Exam I Material Flashcards
If you have an abscess, would you expect to see neutrophilia or neutropenia?
Neutrophilia
T/F: Blood loss causes thrombocytopenia
False
Gotcha, biatch!
What is the most diagnostically useful finding in dogs with immune mediated hemolytic anemia (IMHA)?
Spherocytosis
While Greyhounds generally make great blood donors, many of them carry blood-borne diseases. The most common blood-borne disease, that we see in ~85% of greyhounds, is:
Babesia canis
~85% of Greyhounds carry positive titers for Babesia canis
What might be the cause of Heinz Body Anemia in a cat?
Anything that causes oxidative damage:
- Acetaminophen
- Propylene Glycol
- Onions, Garlic
- Lymphoma, hyperthyroidism, diabetes
Just to name a few
Briefly describe the formation of a primary hemostatic plug:
Adherence, Activation, Secretion, Aggregation
Platelets adhere to subendothelium and undergo activation (including shape change), secrete their granules, and aggregate to form a platelet plug
When are increased PIVKA values seen?
Proteins Induced by Vitamin K Antagonism (PIVKA) will be increased in:
- Vitamin K antagonism/deficiency
- Human hepatocellular carcinomas
What are the two blood systems in the cat?
**AB system **and Mik system
Briefly describe how neutrophils develop toxic change:
early release
Neutrophil “toxic change” is normally due to rapid multiplication and shortened maturation time in the bone marrow, resulting in persistence of ribosomes. This accelerated production rate is common in inflammation
T/F: DIC may be caused by induction or exposure of tissue factor or other activators of coagulation
True
Disseminated Intravascular Coagulation (DIC) may be caused by induction or exposure of tissue factor or other activators of coagulation. This may be observed in cases of sepsis, tissue necrosis, neoplasia, etc.
Which factor of the coagulation cascade is required for the initiation of secondary hemostasis?
Tissue factor (Factor III)
What is the significance of decreased fibrinogen concentration?
Significance of decrease:
- Consumption due to hypercoagulation (excessive conversion of fibrinogen to fibrin)
- Decreased production by the liver
What is the most prominent feature of a feline ‘excitement’ response?
Lymphocytosis
Increased blood flow through microcirculation results in shift of leukocytes from marginated pool to the circulating pool. This can result in a 2-fold increase in leukocyte concentration. Lymphocytosis is the most prominent feature of feline excitement response
Name a few diseases that may cause a reactive thrombocytosis:
- Chronic Inflammatory Disease
- Iron deficiency anemia
- Chronic hemorrhage
- IMHA
When crossmatching: If you do not observe agglutination, is that considered a positive or negative crossmatch?
Negative Crossmatch
If there is no agglutination or hemolysis, the recipient is not likely to have a transfusion reaction from the donor’s RBCs. Go ahead and transfuse!
Which morphological abnormality is commonly seen in red blood cells 24-48 hours following rattlesnake envenomation?
Echinocytes
What is the most common blood type in cats?
Type A
>95% of all cats have Type A blood
When examining a blood smear to analyze platelet concentration, what is the minimum number of platelets you should expect per high power field (100x)?
7-10 platelets
Horses: minimum of 4-7
Increased numbers of enlarged platelets suggests active production of platelets
Microcytic anemia in domestic animals is most often associated with:
Iron deficiency
Stabilization of the platelet plug via fibrin meshwork is referred to as:
Secondary hemostasis
This usually only occurs in large defects (In small defects –> platelets only)
What does Buccal Mucosal Bleeding Time evaluate?
Adequate platelet number and function
To perform the test, make a standardized incision, blot the blood gently, and measure time for bleeding to cease.
Normal time for dogs: 1-5 mins
Normal time for cats: 1-3.5 mins
T/F: Yellow coloration of plasma may be considered normal in large animals
True
Yellow coloration of plasma may be indicative of icterus in both small animals and large animals.
However, in large animals, it may be due to carotenoid pigments in their diet (in this case, it would be considered normal)
Dogs that are only DEA ____ and/or DEA ____ are often used as “universal donors”
Dogs that are only DEA 4 [+] and/or DEA 6 [+] are often used as “universal donors”
DEA 4 and 6 are expressed in 98% of dogs. Most dogs carry the antigen and do not develop antibodies.
T/F: Cats with Type B blood have strong natural isoantibodies against Type A, which can lead to severe and lethal transfusion reactions
True
Which laboratory tests could you use to test platelet concentration and morphology (size)?
Blood smear and hematology analyzers
When testing platelet concentration in blood, collect blood in EDTA tubes (purple/lavender top). The EDTA present in the tube binds calcium ions, stopping the coagulation cascade
Which feline blood type is associated with strong isoantibodies?
Type B
Cats with Type B blood have strong natural isoantibodies against Type A, which can lead to severe and lethal transfusion reactions
Heinz bodies are inclusions within red blood cells composed of:
oxidatively denatured hemoglobin
Cats are most susceptible to Heinz body formation. It occurs with diseases such as lymphoma, hyperthyroidism, and diabetes mellitus
If an animal has immune-mediated hemolytic anemia and immune-mediated thrombocytopenia, what is the name of this syndrome?
Evan’s Syndrome
What does a PCV value tell you?
Relative quantity of RBCs to whole blood
(what % of whole blood is made up of red blood cells)
Keratocytes are unique to which disorder?
Iron deficiency anemia
Which factor drives amplification of secondary hemostasis? Which 4 factors does it affect?
**Thrombin **is the key factor that promotes amplification of 2° hemostasis.
It affects factors Va, VIIIa, VII, and XI
The presence of macroplatelets is suggestive of:
increased platelet production
If you are given a blood panel and notice a low platelet count, but all other coagulation tests are normal, what should you be thinking with regard to this patient?
Immune-mediated thrombocytopenia [ITP]
This patient’s body is attacking its own platelets!!!
Polychromasia is indicative of:
blood loss or blood destruction with subsequent regenerative response
Polychromatophilic cells are young erythrocytes that have been released early
T/F: Most cats are Mik negative
False
_Most cats are *Mik *positive_. Cats without the Mik antigen have Mik alloantibodies.
What are the two major mechanisms of thrombocytosis?
- Increased production
- Increased distribution in plasma
Animals are usually asymptomatic with regard to the increased platelet count
What are the most immunogenic blood types in dogs?
**DEA 1.1 **and DEA 1.2
DEA 1.1: ~45% of population
DEA 1.2: ~20% of population
The presence of spherocytes is suggestive of:
Immune-Mediated Hemolytic Anemia [IMHA]
Spherocytes are erythrocytes that appear small and lack central pallor
What is the major regulatory enzyme for thrombopoiesis?
Thrombopoietin
Thrombopoietin is produced in the liver and the kidney. It stimulates the production and differentiation of megakaryocytes.
T/F: Hemorrhage alone is usually the cause of significant thrombocytopenia
False
Hemorrhage alone does not usually cause significant thrombocytopenia.
Exception: acute severe hemorrhage may result in mild thrombocytopenia
Which laboratory test is most likely to be helpful in determining whether a regenerative anemia is due to extravascular hemolysis or blood loss that occured the day before?
Plasma Protein Concentration (TP)
If the anemia is due to extravascular hemolysis, then the TP should be normal. However, if the anemia is due to blood loss, the TP should be decreased
What would be the most likely cause of lymphocytosis in a dog in St. Kitts?
Ehrlichiosis
In which animal is Rouleaux formation of RBCs considered normal? What does the formation suggest in other animals?
Rouleaux formation is normal in horses.
It suggests increased globulin in small animals
1/3 of platelets are found in the _________
spleen
T/F: Increased FDPs inhibit platelet function and fibrin polymerization
True
Increased Fibrin Degradation Product (FDPs) inhibit platelet function and fibrin polymerization ONLY when FDPs are pathologically increased (e.g. DIC). It is not a ‘normal’ control mechanism
What is the significance of increased fibrinogen concentration?
An increased fibrinogen concentration can be indicative of inflammation. You may also see a relative increase with dehydration.
In a major crossmatch, what is tested from the recipient?
What is tested from the donor?
In a major crossmatch, the patient’s serum and the donor’s RBCs are tested
Increased FDP and D-dimers are commonly associated with:
Disseminated Intravascular Coagulation (DIC)
If you see a lot of Fibrin Degredation Products (FDP) and D-dimers, you know there is a high amount of fibrinolysis taking place. The usual indication is DIC.
What are the 2 major blood systems in dogs?
**DEA **and Dal
DEA = Dog Erythrocyte Antigen
Dal = a common antigen in most dogs, but is lacking in some dalmations
If a patient’s platelet count is lower than the lower reference interval (LRI), the patient has:
thrombocytopenia**
The degree of thrombocytopenia is gauged based on how much lower the platelet count is than the reference interval.
If the patient has <20,000/µL, that patient could spontaneously hemorrhage!
T/F: Splenectomy is almost always required in the pathogenesis of hemolytic anemia associated with Mycoplasma haemocanis
True
Splenectomy predisposes animals to acute infection by Mycoplasma haemocanis