Oncology and Haematology SBAs Flashcards
Scenario: A rabbit is brought to your clinic for a routine health check. You need to collect a blood sample for haematology and biochemistry.
Lead-in: Which of the following is the most appropriate site for blood collection in this rabbit?
Options:
a) Lateral saphenous vein
b) Marginal ear vein
c) Cephalic vein
d) Jugular vein
e) Cranial vena cava
Answer: a) Lateral saphenous vein
Explanation: While all the options are potential sites for blood collection in rabbits, the lateral saphenous vein is generally preferred for small samples due to its ease of access and relatively low risk of complications.
Scenario: A ferret presents with lethargy and anorexia. You suspect hyperestrogenism and need to collect a blood sample to assess the severity of the anaemia.
Lead-in: Which of the following blood collection sites is most appropriate for this ferret?
Options:
a) Lateral saphenous vein
b) Marginal ear vein
c) Cephalic vein
d) Jugular vein
e) Cranial vena cava
Answer: d) Jugular vein
Explanation: In ferrets, the jugular vein is a suitable site for blood collection due to its relatively large size and accessibility. The other options are less ideal due to the ferret’s anatomy and the potential need for larger blood volume.
Scenario: A bird needs a blood sample for a health check. You are considering collecting the sample from the ulnar vein.
Lead-in: Which of the following is the most significant risk associated with ulnar vein blood collection in birds?
Options:
a) Cardiac puncture
b) Haematomas
c) Wing fracture
d) Tail autotomy
e) Lymphatic contamination
Answer: c) Wing fracture
Explanation: While haematomas can occur, the most significant risk associated with ulnar vein blood collection in birds is the potential for wing fracture, especially in conscious birds or those with fragile bones
Scenario: A snake presents for a health check, and you need to collect a blood sample.
Lead-in: Which of the following is the most commonly used site for blood collection in snakes?
Options:
a) Lateral saphenous vein
b) Ventral coccygeal vein
c) Cephalic vein
d) Jugular vein
e) Cranial vena cava
Answer: b) Ventral coccygeal vein
Explanation: The ventral coccygeal vein is the most commonly used site for blood collection in snakes due to its accessibility and relatively easy restraint. The other options are less ideal due to the snake’s anatomy or potential complications.
Scenario: A tortoise requires a blood sample for a diagnostic workup.
Lead-in: Which of the following blood collection sites is generally preferred for tortoises?
Options:
a) Lateral saphenous vein
b) Ventral coccygeal vein
c) Jugular vein
d) Subcarapacial vein
e) Cranial vena cava
Answer: c) Jugular vein
Explanation: The jugular vein is often preferred for blood collection in tortoises due to its accessibility and relatively low risk of lymphatic contamination. The other options can be more challenging or have a higher risk of complications.
Scenario: A rabbit blood smear shows a heterophil:lymphocyte ratio of 1:1.
Lead-in: What is the most appropriate interpretation of this finding?
Options:
a) Normal finding
b) Indicative of stress
c) Suggestive of infection
d) Consistent with chronic disease
e) Requires further investigation
Answer: a) Normal finding
Answer: a) Normal finding
Explanation: A heterophil:lymphocyte ratio of 1:1 is typically considered a normal finding in rabbits.
Scenario: A guinea pig blood smear reveals the presence of Kurloff cells.
Lead-in: Which of the following is the most likely cause of this finding?
Options:
a) Stress
b) Infection
c) Oestrogen stimulation
d) Anaemia
e) Young age
Answer: c) Oestrogen stimulation
Explanation: Kurloff cells are unique to guinea pigs and are produced by the thymus under the influence of oestrogen.
Scenario: A ferret blood sample shows a haematocrit (HCT) of 60%.
Lead-in: What is the most appropriate interpretation of this HCT value?
Options:
a) Normal finding
b) Indicative of anaemia
c) Suggestive of dehydration
d) Consistent with hyperestrogenism
e) Requires immediate blood transfusion
Answer: a) Normal finding
Explanation: Ferrets generally have higher HCT values compared to other mammals. A HCT of 60% is within the normal range for ferrets.
Scenario: A reptile blood smear shows a high number of heterophils with fusiform granules.
Lead-in: Which of the following is the most likely cause of this finding?
Options:
a) Normal finding
b) Oestrogen stimulation
c) Anaemia
d) Infection
e) Kurloff cells
Answer: d) Infection
Explanation: Heterophils are the reptilian equivalent of mammalian neutrophils. An increased number of heterophils often indicates infection or inflammation.
Scenario: A bird blood smear reveals a PCV of 30%.
Lead-in: What is the most appropriate interpretation of this PCV value?
Options:
a) Normal finding
b) Indicative of anaemia
c) Suggestive of dehydration
d) Consistent with polycythaemia
e) Requires immediate blood transfusion
Answer: b) Indicative of anaemia
Explanation: A PCV of 30% is below the normal range for most bird species, suggesting anaemia.
Scenario: A rabbit presents with a history of chronic respiratory disease. You perform a blood test and find that the total white blood cell count is within the normal range, but there is a relative lymphopenia.
Lead-in: What is the most likely explanation for this finding?
Options:
a) Normal finding
b) Physiological response to stress
c) Chronic stress or disease
d) Acute stress
e) Adrenaline release
Answer: c) Chronic stress or disease
Explanation: In rabbits, the total white blood cell count rarely increases significantly. Instead, the heterophil:lymphocyte ratio changes in response to stress or disease. A relative lymphopenia can be seen with chronic stress or disease.
Scenario: A ferret presents with pale mucous membranes and lethargy. You suspect anaemia.
Lead-in: Which of the following diagnostic tests is most likely to confirm regenerative anaemia in this ferret?
Options:
a) Bone marrow aspirate
b) Serum iron levels
c) Faecal occult blood test
d) Reticulocyte count
e) Blood glucose measurement
Answer: d) Reticulocyte count
Explanation: An increased reticulocyte count is a key indicator of regenerative anaemia, where the bone marrow is actively producing new red blood cells in response to blood loss or destruction.
Scenario: A dog presents with severe anaemia. The blood smear shows spherocytes.
Lead-in: Which of the following conditions is most likely associated with this finding?
Options:
a) Iron deficiency anaemia
b) Regenerative anaemia
c) Immune-mediated haemolytic anaemia (IMHA)
d) Liver disease
e) Splenectomy
Answer: c) Immune-mediated haemolytic anaemia (IMHA)
Explanation: Spherocytes are small, spherical red blood cells that lack central pallor. They are a strong indicator of IMHA in dogs, where the immune system is attacking and destroying red blood cells.
Scenario: A cat presents with pale mucous membranes, lethargy, and weight loss. You suspect feline leukaemia virus (FeLV) infection.
Lead-in: Which of the following tests is the most appropriate for initial screening for FeLV in this cat?
Options:
a) ELISA test for FeLV antigen
b) PCR test for FeLV provirus
c) Immunocytochemistry for FeLV proteins
d) Western blot for FeLV antibodies
e) IFA for FeLV p27 antigen
Answer: a) ELISA test for FeLV antigen
Explanation: ELISA tests for FeLV antigen are widely available, rapid, and cost-effective, making them suitable for initial screening. PCR tests are more expensive and typically used for confirmation or in cases with ambiguous ELISA results.
Scenario: A cat tests positive for FeLV antigen on an ELISA screening test.
Lead-in: Which of the following is the most appropriate next step?
Options:
a) Euthanize the cat
b) Isolate the cat from other cats
c) Perform a confirmatory PCR test
d) Commence treatment for FeLV
e) Monitor the cat for clinical signs
Answer: c) Perform a confirmatory PCR test
Explanation: False positives can occur with ELISA tests for FeLV. A confirmatory PCR test is recommended to verify the initial positive result before making further management decisions.
Scenario: A cat has a positive FeLV antigen test and a negative FeLV provirus PCR test.
Lead-in: Which of the following is the most likely stage of FeLV infection in this cat?
Options:
a) Progressive
b) Regressive
c) Abortive
d) Latent
e) Recovered
Answer: b) Regressive
Explanation: In regressive FeLV infection, the virus is controlled but still detectable by PCR, while antigen tests may be negative as the viral load is low.
Scenario: A client is concerned about their cat contracting FIV.
Lead-in: Which of the following is the most important risk factor for FIV transmission to emphasize?
Options:
a) Sharing food and water bowls
b) Mutual grooming
c) Close confinement
d) Bite wounds from an infected cat
e) Vertical transmission from mother to kitten
Answer: d) Bite wounds from an infected cat
Explanation: FIV is primarily transmitted through deep bite wounds, where saliva from an infected cat is inoculated into another cat. While vertical transmission can occur, it is less common.
Scenario: A cat presents with chronic gingivitis and stomatitis. You suspect FIV infection.
Lead-in: Which of the following diagnostic tests is most appropriate for confirming FIV infection in this cat?
Options:
a) ELISA test for FIV antibodies
b) PCR test for FIV provirus
c) Western blot for FIV p24 antigen
d) Lymph node aspirate for FIV RNA
e) Saliva test for FIV antibodies
Answer: a) ELISA test for FIV antibodies
Explanation: ELISA tests for FIV antibodies are the most common and reliable method for diagnosing FIV infection. PCR tests are less sensitive in the later stages of infection when antibody levels are high.
Scenario: A cat with clinical signs consistent with FIP has a positive FCoV antibody test.
Lead-in: What is the most appropriate interpretation of this result?
Options:
a) Confirms the diagnosis of FIP
b) Rules out the diagnosis of FIP
c) Indicates exposure to FCoV but not necessarily FIP
d) Suggests a need for euthanasia
e) Requires a confirmatory PCR test for FCoV
Answer: c) Indicates exposure to FCoV but not necessarily FIP
Explanation: Antibodies to FCoV are common in cats, and their presence does not definitively diagnose FIP. The diagnosis of FIP is challenging and often involves a combination of clinical signs, imaging, and laboratory findings.
Scenario: A shelter is considering implementing routine FeLV/FIV testing for all incoming cats.
Lead-in: Which of the following is the most important factor to consider when deciding whether to implement routine testing?
Options:
a) Cost of the tests
b) Prevalence of FeLV/FIV in the shelter’s population
c) Availability of isolation facilities
d) Risk of false positive results
e) Potential impact on adoption rates
Answer: b) Prevalence of FeLV/FIV in the shelter’s population
Explanation: The prevalence of FeLV/FIV in the population significantly influences the positive predictive value of the tests. In low prevalence populations, routine testing may lead to unnecessary euthanasia or isolation due to false positives.
Scenario: A rabbit presents with a history of chronic nasal discharge and sneezing. You suspect Pasteurella multocida infection. You collect a blood sample and find a leukocyte count of 12 x 10^9/L with the following differential:
Heterophils: 50%
Lymphocytes: 45%
Monocytes: 3%
Eosinophils: 2%
Lead-in: What is the most likely interpretation of this leukogram?
Options:
a) Normal leukogram for a rabbit
b) Leukogram suggestive of acute stress
c) Leukogram suggestive of chronic stress
d) Leukogram suggestive of inflammation, possibly due to Pasteurella infection
e) Leukogram suggestive of a lymphoproliferative disorder
Answer: d) Leukogram suggestive of inflammation, possibly due to Pasteurella infection
Explanation: While the total leukocyte count is within the normal range, the elevated heterophil percentage and slightly decreased lymphocyte percentage suggest inflammation. This could be consistent with the suspected Pasteurella infection.
Scenario: You examine a blood smear from a dog and observe the following cells (see image).
Lead-in: What is the most likely cause of this finding?
Options:
a) Liver disease
b) Iron deficiency
c) Immune-mediated haemolytic anaemia
d) Oxidative damage
e) Normal finding
Answer: a) Liver disease
Explanation: The image shows acanthocytes, which are red blood cells with irregularly spaced, blunt-ended projections. They are often associated with altered lipid metabolism, which can be seen in liver disease.
Scenario: You are examining a blood smear from a dog. The blood sample was drawn 2 hours ago and has been sitting in EDTA at room temperature since collection. You see the following cells (see image).
Lead-in: Which of the following is the most likely cause of this finding?
Options:
a) Sample artefact
b) Renal disease
c) Hepatic disease
d) Immune-mediated haemolytic anaemia
e) Oxidative damage
Answer: a) Sample artefact
Explanation: The image shows echinocytes, which are red blood cells with regularly spaced, spiky projections. While they can be associated with various conditions, they are most commonly an artefact of sample storage or preparation, especially in this case where the blood has been sitting in EDTA for a prolonged period.
Scenario: A 5-year-old Cocker Spaniel presents for a routine health check. You collect a blood sample and examine the blood smear, where you observe the following cells (see image).
Lead-in: Which of the following is the most likely cause of this finding?
Options:
a) Disseminated intravascular coagulation (DIC)
b) Iron deficiency
c) Immune-mediated haemolytic anaemia
d) Portosystemic shunt
e) Glomerulonephritis
Answer: a) Disseminated intravascular coagulation (DIC)
Explanation: The image shows schistocytes, which are fragmented red blood cells. Schistocytes are often a result of mechanical trauma to red blood cells, such as that seen in DIC.
