Infectious Disease And Immunology Flashcards
Which species act as the largest reservoir of Bartonella?
Cats
Which arthropod serves as an intermediate host for bartonella?
Fleas
Why is it difficult to attribute bartonella as the causative agent of clinical signs?
Large reservoir in cats, therefore positive pcr or serology could indicate exposure instead of causative agent. Can be subclinical infection.
Which mammal serves as the largest reservoir for borrelia?
Rats
Which arthropods serve as the intermediate host for borrelia?
Ticks
How long do ticks require to feed for borrelia to transmit to the new host?
48hrs
Where is borrelia likely to migrate to after initial infection of a host?
Connective tissues, more specifically synovial
What clinical signs would you expect if a patient was infected with borrelia?
Polyarthritis, or signs of a nephropathy (lab and golden retrievers more likely to have kidney signs)
What does the SNAP 4Dx test for that is sensitive to borrelia infection, rather than exposure?
It highlights if there is an antibody for the C6 peptide, which is specific to infection rather than exposure
How is mycobacterium lepraemurium and mycobacteria leprae likely to affect different signalments?
Both affect felines and cause feline leprosy. Leprae is more likely to affect cats >9yrs of age, lepraemurium affects cats <5yrs of age
How does mycobacterium based diseases typically present?
Granulomas, either in the lungs or disseminated. Disseminated more likely in immunocompromised animals.
What makes errlichia canis difficult to treat?
Intracellular parasite that resides within immune cells (granulocytes and monocytes)
How might you improve the sensitivity of blood smear analysis in the detection of errlichia canis?
Could take an auricular capillary blood sample as more likely to have cells with intracellular bacteria wedged peripherally.
Which type of infectious agents infect erythrocytes?
Mycoplasmal
Which is the arthropod acts as the intermediate host for mycoplasmal diseases?
Fleas
Which signalment of cat is more likely to contract mycoplasmal diseases?
Male, outdoor cats. Concurrent infection with FeLV and/or FIV predisposing factor.
What clinical signs would you expect from a patient in the acute phase of errlichia canis infection?
Thrombocytopenia, vomiting, anorexia, pyrexia
Why is it difficult to treat infections of brucellosis?
Bacteria resides within immune cells
How long do females shed brucellosis after an abortion ?
4-6 weeks
How long does it take brucellosis to migrate to the blood and make a patient bacturaemic with brucellosis?
3 weeks
Which signalment of dog has been found to be the largest reservoir of brucellosis ?
Males, resides in epidiymis and prostate
Which bacteria is the causative agent of plague infection?
Yersinia pestis
Which mammal are the reservoir species for yersinia pestis?
Rats
When is topical treatment for MRSA indicated?
When there is a superficial wound without systemic involvement. If there is systemic involvement, then concurrent IV antibiotics are indicated (vancomycin).
What is the incubation period for leptospirosis ?
7-10 days
Why would a patient be started on amoxicillin for leptospirosis infection, and moved to doxycycline?
Amoxicillin clears systemic infection, doxycycline used to clear renal tubule burden of spirochetes
What is the incubation period for histoplasmosis infection ?
12-16days
Where is coccidioidomycosis more likely to be contracted, geographically?
West Mexico, south west US, central and southern America
Where is blastomycosis more prevalent, geographically?
Ohio, Mississippi River valleys, southern Great Lakes, mid Atlantic states
What might you expect to see on radiographs of a patient with end stage blastomycosis?
Diffuse nodules, potentially with lymphadenomegaly of mediastinal lymph nodes
What do aspergillosis and cryptococcosis infection have in common?
Both fungal infections that colonise the nose, and have the potential to become more systemic.
How might cryptococcus be implicated in CNS signs?
Can infect the nose and the breach the cribriform plate to infect the brain
What is canine herpesvirus infection in neonates more colloquially called?
Fading puppy syndrome
At what age might a puppy be able to survive an infection with canine herpes. What long terms affects will puppies have if they survive?
Over 3 weeks. Long term affects however eg blindness, ataxia, chronic kidney disease
How is feline herpes virus spread between cats?
Direct contact with oronasal or conjunctival secretions of an infected cat actively shedding the virus.
What is the difference between cell mediated immunity and humoral immunity?
Cell mediated related to the destruction of cells with intracellular pathogens, mediated by T lymphocytes. Humoral immunity relates to the coordinated activity on extracellular pathogens, mediated by B lymphocytes.
What are the three ideal characteristics of an immunotherapy to treat cancer?
- High specificity (able to distinguish self and diseased cells)
- High sensitivity (able to destroy small or large numbers of malignant cells)
- Durability (able to prevent tumour recurrence)
Which canine cancer can be preventatively treated with using a anti-cancer vaccine? How does it work?
Canine melanoma. The vaccine contains the DNA for the human gene tyrosine. This protein is found on normal and cancerous melanocytes. The protein that is generated in vivo in the dog is different enough from ‘self’ antigens that an immune response is triggered, however the resulting antibody is similar enough that it can attack cancerous melanocytes.
Some chemotherapy protocols aim to deplete the immune system and target destruction of rapidly dividing cells. How is immunomodulation different to this approach?
Immunomodulation aims to trigger and heighten the immune system to become more sensitive in its screening for cancer cells. Administration of cytokines (such as interleukins and interferons) is an example of this.
What role do interleukins play in cell signalling, during the innate immune response?
Promote lymphocyte, monocyte and macrophage proliferation
Activate NK cells
Mediate inflammation
What role to interferons play in immunomotherapy?
Antiviral, antiproliferative, immunomodulatory
Which serological test could be used to diagnose FIV?
Western blot (electrophoresis)
Which diagnostic serological test can be used to help diagnose myasthenia gravis?
Radioimmunoassay
How do corticosteroids work to dampen the immune system?
Decrease circulating T cells
suppress complement activity
Decrease migration of neutrophils, macrophages and monocytes
List the side effects of long term corticosteroids
- Fat stores shift from limbs to trunk
- Predisposed to secondary infections due to dampened immune system
- Increased serum triglycerides and cholesterol (potentially leading to hypercoagulable state)
- Gluconeogenesis is increased, can lead to diabetes mellitus
- Secretion of pepsin, gastric acid and trypsin increased, increasing risk of gastro/duodenal ulceration
- Hypertension as cortisol increased bp
- Can cause raised liver enzymes
Which steroid provides the most potent immunosuppression, when compared to hydrocortisone?
Dexamethasone (7-20 times activity). Prednisone/prednisolone has 1-4x activity of hydrocortisone.
Compare dexamethasone with prednisolone and prednisone in terms of duration of activity
Dexamethasone longest duration of activity (48hrs).
Preds less (12-36hrs)
In which patients would prednisolone be advised over prednisone?
Patients with liver failure or cats who are unable to convert prednisone to bioactive prednisolone would need to be prescribed prednisolone.
What is the side effect of using azothioprine in cats?
Severe bone marrow suppression. Should not be used in cats.
Which vaccines for dogs are recommended as “core” in North America? 4 marks
Rabies, canine distemper, canine parvovirus, canine adenovirus
Which vaccines for dogs are considered non-core vaccines in North America ?
Leptospirosis, bordetella bronchiseptica, canine infectious respiratory disease complex, borreliosis, canine influenza virus
Which vaccines are not recommended for dogs in North America
Giardia, canine measles, canine coronavirus, rattlesnake vaccine, canine adenovirus-1, porphyromonas dentsl vaccine.
Which feline vaccines are considered “core” for felines in North America
Feline rabies, feline parvovirus, feline upper respiratory disease complex, feline calicivirus, feline herpesvirus
Which vaccines are considered non-core vaccines for felines living in North America ?
Feline leukaemia virus, chlamydia, bordetella, feline immunodeficiency virus
Which vaccines are not recommended in felines in North America?
Giardia, feline infectious peritonitis (coronavirus)
