Unit 3

Question 1

Methods of Endpoint Detection

Answer 1

Electromechanical
 detects changes in the reaction mixture
 Optical Density
 detects changes in optical density as a result of clot formation
 Chromogenic
 detects color changes as the result of enzymatic reactions
 Immunologic
 detects and/or quantitates specific proteins

Question 2

What should QC Asses?

Answer 2

Testing reagents
– Testing personnel
– Testing methodologies

Question 3

How to asses QC results?

Answer 3

Levy-Jennings Charts

Question 4

Westgard rules

Answer 4

within 2.5 standard devs
no shifts
no trends

Question 5

Three types of factors of error

Answer 5

preanalytical
analytical
postanalytical

Question 6

Petechiae

Answer 6

Specific to vasculature/platelet problems

small red spots from localized bleeding

Question 7

Hemarthrosis

Answer 7

Problem w/ plasma proteins

Question 8

Delayed bleeding + easy bruising

Answer 8

Plasma proteins

Question 9

Inherited vascular system disorders

Answer 9

■ Hereditary hemorrhagic telangiectasia
■ Ehlers-Danlos syndrome
■ Marfan Syndrome
■ Osteogenesis imperfecta
■ Pseudoxanthoma elasticum

Question 10

Purpura due to decreased connective tissue

Answer 10

Senile Purpura
– Cushing Syndrome (Corticosteroid Therapy)
– Scurvy

Question 11

Purpura associated with protein disorders

Answer 11

Multiple myeloma
– Waldenstrom’s macroglobulinemia
– Lymphoproliferative disorder
■ Amyloidosis

Question 12

Purpura due to vasculitis

Answer 12

– Henoch-Schonlein Purpura
– Infections
– Drugs

Question 13

Miscellaneous causes of purpura

Answer 13

Mechanical Purpura
■ Artificially Induced Purpura
■ Easy Bruising Syndrome
■ Purpura Fulminans
■ Psychogenic Purpura

Question 14

Thrombocytopenia

Answer 14

SYMPTOM, not a disease
Most common cause for abnormal bleeding
symptons <50x109/L

Question 15

5 causes of thormbocytopenia

Answer 15

Increased destruction
Decreased production
increased splenic sequestration
dilutional thrombocytopenia
conditions with multiple mechanisms