Feline Retroviral Diseases Flashcards
What are the 2 major Retroviruses that affect cats?
- feline leukemia virus (gamma)
- feline immunodeficiency virus
What are the FeLV proteins that are found on its core and envelope?
CORE = p27 - produced by infected cells and detected by FeLV antigen tests
ENVELOPE = gp70 - responsible for attachment to infect cells, neutralizing Ab produced against it
What signalment is most commonly affected by FeLV? What are the 2 modes of transmission?
young, outdoor kittens in large populations
- high amounts in plasma - close contact, bite, mutual grooming
- vertical - in utero, nursing
(short survival in the environment)
What are the 5 steps to the pathogenesis of FeLV?
- oronasal exposure
- viral replication in local lymphoid tissue
- lymphocytes infected, circulate, and cause low-level viremia
- systemic infection of lymphoid tissue = LNs, spleen
- bone marrow infection = persistent high-level viremia affecting granulocytes and platelets
What are the 3 possible outcomes of FeLV infection?
- progressive infection = permanent, systemic infection and viremia, high risk of clinical disease, FeLV test positive
- abortive infection (regressor) = virus never spreads beyond local lymphoid tissue, no viremia
- regressive infection (transient, latent) = no persistent viremia, viral DNA incorporated into genome of infected cells
FeLV:
What is prognosis of FeLV like?
- 80% die within 3 years, will most likely develop disease
- survival time can possibly be extended with supportive care
What is the most common disease related to FeLV? What does it make these cates predisposed to?
potent immunosuppression
- recurrent infections
- FIP, FIV
- hemotropic mycoplasma
- chronic stomatitis and rhinitis
What is the most common hematologic disorder seen with FeLV? What is this a result of?
nonregenerative anemia - red cell aplasia due to a lack of early erythroid precursors = MACROCYTOSIS
infection of bone marrow elements
What 6 other hematologic disorders can be seen with FerLV?
- aplastic anemia - pancytopenia due to a lack of production of all cell lines
- hemolytic anemia
- anemia of chronic disease
- myelophthisis - normal marrow space is infiltrated and replaced by nonhematopoietic or abnormal cells
- thrombocytopenia
- neutropenia
What 2 things is hemolytic anemia due to FeLV associated with?
- immune-mediated
- Mycoplasma haemofelis infection due to immunosuppression
How can patients with FeLV develop neoplasia? What neoplasias are associated?
recombination of FeLV-A with a cellular oncogene forms and recombinant virus
- FeLV-B or feline sarcoma virus
- lymphoma
- fibrosarcoma
- leukemia
What are the 2 most common neoplasias associated with FeLV? Why does it make diagnosis difficult?
lymphoma and leukemia
cats with lymphoma will likely test negative on FeLV antigen tests
- high prevalence of viremia in mediastinal lymphoma
- low prevalence of viremia in alimentary lymphoma
What immune-mediated, reproductive, and neurologic diseases are associated with FeLV infection?
IMMUNE - glomerulonephritis, polyarthritis, uveitis
REPRO - infertility, fetal absorption
NEURO - spastic pupil syndrome, urinary incontinence, paresis
What 4 miscellaneous syndromes are associated with FeLV infection?
- enteritis
- hepatopathy
- Fading Kitten Syndrome - newborn kittens fail to thrive and are likely to expire prematurely, usually prior to weaning
- osteochondromatosis
How is FeLV diagnosed? How does it compare to other methods?
SNAP ELISA detects p27 soluble antigen not seen in cells
very sensitive and specific —> more sensitive than IFA