Lab Med Blood Disorders & Malignancy

Question 1

What are the 2 broad categories of bleeding disorders?

Answer 1

1. Coagulopathy

2. Platelet disorder

Question 2

Coagulopathies include… (4)

Answer 2

• intrinsic factor defect
• extrinsic factor defect
• combination defect
• hypercoagulable state (inherited or acquired)

Question 3

Platelet disorders include… (2 categories, 5 disorders)

Answer 3

Thrombocytopenia

• -Drug Induced
• -ITP (immune thrombocytopenic purpura)
• -Heparin-Induced:Immune Mediated

Platelet Dysfxn

• -Acquired
• -Inherited

Question 4

Coagulopathy vs. Platelet Disorder (amount of bleed after surface cut)

Answer 4

Coag: Normal to slight increased time

Plt: Excessive, prolonged

Question 5

Coagulopathy vs. Platelet Disorder (onset of bleed after injury)

Answer 5

Coag: Delayed bleed after sx or trauma // Spontaneous bleed into joints or hematoma development

Plt: Immediate bleeding

Question 6

Coagulopathy vs. Platelet Disorder (clinical presentation)

Answer 6

Coag: Deep & excessive bleeding into joints, muscles, GI tract, and GU

Plt: Superficial & mucosal bleeding (GI, gingival, nasal), Petechiae, ecchymosis

Question 7

Initial labs for bleeding disorders

Answer 7

-PT/PTT
-CBC
-Platelet count – in CBC
-DIC Panel:
D-dimer
Fibrinogen
Peripheral blood smear

Question 8

When looking at labs for platelet disorders you should…

Answer 8

• consider if it’s low count or dysfunction
• Focus on PLT count 1st – if low then we have thrombocytopenia
• If PLT disfxn - count could be normal, just not working/or inhibited fxn

Question 9

When looking at labs for coagulopathy you should…

Answer 9

• Focus on PT and PTT values
• If one or both are elevated there is a coagulation defect.
• Think clotting cascade and coagulation factors involved.

Question 10

Define thrombocytopenia

Answer 10

LOW PLT count < 90,000 cells/uL

Question 11

What can cause low plt count?

Answer 11

Most Common is Drug-induced – R/o with medication reconciliation and short discontinuation of causative agent prior to procedure then resume after recovery period. (Clopidogrel, Enoxaparin, etc.)

Question 12

Would would severely low platelets indicate?

Answer 12

ITP (immune thrombocytopenic purpura)

*exclude DIC after running a negative panel

Question 13

What would delayed low platelets indicate?

Answer 13

Heparin-induced: Immune-mediated

• usually 4-14 days after initiated heparin treatment.
• Confirmed with LAB order = PF-4 antibodies

Question 14

What plt count would you see in plt dysfunction that’s acquired?

Answer 14

NORMAL - PLT count 150-400 x 10,000cells/uL

Question 15

What is on your diff dx for acquired plt dysfunction?

Answer 15

• Severe Liver Dz
• HELLP syndrome(seen in pregnancy with pregnancy-induced HTN)– Hemolysis, elevated liver enzymes, & low plts.
• Cirrhosis, End Stage Liver Dz.
• Severe Renal Dz (ARF/CRF, HUS, ESRD)
• DIC
• Aspirin use
• Multiple myeloma

Question 16

What plt count would you see in plt dysfunction that’s inherited?

Answer 16

NORMAL - PLT count 150-400 x 10,000cells/uL

Question 17

What is on your diff dx for inherited plt dysfunction?

Answer 17

• Bernard-Soulier Syndrome
• Glanzmann’s thrombasthenia
• Storage Pool Disease

Question 18

What is the treatment for both acquired and inherited plt dysfxn?

Answer 18

*give them normal platelets
MEDS: Desmopressin, OCPs (oral contraceptive pills), and FFP (fresh, frozen plasma - used in severe cases when plt infusion doesn’t work) or cryoprecipitate

Question 19

What 3 steps do you follow to confirm plt disorder?

Answer 19

1 Confirm Platelet Count in citrated blood

#2 Repeat CBC, peripheral blood smear and 1 HR post transfusion platelet count.
*Distinguish between LOW PLT PRODUCTION/pancytopenia/ small plts/or increased plt count following plt transfusion.
*AND INCREASED PLT DESTRUCTION large plts/ no significant increase in plt count post transfusion.
#3 Obtain bone marrow biopsy with cases of severe thrombocytopenia

Question 20

What do you focus on for coagulation defects?

Answer 20

PT/PTT

Question 21

What do you expect to see for intrinsic coagulation defects?

Answer 21

Normal PT
Elevated PTT

Dx = heparin use
*could order mixing study

Question 22

What do you expect to see for extrinsic coagulation defects

Answer 22

Elevated PT

Normal PTT

Question 23

What do you expect to see for combined coagulation defects

Answer 23

Elevated PT

Elevated PTT

Question 24

What is a mixing study?

Answer 24

Lab tech mixes equal amounts of the patient’s plasma with normal value plasma and then rerunning the PT and PTT tests on the mix

Question 25

What is your diff dx if after mixing study, PTT is now normal?

Answer 25

DIAGNOSIS: - Factor VIII deficiency (Hemophilia A, sort of Von Willebrand) - Factor IX deficiency (Hemophilia B) - Factor XI deficiency (Hemophilia C) - All intrinsic factors * Order each of these Factor tests to confirm which deficiency.

Question 26

What is your diff dx if after mixing study, PTT is still elevated?

Answer 26

DIAGNOSIS: - Factor VIII inhibitor - Factor IX inhibitor - Factor XI inhibitor * Order each of these Factor tests to confirm which inhibitor.

Question 27

Hemophilia A is deficiency in which factor?

Answer 27

VIII (8)

Question 28

Hemophilia B is deficiency in which factor?

Answer 28

IX (9)

Question 29

What will occur in both hemophilia A/B after mixing study?

Answer 29

Both fall under Intrinsic coagulopathy, therefore initially the PTT will be elevated and then normalize after mixing study.

Question 30

What is your diff dx if PT is elevated? (extrinsic coagulation defect)

Answer 30

-Early DIC -Liver Disease -Warfarin use -Vitamin K deficiency Confirm with empirical treatment of oral vitamin K to see PTT normalize

Question 31

How do you confirm early DIC?

Answer 31

Confirm with Panel D-dimer, fibrinogen, blood smear (see handout)

Question 32

How do you confirm liver disease?

Answer 32

Confirm with elevated LFTs, Hepatitis Panel (to come in GI)

Question 33

How do you confirm warfarin use?

Answer 33

Confirm with medication reconciliation

Question 34

How do you confirm vitamin K deficiency?

Answer 34

Confirm with empirical treatment of oral vitamin K to see PTT normalize

Question 35

What is your diff dx if both PT & PTT are elevated? (combined coagulation defect)

Answer 35

- Heparin use (confirm with medication reconciliation) - Severe DIC (confirm with DIC panel) - Severe Liver Disease (confirm with elevated LFTs, Hepatitis Panel) - Severe Vitamin K deficiency (confirm with empirical treatment of oral vitamin K to see PT normalize. Research probable cause to prevent continued deficit)

Question 36

What do you order if no previous diff dx is confirmed?

Answer 36

Then order FACTOR LEVELS (all 3) to see which one is low… - Factor II deficiency - Factor V deficiency - Factor X deficiency - Fibrinogen < 100mg/dl - VWD - Factor

Question 37

Hypercoagulation is commonly referred to as...

Answer 37

Thrombophilia

Question 38

Examples of inherited hypercoagulation (6)

Answer 38

- Most common = Factor V Leiden Deficiency - Prothrombin 20210 mutation - Protein C or S Deficiency - Anti-thrombin III Deficiency - Homocystinemia - Fibrinolysis Defects

Question 39

Examples of acquired hypercoagulation (9)

Answer 39

- Prolonged Rest - Immobilization - Smoking - OCP - Pregnancy - Nephrotic Syndrome - Cancer - DIC - Lupus anticoagulant

Question 40

What is another hypercoagulation?

Answer 40

Antiphospholipid Syndrome - APS

Question 41

What is APS?

Answer 41

Arterial or venous thrombosis or pregnancy loss and the presence of antiphospholipid antibodies

Question 42

Primary APS vs. Secondary APS

Answer 42

``` Primary if alone Secondary if associated with: --SLE --Rheumatic disorders --Or infection --Or medication ```

Question 43

Labs for APS

Answer 43

- Antiphospholipid Abs - Anticardiolipin Abs - Lupus Anticoagulant - B2-glycoprotein I Ab - Plus tests for inherited factors