5. Circulatory Pathology

Question 1

What is edema?

Answer 1

Precense of excess fluid in the intracellular space.

Question 2

Describe transudate fluid.

Answer 2

Edema fluid with low protein content. Specific gravity

Question 3

Describe exudate fluid.

Answer 3

Edema fluid with high protein content and cells. Specific gravity >1.020.

Question 4

Describe the difference between active hyperemia versus passive hyperemia.

Answer 4

An excessive amount of blood in tissue or organ secondary to vadilation (active) or diminished venous outflow (passive).

Question 5

What is hemostasis?

Answer 5

Sequence of events leading to cessation of bleeding by the formation of stable fibrin-platelet hemostatic plug.

Question 6

What factor is on top of the extrinsic pathway?

Answer 6

Release of tissue factor from injured cells activates Factor VII.

Question 7

What factor is on top of the intrinsic pathway?

Answer 7

Exposure of thrombogenic subendothelial collagen activates Factor XII.

Question 8

Describe step 1 of platelet clotting.

Answer 8

Platelet adhesion: First von Willebrand factor (vWF) adheres to subendothelial collagen. Then platelets adhere to vWF glycoprotein Ib.

Question 9

Describe step 2 of platelet clotting.

Answer 9

Platelet activation. Platelets undergo a shape change and degranulation occurs. Platelets synthesis of thromboxane A2 and memebrane expression of the phospholipid complex, which is an important platform for the coagulation cascade.

Question 10

Describe step 3 of platelet clotting.

Answer 10

Platelet aggregation: Additional platelets are recruited from the blood stream. ADP and thromboxane A2 are potent mediators of aggregation. Platelets bind to each other by binding to fibrinogen using Gp IIb-IIIa.

Question 11

What causes Bernard-Soulier Syndrome?

Answer 11

It’s an autosomal recessive disease where deficiency of platelet Gp Ib leads to defective platelet adhesion (Step 1).

Question 12

What causes Glanzmann Thrombasthenia?

Answer 12

It’s an autosomal recessive disease where deficiency of Gp IIb-IIIa leads to defective platelet adhesion (Step 3).

Question 13

What is Immune thrombocytopenia purpura (ITP)?

Answer 13

When antiplatelet antiboides are made in the spleen against platelet antigens such as Gp IIb-IIIa and Gp Ib-IX; platelets are destroyed peripherally in the spleen by macrophages, which have Fc receptors that bind IgG-coated platelets.The acute form is seen in children following a viral infection; it is self-limited. The chronic kind is seen in women in their childbearing years, and maybe seen as the first manifestation of lupus.

Question 14

What is the treatment for Immune thrombocytopenia purpura (ITP)?

Answer 14

I. Corticosteroids, which decrease antibody production. II. Immunoglobulin therapy, which floods Fc receptors on splenic macrophages. III. Splenectomy, which removes the site of platelet desctruction and antibody production.

Question 15

What is Thrombocytopenic purpura (TTP)?

Answer 15

Widespread formation of platelet thrombi with scant fibrin (hyaline thrombi). No activation of the coagulation system.

Question 16

What are the pentad characteristic signs of Thrombocytopenic purpura (TTP)?

Answer 16

Fever, Thombocytopenia, Microangiopathic hemolytic anemia, Neurologic symptoms, Renal failure. [FTMNR]

Question 17

What is Hemolytic uremic syndrome (HUS)?

Answer 17

It has a similar clinical pentad as TTP, it occurs most often in children after a gastroenteritis with bloody diarrhea; verotoxin-producing E. coli 0157:H7.

Question 18

What does prothrombin time (PT) test for?

Answer 18

Test the extrinsic and common coagulation pathways. Factors VII, X, V, prothrombin, fibrinogen. [PT-E]

Question 19

What does partial thromboplastin time (PTT) test for?

Answer 19

Test the intrinsic and common coagulation pathways. Factors XII, XI,IX, VIII, X, V, prothrombin, fibrinogen.

Question 20

What does Thrombin time (TT) test for?

Answer 20

Adequate fibrinogen levels.

Question 21

What does Fibrin degradation products (FDP) test for?

Answer 21

Fibrinolytic system; increased with DIC.

Question 22

What causes hemophilia A?

Answer 22

AKA classic hemophelia, caused by the deficiency of factor XIII; X-linked recessive.

Question 23

What causes Hemophila B?

Answer 23

AKA Christmas disease, caused by the deficiency of factor IX; X-linked recessive.

Question 24

What factors of coagulation are affected in vitamin K deficiency?

Answer 24

Factors II, VII, IX, X. And protein C and S.

Question 25

What is von Willebrand disease?

Answer 25

Inherited bleeding disorder characterized by either a deficiency or qualitative defect in von Willebrand factor.

Question 26

Where is von Willebrand factor produced?

Answer 26

By endothelial cells and megakaryocytes.

Question 27

What is the treatment for type I (mild) cases of von Willebrand disease?

Answer 27

Desmopressin (an antidiuretic hormone (ADH) analog), which releases vWF from Weibel Palade bodies of endothelial cells.

Question 28

What is thrombosis?

Answer 28

Pathologic formation of an intravascular fibirn-platelet thombus.

Question 29

What does Thrombus have that blood clot doesn’t?

Answer 29

Blood clots lacks platelets and lines of Zahn and has no definite shape.

Question 30

What is an embolism?

Answer 30

Any intravascular mass that has been carried down the bloodstream from its site of origin, resulting in the occlusion of a vessel.

Question 31

What is Caisson diseaes?

Answer 31

A gas embolism caused by decompression sickness.

Question 32

What vessels make up the dual blood supply to the lungs?

Answer 32

Pulmonary artery and bornchial arteries.

Question 33

What is a paradoxical emboli?

Answer 33

Any venous embolus that gain access to the systemic circulation by crossing over from the right to the left side of the heart through a septal defect.

Question 34

Where do anemic infarcts like to strike?

Answer 34

AKA pale or white color infarcts, they like to strike in solid organs with a single blood supply such as kidney, spleen and heart.

Question 35

Where do hemorrhagic infarcts like to strike?

Answer 35

AKA red color infarcts, they like to strike organs with dual blood supply or collateral circulation such as the lungs or intestines. They also occur in venous occlusion like testicular torsion.

Question 36

What is a shock?

Answer 36

It is characterized by vascular collapse and widespread hypoperfusion of cells an tissue due to reduced blood volume, cardiac output, or vascular tone.

Question 37

What type of bacteria produces spetic shock?

Answer 37

Gram-negative.

Question 38

What is neurogenic shock and causes it?

Answer 38

Generalized vasodilation; anetheisia or brain/spinal cord injury.

Question 39

What happens in “shock lungs”?

Answer 39

Lungs undergo diffuse alveolar damage.

Question 40

What happens in “shock liver”?

Answer 40

Liver undergoes centrilobular necrosis.

Question 41

What is Waterhouse-Friderichsen Syndrome?

Answer 41

Commonly associated with meningococcal septic shock, it is a bilateral hemorrhagic infarction of the adrenals that causes acute adrenal insufficiency.