SAM II Final Exam - Hematology Flashcards
T/F: The majority of dogs with IMTP have a platelet count of <20,000/uL
True
A doberman has been diagnosed with vWD. There are a number of therapies available for managing hemorrhage crises or used in the anticipation of surgery in this disease. Which is not a treatment option?
- Fresh whole blood
- Plasma
- Fresh frozen plasma
- Cryoprecipitate
- Desmopressin
Plasma
- Plasma has no value in blood transfusion at all.*
- Fresh whole blood would be helpful, but you would be increasing the risk of overperfusion. Fresh frozen plasma would be ideal. Cryoprecipitate would be the best option (has a very high concentration of vWF and factor 8). Desmopressin will have an onset within 30 minutes and a duration of action of 2 hours, where it will increase the release of vWF from platelets and endothelium
In the treatment of IMHA, what is the main benefit of using Mycophenolate mofetil instead of Azathioprine?
Mycophenolate does not cause bone marrow suppression
Azathioprine does.
If you note petechiations on the ventrum, perineal area, and/or gums, is this more likely a primary or secondary hemostatic disorder?
primary
A dog presents with a 24 hour history of weakness and anorexia. Clinical exam: pale mm and tachycardia. The owner complaint is red urine. Hematology detects a moderate anemia (PCV 25%), non-regenerative, normocytic, normochromic. The serum is red discolored. What is your likely diagnosis?
- Intravascular hemolytic anemia
- Bone marrow destruction
- Blood loss anemia
- Extravascular hemolysis
Intravascular hemolytic anemia
- Even though this dog is non-regenerative, there has been a massive decline in its PCV. This dog is showing signs of shock as the result of a hemolytic crisis (something that has dramatically decreased its oxygen capacity).*
- This could be anything that leads to lysis of the RBCs, including Heinz body anemia and IMHA*
Spherocytosis is a hallmark of __________ disease
Spherocytosis is a hallmark of immune-mediate disease
Due to immune opsinisation of RBC and piecemeal removal of the membrane
The most common blood type in cats is:
Type A
-
Blood groups: A, B and AB (MIK)
- Type A is most common
- Type B varies in frequency depending on the breed
- AB is rare
- Naturally occurring alloantibodies
- Need to be blood typed before first transfusion
- Crossmatching must be performed before subsequent transfusions
T/F: Polychromasia is a hallmark of regeneration
True
A dog presents with respiratory distress due to hemothorax. Which of the following potential etiologies is incorrect?
- Warfarin toxicity
- Advanced liver failure
- Hemophilia
- Angiostrongylus vasorum (French heartworm)
- Thrombocytopenia
thrombocytopenia
- It’s likely that the hemothorax was the cause of the thrombocytopenia, not the other way around. Additionally, even if this happened spontaneously, low platelet count or low platelet function is incapable of causing a massive cavity bleed.*
- This has to be a secondary coagulopathy.*
What are the two forms of reticulocytes in cats?
aggregate and punctate
The only way to prove a dog has Evan’s Syndrome is by the use of:
flow cytometry
T/F: Uremia may cause thrombocytopathy
True!
While not widely available, this test is currently the most sensitive and specific way to test and diagnose Vitamin K antagonism:
PIVKA
- Protein Induced by Vitamin K Absence*
- PIVKA can detect coumarin or warfarin toxicity as early as 12 hours after ingestion*
With marked thrombocytopenia, platelet count is less than _________
50,000
With marked thrombocytopenia, platelet count is _< 50,000/uL_
- Rule out infectious diseases
- Rule out neoplasia
- Bone marrow assessment
- (AntiPLT Ab tests not routinely available)
- Dx = Autoimmune Thrombocytopenia if all 2˚ causes ruled out
You suspect IMTP in one of your patients, so you send some blood out for PCR to help rule out infectious disease. What drug might you start the patient on while you’re waiting for the PCR results?
doxycycline
Immunosuppressive drugs are the key to treating ITP; however, because results of serology for infectious causes of immune-mediated thrombocytopenia may be delayed, concurrent treatment with doxycycline is often initiated with immunosuppressive drugs.
What transfusion products would be indicated in the case of thrombocytopenia?
fresh whole blood, platelet rich plasma, platelet concentrates
What is your first step of treatment if you note signs of a transfusion reaction?
STOP THE DAMN TRANSFUSION
- Stop transfusion immediately
- Record everything!!!!
-
If histamine-related signs, give:
- Antihistamine +/‐ Dexamethasone
-
If anaphylactic shock:
- Oxygen +/‐ artificial ventilation
- Adrenaline IV
- IV fluids
- Antihistamines (e.g. Piriton) and H2 blockers
- Dexamethasone
____ mL/kg of donor blood will raise recipient PCV by 1%
2.2 mL/kg
2.2 mL/kg of donor blood will raise recipient PCV by 1%
What are some causes for an increased MCV?
- Regenerative (reticulocytes)
- Toy breeds
- Cats with FeLV and myeloid dysplasia
- Artifact (agglutination)
The image below is the ventral abdomen of a Miniature Schnauzer. Is this an example of primary or secondary hemostasis?
primary hemostasis
Note the petechiation. This is a thrombocyte number or function abnormality
Which glucocorticoids are most commonly used to treat IMHA?
prednisone and dexamethasone
- Prednisone 2mg/kg/day
- Dexamethasone 0.25-0.5 mg/kg/day
T/F: Blood transfusions raise the patient’s platelet count
False
If we repeat a hematology after receiving a platelet transfusion, there will be no change in the platelet count, but whole blood may contain enough platelets to stop hemorrhage
The mainstay of treatment for IMHA is __________ therapy
Immunosuppressive
glucocorticoids are our go-to drugs
If you note hematomas, hemarthrosis, or bleeding into cavities , is this more likely a primary or secondary hemostatic disorder?
secondary