ITP

Question 1

What causes ITP

Answer 1

Unknown

Thought to be viral or other immune phenomenon

Question 2

What is the peak age for ITP

Answer 2

2-5yo

Question 3

What is the natural history of ITP

Answer 3

75-80% resolve in 6mo
Some of the rest resolve by 12mo
If persistent over 12mo = chronic ITP

Question 4

How many ITP present with serious bleeding from nose, mouth, GIT

Answer 4

3%

Question 5

How many present with ICH?

Answer 5

0.17-0.6%

Question 6

What are red flags for an alternative diagnosis to ITP?

Answer 6

History

• constitutional symptoms
• bone pain
• recurrent thrombocytopenia
• poor treatment response

P/E

• LAN
• Hepatomegaly
• Splenomegaly
• Appears unwell
• Signs of chronic disease

Investigations

• low Hgb
• High MCV
• AbN WBC and or neutrophil count
• AbN morphology on smear

Question 7

What is the typical platelet count in ITP

Answer 7

<100 x 10^9

Most cases are <20

Question 8

What are secondary causes of ITP

Answer 8

Drug-induced 
SLE
Infections
Immune-deficiencies 
Malignancies

Question 9

What are management options for ITP

Answer 9

Observation
Steroids
IVIG
anti-D Ig (if Rh+)

Question 10

What is the goal of ITP treatment

Answer 10

Having a platelet count associated with adequate Hemostasis NOT targeting a number

Question 11

How many cases of ITP present with petechiae and or bruising

Answer 11

77%

Question 12

What is the recommendation for ITP without active bleeding

Answer 12

Observation - 1st line
Steroids or IVIG - 2nd line

Consider bleeding risk, logistics (distance from hospital), social issues
**Do shared decision making

Question 13

What is the recommendation for ITP with moderate bleeding

Answer 13

Active therapy

• IVIG 1g/kg
• Steroids

Question 14

Why is anti-D Ig not considered 1st line therapy

Answer 14

Can only be used in Rh+ patients

has rare but serious adverse effects

Question 15

What is the recommendation for ITP with severe bleeding

Answer 15

Hospitalisation
IV steroids and IVIG
Consider TXA

Question 16

When should a platelet transfusion be considered

Answer 16

Only if acute life-threatening bleeds or if needs immediate surgery

Question 17

What is the dose of TXA recommended?

Answer 17

25mg/kg/dose TID-QID

Max 1500mg per dose

Question 18

What is the goal of active therapy in ITP

Answer 18

Increase platelets to achieve HDS

Question 19

What defines a relapse in ITP? And how is it treated?

Answer 19

Platelets falling to <20 within 2-6wk
Occurs in 1/3 of patients
Retreat based on similar criteria as initial presentation

Question 20

What counselling to give to a new ITP patient

Answer 20

Anticipatory guidance
Regular follow up until platelets have recovered
Avoid contact sports or activities until platelets recovered
Avoid anti-platelets medications

Question 21

Define

1. Mild bleeding
2. Moderate bleeding
3. Severe bleeding

Answer 21

1. No bleeding, or petechiae, mild epistaxis - 77% cases
2. More severe skin manifestation, muscular lesions, troublesome epistaxis or menorrhagia - 20%
3. Bleeding episodes requiring hospital admission - epistaxis, melena, menorrhagia, ICH - 3%

Question 22

What is the dose of steroids? What are its advantages and disadvantages

Answer 22

Prednisone 4mg/kg/d PO BID-QIDx 4d
Prednisone 2mg/kg/d PO x 1-2wk + taper

Advantage: outpatient, no IV, inexpensive, works in 72-88%, platelets increase in 48h

Disadvantages: increased appetite, weight, mood changes, HTN, poor tastes, gastritis

Question 23

What is the dose of IVIG? What are its advantages and disadvantages

Answer 23

• 0.8-1.0mg/kg/dose x 1
• advantages: works in >80%, platelets increased by 24, peak at 2-7d, rapid increase
• disadvantage: hospitalisation and IV required, more expensive, can have hemolysis, rash, fever, N/V, HA/aseptic meningitis