Thrombocytopenia

Question 1

Thrombotic microangiopathy due to platelet activation by exotoxins. These toxins then cause direct damage to the endothelium.

Answer 1

Hemolytic Uremic Syndrome

Question 2

What exotoxin is commonly responsible for Hemolytic Uremic Syndrome?

Answer 2

Shiga Toxin
(E.Coli O157:H7)

Question 3

What is the triad of symptoms commonly seen in HUS?

Answer 3

Thrombocytopenia
Microangiopathic Hemolytic Anemia
Renal Dysfunction (uremia)

Question 4

What type of patient is typically seen presenting with HUS?

Answer 4

Children (especially under 5) with a recent gastroenteritis

Question 5

What is the mainstay of treatment for HUS?

Answer 5

Supportive Therapy
Plasma Exchange
Aggressive Antibiotic Therapy

Question 6

Thrombotic microangiopathic hemolytic anemia resulting from the decreased activity of protease ADAMTS-13

Answer 6

Thrombotic Thrombocytopenic Purpura (TTP)

Question 7

An ADAMTS-13 deficiency which causes Thrombotic Thrombocytopenic Purpura (TTP) leads to what?

Answer 7

Large von Willebrand Factor multimers that cause small vessel thrombosis due to platelet adhesion and aggregation.

Question 8

What is the primary etiology of Thrombotic Thrombocytopenic Purpura (TTP)

Answer 8

Autoimmune
(antibodies against ADAMTS-13)

Question 9

What is the classical Pentad presentation of Thrombotic Thrombocytopenic Purpura (TTP)

Answer 9

Thrombocytopenia
Microangiopathic Hemolytic Anemia (MAHA)
Neurologic Symptoms
Fever
Renal Failure

Question 10

What medications can cause Thrombotic Thrombocytopenic Purpura (TTP)

Answer 10

Quinidine
Ticlopidine
Tacrolimus
Cyclosporine
Clopidogrel

Question 11

What is the mainstay of treatment for Thrombotic Thrombocytopenic Purpura (TTP)

Answer 11

Plasmapheresis
(Plasma Exchange)

Question 12

Autoimmune condition where pathogenic antibodies bind to platelets and dispose of them.

Answer 12

Idiopathic Thrombocytopenic Purpura

Question 13

What two diseases may lead to Idiopathic Thrombocytopenic Purpura?

Answer 13

HIV
Hepatitis C

Question 14

What are some of the symptoms of Idiopathic Thrombocytopenic Purpura?

Answer 14

WET BLEEDING
- excessive mucocutaneous bleeding
- gingival bleeding
- epistaxis
- hematuria
- melena
- excessive vaginal bleeding

Question 15

What are some signs you’d expect to see in a patient with Idiopathic Thrombocytopenic Purpura?

Answer 15

Normal CBC (except Thrombocytopenia)
Large Platelets
No Schistocytes
No Splenomegaly