ITP Flashcards
What causes ITP
Unknown
Thought to be viral or other immune phenomenon
What is the peak age for ITP
2-5yo
What is the natural history of ITP
75-80% resolve in 6mo
Some of the rest resolve by 12mo
If persistent over 12mo = chronic ITP
How many ITP present with serious bleeding from nose, mouth, GIT
3%
How many present with ICH?
0.17-0.6%
What are red flags for an alternative diagnosis to ITP?
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
What is the typical platelet count in ITP
<100 x 10^9
Most cases are <20
What are secondary causes of ITP
Drug-induced SLE Infections Immune-deficiencies Malignancies
What are management options for ITP
Observation
Steroids
IVIG
anti-D Ig (if Rh+)
What is the goal of ITP treatment
Having a platelet count associated with adequate Hemostasis NOT targeting a number
How many cases of ITP present with petechiae and or bruising
77%
What is the recommendation for ITP without active bleeding
Observation - 1st line
Steroids or IVIG - 2nd line
Consider bleeding risk, logistics (distance from hospital), social issues
**Do shared decision making
What is the recommendation for ITP with moderate bleeding
Active therapy
- IVIG 1g/kg
- Steroids
Why is anti-D Ig not considered 1st line therapy
Can only be used in Rh+ patients
has rare but serious adverse effects
What is the recommendation for ITP with severe bleeding
Hospitalisation
IV steroids and IVIG
Consider TXA
When should a platelet transfusion be considered
Only if acute life-threatening bleeds or if needs immediate surgery
What is the dose of TXA recommended?
25mg/kg/dose TID-QID
Max 1500mg per dose
What is the goal of active therapy in ITP
Increase platelets to achieve HDS
What defines a relapse in ITP? And how is it treated?
Platelets falling to <20 within 2-6wk
Occurs in 1/3 of patients
Retreat based on similar criteria as initial presentation
What counselling to give to a new ITP patient
Anticipatory guidance
Regular follow up until platelets have recovered
Avoid contact sports or activities until platelets recovered
Avoid anti-platelets medications
Define
- Mild bleeding
- Moderate bleeding
- Severe bleeding
- No bleeding, or petechiae, mild epistaxis - 77% cases
- More severe skin manifestation, muscular lesions, troublesome epistaxis or menorrhagia - 20%
- Bleeding episodes requiring hospital admission - epistaxis, melena, menorrhagia, ICH - 3%
What is the dose of steroids? What are its advantages and disadvantages
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
What is the dose of IVIG? What are its advantages and disadvantages
- 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
