life expectancy will depend on the state of the general organism and the type of disease. The most difficult to stop is viral leukemia, which quickly leads to tissue damage and attachment various complications that worsen the overall clinical picture.

Viral leukemia is a disease caused by the ingestion of oncogenic RNA genomic retrovirus type C. It belongs to the Retrovindae family of oncorn viruses, genus Oncovirus. This antigen has the property of reverse transcriptase, due to which the DNA genome of the provirus is formed. As a result of the changes, DNA begins to produce RNA on its own.

Statistics

To date, of the total number of patients with leukemia, 15% of patients have its viral form. This pathology is inherent in geography. The majority of people infected with RNA are in Okinawa and Japan.

In these territories today there are already more than 1 million people affected by viral leukemia. Of these, only 46% developed antibodies to pathological cells. On the territory of non-endemic areas, no more than 500 cases of infection are recorded per year, where the majority are adults.

Possibility of infection

Medical scientists have noted that almost half of the people infected with RNA did not have any pathology or deviations in health. To find out the cause of this phenomenon, the mechanism of the introduction of the virus into the human body was studied in detail.

After entering the body, does not directly affect healthy cells, and therefore may not be perceived as an atypical body. As a result, it is not always possible to obtain a protective response of the organism and RNA integrates into DNA without problems.

A delayed immune response is excluded due to the fact that the virus is introduced into DNA, repeating the turns and properties of transposons. Mutated DNA integrates into the cell genome, which subsequently begins to produce new infected cells.

In the case of a more sensitive immune system, the virus is recognized already at the stage of introduction into the DNA, for which antibodies begin to be actively produced. total mass antibodies not enough to completely eliminate the antigen.

It is also implanted in DNA, but already immunity prevents it from infecting the body. Such people do not become infected themselves, but being active carriers of the infection, can infect others. Only in 1% of carriers after 10 years or more, the virus can still cause leukemia.

After long-term observations, it was found that a certain group of people is most susceptible to infection:

• who have had diseases, provoking immunodeficiency states;
• living in areas with a high level of infection;
• leading promiscuous sex life.

Ways of infection

The virus that provokes the development of leukemia is not stable in the external environment, and therefore cannot be spread by airborne droplets.

This pathology is characterized by infection through direct contact with biological fluids a person, therefore, the main route of infection is considered:

1. Breast-feeding. The child does not have strong immunity capable of destroying the RNA that enters his body with mother's milk. The probability of infection in this case is very small, since all viruses die in the stomach. But infection is allowed in the presence of wounds or irritations that open a direct path for pathological cells into the circulatory system.
2. Sexual contact with a carrier of the infection. Most often, infection of women is observed, which is explained by the rejection of the ejaculate, which contains the maximum number of infected lymphocytes.
3. Transfusion or blood sampling. The main part of leukemias, the cause of which was infection through the blood, was provoked by an injection made with a single syringe. This phenomenon is most typical for drug addicts. In isolated cases, there are situations when infection occurred through a transfusion of infected blood.

sick animal

In some sources, as a route of infection, indicate products from sick animals. For example, through milk, meat, eggs. But to date, this theory has not received any scientific justification, even after detailed and repeated cytological and histological studies.

The only thing that was revealed during these studies was the release of carcinogens into the blood, which can cause disruptions in the functioning of some body systems.

Symptoms

Except common symptoms of all cancers, which are manifested by general weakness with temperature and malaise, there are a certain number of signs that are characteristic only of viral leukemia:

• appearance related frequent infections , which is associated with a general weakening of the immune system;
• severe hypercalcemia. To date, the mechanism of its development in this pathology has not been studied;
• infiltration skin and the appearance of an itchy rash on it. It acts as a complication as a result of a skin infection with a virus;
• changes in the color of the mucosa. Active development leukemia leads to a complete disruption of trophic processes;
• muscle weakness. Violation of normal metabolism leads to leaching of microelements and soft tissues, while muscle weakness is aggravated by numbness of the extremities;
• shortness of breath, shortness of breath. Occurs when the respiratory system is affected;
• entrainment of lymph nodes. Acts as defensive reaction organism to a foreign cell.

The mechanism of the development of the disease

Since the last moment of introduction into DNA and mutation of primary stem cells, takes about 2 months. Throughout this period in the bone marrow occurs accumulation pathological cells that stop production of normal blood cells and replace them.

Spreading throughout the body viral cells lead to damage to the lymphatic system. Then amazed spleen and liver which increase in size. The last and most severe stage in the development of leukemia is decline to the maximum minimum level, quantity platelets in the blood.

Diagnostics

For accurate diagnosis diseases will use two main methods:

ELISA. It is a study based on the detection of atypical antibodies using certain biochemical reactions. This method allows you to detect immunoglobulin, which is produced by the defense system for the introduction of the antigen. Blood is used for analysis cerebrospinal fluid, the collection of which is carried out only on an empty stomach.

If, as a result of the analysis, positive reaction all titers, then the pathology is present in active form. If the value of all indicators is negative, then infection has not occurred.

The situation when part of the credits has positive value, and part is negative, indicates a strong immunity to the introduced virus.

PCR. On this moment, this method is the most accurate in diagnosing leukemia. Virus detection is carried out by partially increasing some DNA fragments. For analysis, a blood sample is taken, which is taken on an empty stomach.

Results in this case can be easily deciphered. A positive result proves the presence of the antigen in active form. A negative result confirms the absence of infection.

Forecast

In the treatment of viral leukemia at least 71% live 1 year. The number of patients surviving over 5 years is only 66%. Of this number, 1/3 more men survive than women. The ten-year term shows that the number of survivors is 44% for women and 49% for men. At the same time, the bulk of the deaths are at the age of 40 years and older.

More information about the disease can be found in this video:

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Our smaller brothers need close attention and constant care of the owner, because they are prone to many dangerous ailments. Cancer diseases, which often lead to the painful death of the animal, did not bypass them. Leukemia is one of the most common and devastating cancers in cats.

What is leukemia

Interested in how to deal with it? serious illness, it is necessary first of all to understand what it is and what is the danger of this disease. Leukemia, or leukemia, is a viral disease in which there is an occurrence in the bloodstream a large number young immature leukocytes. The causative agent of the disease is considered to be an RNA virus, which belongs to the genus of oncoviruses from the family of retroviruses.

With leukemia, a cat's immunity decreases, internal organs are affected.

Leukemia occurs in a chronic form and is characterized by a significant weakening of the immune system, pathologies of the kidneys and liver, anemia, peritonitis and ascites, as well as damage to the mammary glands in females.

Unfortunately, leukemia affects all cats, regardless of age category, breed and physiological state. Kittens and young individuals are most sensitive to the RNA virus. There are cases when acute course cat diseases die in just 3-4 years.

Ways of transmission of the disease and more about the pathogen

RNA virus is an oncogenic virus that has carcinogenic properties and can cause cancer. The hereditary material of a domestic cat contains about 100 varieties of copies of endogenous (internal) viruses. Scientists believe that under the influence of certain factors, these viruses begin to spontaneously be produced in the cat's body, which leads to the development of chronic leukemia.

But this happens very rarely. In most cases, the causative agent of the disease are exogenous (external) viruses circulating in the environment. These viruses were discovered back in 1964, at the same time it was revealed that leukemia in cats is indeed viral in nature and affects all members of the cat family without exception. Scientists have also found that the virus first enters the bloodstream, and then sent to the red bone marrow.

The photo shows the causative agent of feline leukemia.

Interesting. The uniqueness of the RNA virus lies in its ability to mix with other pathogens, such as the mouse sarcoma virus. As a result, the resulting hybrid has a detrimental effect on the cells of the cat macrophage system, but does not affect the mouse body in any way, even with targeted infection.

Notably, not all cats exposed to the virus will become permanently infected. The immunity of 60% of infected animals will be able to destroy or inactivate the devastating virus, about 30% of cats will become chronically infected, and in 10% the virus is inactivated in some part of the body. It is the latter group that is susceptible to reactivation of the virus after suffering stress, illness, or under the influence of certain medications.

In cats incubation period between infection and the appearance of symptoms lasts a long time. During this period, the animals look healthy, but despite this, they shed the virus and can serve as a source of infection for other cats.

Leukemia is contagious to other cats and can be transmitted in several ways:

• through grass, ponds, foliage of trees on which the virus lives;
• through contact with an infected cat, since the virus is shed from the mouth along with saliva, as well as through urine, feces and tears;
• through blood-sucking insects that have drunk the blood of an infected animal;
• when viruses pass from the body of an infected mother to the embryo;
• during feeding, when the virus is transmitted with mother's milk to kittens.

The leukemia virus lives on plants through which it can be transmitted to cats.

Forms and symptoms of leukemia in cats

Based on the state of the cat's immune system, the amount of the virus introduced into the body, as well as the place of its concentration, several forms of leukemia can be distinguished:

• Persistent. The weakened immunity of the animal is not able to overcome the virus, as a result of which the cat gradually loses strength, and the disease progresses rapidly and eventually leads to death.
• Transient. Defense Forces organisms can fight the virus and defeat it. After getting the infection for three months, it remains active in the urine and saliva of the cat, after which it disappears, and the animal restores immunity and recovers.
• Latent. The virus is localized in the bone marrow, lymph nodes, liver and spleen. Its impact negatively affects the health of the cat: it begins to get sick more often, becomes lethargic and inactive, loses its appetite. A tumor forms in the tissues and blood circulation is disturbed.

The incubation period can take quite for a long time- from a couple of months to 6 years.

On initial stage diseases in the blood increases the number of leukocytes and lymphocytes. At the advanced stage, there is fatigue animal, severe malnutrition, loss of appetite, malfunction digestive system(constipation, vomiting), fever, depression and irritability and a specific cough. The lymph nodes, the liver and spleen grow in size, and seals can be felt in places where the virus is concentrated. The cat's eyes become bulging.

With leukemia, the cat's condition deteriorates rapidly.

other symptoms serve:

• trembling limbs, wobbly gait, partial paralysis;
• discharge from the eyes and nasal passages, frequent sneezing;
• arrhythmia or tachycardia;
• peritonitis;
• cyanosis;
• breast carcinoma;
• intrauterine fetal death early dates, as well as high mortality of newborn kittens.

Important. The long course of the disease can cause glomerulonephritis as a result of the deposition of the waste products of the virus in the kidneys.

How is the disease diagnosed?

Diagnosis of leukemia in cats is carried out using laboratory research. Modern veterinary medicine includes a whole range of methods that allow you to identify the disease even at the earliest possible date.

The most common include:

• ELISA (enzymatic immunoassay);
• biochemical blood test;
• general blood analysis;
• biopsy and histological examination of pathological material;
• polymerase chain reaction (PCR).

In addition to these methods, it is often used ultrasound diagnostics organs and radiography, making it possible to see lymphatic neoplasms in the organs. In some cases, laparoscopy, gastroscopy, colonoscopy or biopsy with further histological examination of the pathological material may be necessary.

There are also special tests to determine the disease. Most veterinarians recommend using primary diagnosis feline leukemia ELISA test. It detects the antigen of the virus in the blood, and to confirm a positive result, it is necessary to conduct an ELISA and PCR. The sensitivity of the test to the antigen reaches 98%.

To diagnose leukemia, veterinarians use a special test.

Treatment of leukemia virus in cats

Owners of affected cats serious illness like leukemia, they are tormented by the question of whether it is treated or not. After diagnosing viral leukemia, the doctor immediately begins the process of long and serious therapy.

To improve the well-being of the animal, antibiotics and drugs that normalize the state of the immune system are primarily prescribed. IN advanced cases may require hospitalization with further observation in a hospital setting. Veterinarians administer chemotherapy and blood transfusions. In such situations, immunosuppressive drugs are not used, since they negatively affect the formation of new cells.

It is not possible to completely get rid of the virus, because miracle cure has not yet been found from him. All therapeutic actions, carried out by a veterinarian, are aimed only at maintaining the body, strengthening immunity and weakening the disease. This will help extend the life of your beloved pet for several years.

To prevent leukemia, the animal should be vaccinated on time. The most popular vaccine today is Russian drug Leukocel, which begins to act after 21 days and remains active throughout the year.

Preventive actions

All cat inventory should be cleaned regularly.

Vaccination is considered the best way to protect your pet from viral leukemia, but do not neglect other useful tips:

• to protect the animal from contact with infected and not tested for leukemia cats, including not letting the animal go outside;
• observe cat hygiene: wash cat litter and clothes in time, clean the tray and clean the dishes;
• add vitamins to the diet of the animal;
• to not allow colds and hypothermia;
• visit the veterinarian in a timely manner and treat all diseases.

Is leukemia in cats transmitted to humans?

Only cats are susceptible to feline viral leukemia; the virus does not pose a threat to other pets and humans. There is no need to isolate a sick animal, except for the joint keeping of several cats.

Is leukemia contagious for dogs? Dogs also have this cancer, the causative agent of which is an RNA-containing oncogenic virus. Canine leukemia virus has morphological similarities with the causative agents of leukemia in cats, but has significant differences in antigenic structure. Therefore, feline leukemia cannot be transmitted to a dog.