Immune Thrombocytopenic Purpura/ Gest Thrombocytopenia

Question 1

What causes ITP?

Answer 1

Primary ITP is defined as an acquired immune-mediated disorder characterized by isolated thrombocytopenia in the absence of any obvious initiating or underlying cause of thrombocytopenia (a platelet count of less than 100 × 109/L)

Question 2

How is ITP diagnosed?

Answer 2

There are no pathognomonic signs, symptoms, or diagnostic tests for ITP, making it a diagnosis of exclusion.

Question 3

In a pregnant patient with thrombocytopenia, what is your differential diagnosis?

Answer 3

• Lab error
• Pseudothrombocytopenia (platelet clumping)
• Gestational
• Immune mediated
• ALF
• HUS
• TTP
• HELLP
• DIC
• Preeclampsia
• Lupus/APS
• HIV, Hep C, CMV, H. pylori
• Drug induced

Question 4

What work-up do you do for pregnant patient with thrombocytopenia in pregnancy?

Answer 4

• Physical examination
• Assess Vitals
• Obtain CBC with peripheral smear

Question 5

What is gestational thrombocytopenia?

Answer 5

Thrombocytopenia due to hemodilution and enhanced clearance.
5 key characteristics of gestational thrombocytopenia:

1) onset can occur at any point in pregnancy (most common on the mid-second to third trimester, with most cases having a platelet count more than 75)
2) asymptomatic with no history of bleeding
3) no history of thrombocytopenia outside of pregnancy
4) platelet counts usually return to normal within 1–2 months after giving birth
5) the incidence of fetal or neonatal thrombocytopenia in the setting of gestational thrombocytopenia is low.

Question 6

How can gestational thrombocytopenia be separated from ITP?

Answer 6

ITP:

• Onset, persistence in and out of pregnancy
• can be symptomatic
• associated with neonatal thrombocytopenia

gestational:
- Onset in pregnancy
- asymptomatic
- not associated with neonatal thrombocytopenia
- platelet count usually above 75

Question 7

What are complications of ITP in pregnancy?

Answer 7

• Bleeding
• Fetal and neonatal thrombocytopenia
• Need for transfusion

Question 8

What are treatment options for ITP in pregnancy?

Answer 8

• Steroids (Prednisone 0.5–2 mg/kg daily, see response in 2 weeks)
• IVIG (1mg/kg x 1 dose, can be repeated, see response in 3 days)
• Platelet transfusion (infused with intravenous high-dose corticosteroids or IVIG ranging from every 30 minutes to 8 hours)
• Splenectomy (avoid in pregnancy)

Question 9

When is treatment of ITP warranted?

Answer 9

• Platelet count less than 30,000 with symptomatic bleeding
• Platelet count less than 50,000 with impending surgical procedure
• Platelet count less than 70,000 with neuraxial anesthesia

Question 10

What are the fetal risks if patient has ITP?

Answer 10

Fetal thrombocytopenia with hemorrhage (risk is less than 1%).

Question 11

What are treatment options for gestational thrombocytopenia?

Answer 11

• Delivery if at term

- Platelet transfusion

Question 12

When is treatment of gestational thrombocytopenia warranted?

Answer 12

• Platelet count less than 50,000 with impending surgical procedure
• Platelet count less than 70,000 with neuraxial anesthesia

Question 13

Below what platelet threshold is neuraxial anesthesia no longer allowed?

Answer 13

Platelet count less than 70,000

Question 14

What are the risks of neuraxial anesthesia in thrombocytopenic patient?

Answer 14

epidural hematoma

Question 15

Define mild, moderate and severe thrombocytopenia:

Answer 15

Mild - 100-150
Moderate - 50-100
Severe - <50