Hematology Flashcards
What is the optimal number of saline washes to remove most RBC storage lesions without causing excessive RBC fragility?
One wash
JVIM 2021, Coll
Does K+ increase or decrease in a blood transfusion during storage and why? What are two scenarios where this could be clinically relevant?
K+ incr d/t declining Na/K ATPase
Usually not clinically relevant unless 1) already hyperkalemic or 2) massive xfusion
JVIM 2021, Coll
True or False:
A large prospective study of dogs receiving leukoreduced pRBC transfusions vs non-LR found that LR-pRBC dogs had fewer transfusion reactions and improved post-xfusion PCV.
False – no difference in xfusion reactions, PCV, hospitalization time, or survival.
JVIM 2021, Radulescu
What is the most common pRBC transfusion adverse reaction and its prevalence?
Febrile nonhemolytic transfusion reaction (FNHTR), 8%
JVIM 2021, Radulescu
True or False:
Peristaltic infusion pump (PIP) had slightly increased hemolysis compared with gravity delivered pRBC transfusion.
True
JVIM 2021, Blasi-Brugue
Are blood donations from first time or repeat donors more likely to contain infectious organisms?
First time donors
JVIM 2021, Nury
What are the unique features of greyhound blood?
–RBC size and number
–WBC number
–Plt number
–VCM clot strength and lysis
–Higher HCT, Hb, MCV –> higher viscosity
–Lower WBCs
–Lower plt
–VCM – weaker clot, incr lysis
JVIM 2021, Chang
What is the thrombin clotting time (TCT)?
Prolonged PT and PTT with normal TCT is nearly pathognemonic for what condition?
TCT: add thrombin to sample which converts F5 –> F5a, not affected by inhibitors
Acquired F5 inhibitors
JVIM 2020, Masciana
What is Glanzmann’s thrombasthenia?
Absent or low GP2b3a (fibrinogen receptor – needed for plt aggregation)
JVIM 2020, Li
What complications are expected with protein C deficiency?
How is congenital protein C deficiency diagnosed?
How is it treated?
–Thrombosis
–Repeatably low protein C + exclusion of acquired causes (liver failure, PSS, sepsis, DIC)
–Anticoagulants (such as rivaroxaban)
JVIM 2020, Kelly
What is eltrombopag and what condition can it help treat? When would you expect to see a response?
–Thrombopoietin receptor agonist – but also seems to stimulate multiple cell lines
–Tx idiopathic aplastic pancytopenia (along with immunosuppressives)
–Respond at ~1mo
JVIM 2020, Kelly
How do amounts of glutathione, ROS, and vit E compare in anemic vs non-anemic dogs?
Anemic: lower glutathione (antioxidant), slightly higher vit E
No difference ROS
JVIM 2020
A recent study compared a new formulation of lyophylized platelets (LP) with canine cryopreserved platelet concentrate (CPP).
–How did these compare with respect to bleeding scores, plt count, and TEG over time in thrombocytopenic dogs?
–What are some practical advantages of LP over CPP?
–Both had similarly decreasing bleeding scores, no change in plt or TEG (r/o similar efficacy vs no efficacy at all)
–LP is stable at room temp, longer shelf life, smaller volume
JVIM 2020, Goggs
How does the concentration of neutrophil extracellular traps (NETs) change in stored pRBCs over time and why?
What is the effect of prestorage leukoreduction on this?
What transfusion adverse effect implicates NETs as a contributor (in human studies)?
–NETs increase over time – poss due to hemolysis –> free Hb activating neuts. The supernatant does not activate them.
–Reduced by prestorage leukoreduction
–TRALI
JVIM 2020, Mcquinn
Regarding blood crossmatching (CM):
–What two basic reactions could indicate incompatibility?
–How do in house tube based kits compare with reference lab tube agglutination assay? Which of the above two reactions do the in house kits not look for?
–Agglutination and hemolysis
–IH kits don’t look for the latter
–IH kits missed the vast majority of incompatible CMs
JVIM 2020, Marshall
–What is the prevalence if incompatible crossmatch (CM) among transfusion naive vs previously transfused dogs?
–What were two risk factors for CM incompatibility? What was the most common underlying disease for both?
–True or false: Hemolytic transfusion reactions have not been reported in transfusion naive dogs.
–Naive 25%, prev transfusion 35%, similar magnitude of CM incompatibility reaction for both
–Hemolysis, low HCT – most were IMHA
–True – questions the clinical relevance of CM incompatibility in xfusion naive dogs
JVIM 2020, Marshall
A recent study found 5 novel naturally occurring Ab in cats apart from the already established blood types A, B, AB. What practical point does this make about our procedures for feline blood transfusions?
Always crossmatch, even if transfusion naive
JVIM 2020, Binvel
4yr FS lab 1hrs post op laparoscopic liver bx and still hasn’t recovered from anesthesia. Her mm are pale and her StO2 (tissue oxygen saturation) is <87%. What is wrong with her?
StO2 <87% –> shock (in this case, due to hemorrhage)
JVECCS 2019 Gray
How can hypocobalaminemia lead to megaloblastic anemia?
No B12 –> impaired DNA synth in RBC precursors –> apoptosis, phagocytosis
Some megaloblastic RBCs escape censor and make it to circulation
JFMS Olsen 2019
11yr MN mixed breed with 1 month hx vomiting, hyporexia, and rapid weight loss. Chronic enteropathy is a top ddx. Screening CBC showed moderate anemia, polychromasia, eccentrocytes, and keratocytes.
Does this increase or decrease suspicion for primary GI disease? If the former, is IBD or LSA more likely?
Anemia + at least 3 morphologic abnormalities (esp eccentrocytes) increases likelihood of chronic enteropathy, esp LSA
JAVMA 2019 Parachini-Winter
Which is true about samples obtained via pre-heparinized syringes? Jugular vs peripheral IVC?
A) It alters RBC indices
B) It alters plt morphology
C) It alters some biochemistry parameters
D) Some statistical, but no clinical differences for CBC and biochem values
D for both
JFMS 2021 Cook
JVIM 2022 Guarino
In an ICU setting, high RDW is a predictor of all-cause mortality for:
A) Dogs
B) Cats
C) Neither
C
JVECC 2022 Ludwik
JVECC 2022 Pfeifer
Procyte CBCs can underestimate neutrophil counts. How can you check for accuracy, OTHER than doing a manual diff?
Procyte misreads neuts as lymphs, monos esp in dogs with systemic inflammation
Look at dot plot. If the colored smears are all mashed together rather than distinct patches, it’s inaccurate.
JSAP 2022 Bergstrand
Which neoplastic phenotype is most common in cats with peripheral lymphocytosis?
Rank them from best to worst prognosis. For the one with the BEST px, list at least two factors that WORSEN px.
CD4+ T cell
CD4-CD8- (double neg) T cell
CD5 low expressing T cell
Most common: CD4+
CD4+ 2yrs > DN T cell 9mo > CD5 low <1mo
CD4+ – worse if abdominal lymphadenopathy, intestinal involvement, female
JVIM 2020 Rout
2yr FI Ragdoll with microcytic, hypochromic, nonregenerative anemia. She is mildly lethargic, otherwise aclinical. No GI signs. She is indoor only and fed a commercial raw diet.
What is your top differential?
Iron deficiency anemia due to aberrant diet
Most commercially available foods that are low in Fe, Cu, Zn are raw diets
JFMS 2022 Summers
True or False: Like handheld glucometers, handheld lactatometers are prone to error compared with tabletop analyzers.
False – lactatometers are very accurate
JVECC 2020 Acierno
True or False: IH ammonia tends to read lower than the reference lab but usually not significant enough to affect interpretation.
True – high agreement with interpretation as either normal or high
JAVMA 2018 Funes
In cats with pancytopenia due to myelodysplastic syndrome (MDS), which bone marrow cell line is usually most significantly affected?
A) Granulocytes
B) Lymphocytes
C) Erythrocytes
D) Megakaryocytes
E) All equally affected
C
JFMS 2019 Turinelli
What characteristics might be seen on LN sampling in dogs with sterile lymphadenitis?
A) Neutrophilic
B) Granulomatous
C) Pyogranulomatous
D) Necrotic
E) All of the above
F) None of the above
E) All of the above
JSAP 2019 Latre
Regarding sterile lymphadenitis:
–Overrepresentd signalment?
–Most common CS/PE findings?
–Tx?
–Px?
Young to middle aged FS English springer spaniels
Most will have fever, lymphadenopathy, skin lesions; can see a lot of other stuff too (GI, resp, epistaxis)
Most dogs respond to pred –> rapid resolution of CS and lymphadenopathy. Uncommon to relapse.
JSAP 2019 Latre
JSAP 2019 Dor
True or False: LN aspiration performed with a syringe rather than a naked needle yields a better sample.
False – both are comparable
JSAP 2022 Karakisou
Which affect coagulation testing (PT/PTT, VCM) in cats?
A) Needle gauge
B) Difficulty of venipuncture
C) Both
D) Neither
D
JFMS 2019 Solbak
Match the following VCM parameters with the conventional tests they correlate with.
Intrinsic activated clot time
Extrinsic activated clot time
Max clot firmness
—-
PT
PTT
Fibrinogen
Intr CT - PTT
Extr CT - PT
Fibrinogen - Max clot firmness
JVIM 2019 Enk
Which decreases intra-individual variation with VCM?
Fresh whole blood
Citrated whole blood
Fresh
JVECC 2020 Wang
Which may exacerbate poor clotting in dogs with hemoabdomen?
A) Crystalloids
B) Colloids
C) Both
D) Neither
B) Colloids
Longer time to clot and decreased clot firmness via TEG, though PT/PTT were not different between crystal vs colloid groups
JVECC 2021 Lannucci
What is one possible advantage of the turbidimetric ACL-TOP 300 analyzer over PT, PTT?
May be more sensitive to detect hypocoagulable patients
JVECCS 2019 Sharkey
True or False: PLN dogs need a higher clopidogrel dose than healthy dogs to achieve platelet inhibition.
False
Standard dosing is adequate based on ADP plt aggregometry
JVIM 2020 Shropshire
Which is true about dogs post splenectomy for splenic masses?
A) They have testing consistent with hypercoagulable state which peaks at 1 week post op
B) If they had hemoabdomen, they are hypocoagulable post op and it takes a median of 1 week to normalize
C) Hypercoagulable testing correlates strongly with risk of thromboembolism
D) Portal vein thrombosis and PTE are common post spenectomy complications
A
Often hypercoag on paper by 1 week out (plts, VCM), not assoc with hemoab or PVT/PTE, significance is unknown
JAVMA 2020 Phipps
True or False: Atorvastatin (a statin) reduces coagulation in humans but may increase coagulation in dogs.
True per VCM in healthy dogs, but clinical significance unknown
JSAP 2019 Bonaparte
List at least 3 congenital and 3 acquired causes of hyperfibrinolytic disorders.
What is one potential general treatment for hyperfibrinolytic disorders?
Congenital:
Hemophilia A, B, C – missing clotting factor –> make loose, easily disrupted fibrin
F13 deficiency (fibrin stabilizing factor) – rare
Breed (Greyhound) - low alpha-2-antiplasmin (fibrinolysis inhibitor), antithrombin
Acquired:
DIC
Cavitary effusions
Liver failure
Lungworm (A. vasorum)
Trauma induced coagulopathy
Aminocaproic acid – promotes antiplasmin, inhibits plasminogen activators
JSAP 2019 Birkbeck
What are four diseases with strong indication for thromboprophylaxis?
IMHA (dogs only)
PLN
Panc (dogs only)
Cardiomyopathy (cats only)
JVECCS 2019
Match the following:
Low velocity, low shear
High velocity, high shear
Arterial thromboembolus
Venous thromboembolus
Anti-plt drugs are best
Anticaogulants are best
Venous (low velocity/shear) –> anticoag
Arterial (high velocity/shear) –> anti-plt
JVECCS 2019
Which anticoagulants should you avoid?
LMW heparin
Unfractionated heparin
Warfarin
FXa inhibitor
UF heparin, warfarin – less safety/efficacy studies OR known to be less safe
JVECCS 2019
Which should you wean rather than abruptly discontinue and why?
LMW heparin
Unfractionated heparin
Warfarin
FXa inhibitor
UF heparin, +/- FXa inhibitor. Abrupt d/c –> rebound incr thrombin, hypercoag.
JVECCS 2019
Which is true about antithrombotics and invasive procedures?
A) Should d/c 5-7 days prior to procedure in all patients, regardless of their thromboembolic risk.
B) Continue some or all antithrombotics in high risk patients.
C) Should wait 3-5 days post procedure to restart drugs.
B
If high risk, cont one anti-plt drug +/- antiocagulant (do procedure at drug nadir) OR if discontinuing, restart immediately post op as long as no bleeding
JVECCS 2019
Which POC test correlates best with rivaroxaban specific anti-Xa activity (RIVA)? How long post dose should you test?
Rapid-TEG (TF+Koalin)
Koalin TEG
TF TEG
PT
PTT
PT - excellent correlation
TF TEG > RapidTEG > Koalin TEG. If using TEG, get a baseline prior to starting Xa inhibitor.
Test at 3hrs post pill (peak effect)
JVECC 2021 Lynch
You are treating an ITP patient with therapeutic plasma exchange. He has a pulmonary bleed. For TPE, do you use heparin or regional citrate?
Regional citrate – some will be absorbed systemically and can cause hypocalcemia, but is overall less bad than heparin in a bleeding patient
JVIM 2019 Francey
What is the most common adverse effect of therapeutic plasma exchange? How can you prevent it?
Allergic – chemosis, hives, laryngeal swelling
Pre med with diph (very effective)
JVIM 2019 Francey
For methemoglobinemia, what is the threshold (%MetHb) for clinical cyanosis, fatal methemoglobinemia?
> 15%
70%
JVIM 2019 Jaffey
1.5yr MN DSH with exercise intolerance and cyanotic mm. SPO2 is 95%. What is your top differential?
When this is a congenital issue, what is the pathophys?
Methemoglobinemia. SPO2 may read low but is still inaccurate.
Broken CYB5R –> can’t reduce MetHb back to Hb
JVIM 2019 Jaffey
Which have been linked to hemolytic reactions after pRBC transfusion?
DEA 1
DEA 4
DEA 7
Dal
DEA 1, DEA 4, Dal
JVIM 2019 Guidetti
What is the major advantage of using a closed vs open collection system for feline blood donation?
Faster
JFMS 2020 Binvel
What percentage of cats experience an adverse reaction post blood donation?
1%
JFMS 2022 Abreu
What parameter on AUS can be used to assess fluid status? Does this work in dogs, cats, both?
CVC diameter, dogs only
JFMS 2022 Sanger
Which crossmatch method has the lowest rate of detecting incompatible matches? How does this relate to clinical adverse xfusion reactions?
Reference lab tube agglut
IH tube agglut
Immunochromatographic strip
Immunochromatographic strip. In this study, it detected only 1 incompatible crossmatch and that dog had an acute hemolytic xfusion reaction. Needs more study but may be more clinically useful than the other methods (50-85% incompatible matches, but clinically well tolerated xfusions).
JVECC 2022 Zaremba
True or False: Cats have inherent Ab against dog blood, and vice versa. Xenotransfusion is a last resort and a crossmatch should be done prior.
True
JFMS 2019 Priolo
JFMS 2022 Tinson
Which increase hemolysis in stored pRBCs?
A) Stored upright
B) Stored horizontally
C) Mixing daily
D) Mixing weekly
E) None of the above
E
JVECC 2022 Aumann
What is the threshold for acceptable level of hemolysis in stored blood prior to transfusion?
<1%
JVECC 2019 Ferreira
You have a critically anemic patient and need to rapidly transfuse.
–Is gravity or max pump rate (999mL/hr) faster?
–Which are assocaited with increased hemolysis? Gravity, pupm, syringe bolus, pressure bag
Same speed
None
JVECC 2021 Weeks
Regarding complications with pRBC xfusions in dogs:
–Overall complication rate? % life threatening complications?
–Most common complications (3)?
–Effect of leukoreduced vs regular pRBCs on complications?
19%, 1%
Fever, GI, hemolysis
Leukoreduced –> fewer fevers
All complications were more common with older pRBCs
JVECC 2022 Davidow
How does leukoreduced vs non-LR pRBCs affect:
WBC count
CRP
Fibrinogen
Lactate
Non-LR: higher CRP, fibrinogen, lactate
No difference WBC count
JVECC 2019 Lozano
Regarding plasma:
–How long is refrigerated plasma (incl previously frozen) good for?
–How does thawing method (warm water, flowing water, dry plasma thawer) affect its components?
About a month
Statistically but not clinically significant changes to clotting factors and vWB
JVECC 2022 Chee
JSAP 2019 Torkildsen
Which increases the risk of plasma transfusion reaction?
A) Lack of crossmatch
B) Multiple transfusions
C) Both
D) Neither
B
Crossmatch is not needed!
JVECC 2021 Santo-Domingo
Which are lower in Greyhounds? Does this affect their candidacy as plasma donors?
Clotting factors
vWB
Fibrinogen
Albumin
Platelets
vWB, Fibrinogen
No – they still meet minimum requirements
JVIM 2019 Drinkhouse
List 3 indications for cryo-poor plasma (cryosupernatant).
Vit K coagulopathy
Hemophilia B (F9)
Hypoalbuminemia
JVECC 2019 Culler
What is the minimum time that reconstituted canine serum albumin is good for in the fridge?
At least 24hrs
JVECC 2021 Mastrocco
True or False: A leukemoid response (neuts >50K) is strongly associated with all-cause mortality.
False – only weak correlation with nonsurvival
JVIM 2020 Ziccardi
How is the immature reticulocyte fraction (IRF) measured? What is the utility of this test?
Flow cytometry
Differentiate pre- vs nonregen anemia
(Higher IRF in preregen and regen anemia vs nonregen)
JVIM 2023 Jung
What is carboxyhemoglobin? What is the utility of this test? Limitations?
Hb metabolism –> carbon monoxide –> COHb
Marker of hemolytic vs other causes of anemia, much higher sens/spec than other markers (ex: Tbili, slide agglut, etc)
Not commercially available and not associated with prognosis
JVIM 2023 Nivy
True or False: Dogs with spontaneous hemoperitoneum are hyperfibrinolytic (hypocoagulable). After hemorrhage is addressed surgically, they should be treated with antifibrinolytics post op.
False – hyperfibrinolysis resolves quickly once bleeding is stopped
JVECC 2023 DeStefano
What gene is associated with delayed postop hemorrhage in Scottish deerhounds?
SERPINF2 - encodes antiplasmin
JVIM 2023 Court
What is the minimum PCV of a body fluid (ex: effusion, urine) to determine blood type using immunochromatographic cartridge?
PCV >/= 3%
JVECC 2023 Garcia-Arce
