Immune Thrombocytopenic Purpura

Question 1

What is thrombocytopenia?

Answer 1

A platelet count of less than 150x10^9/L.

Question 2

What dictates the risk of bleeding in thrombocytopenia?

Answer 2

The severity

Question 3

What is considered to be severe thrombocytopenia?

Answer 3

Platelets <20 x 10^9/L

Question 4

What risk is severe thrombocytopenia associated with?

Answer 4

Spontaneous bleeding

Question 5

What is considered to be moderate thrombocytopenia?

Answer 5

Platelets 20-50 x 10^9/L

Question 6

What risk is moderate thrombocytopenia associated with?

Answer 6

Excess bleeding during operations or trauma

Question 7

Is there a risk of spontaneous bleeding with moderate thrombocytopenia?

Answer 7

Low risk

Question 8

What is considered to be mild thrombocytopenia?

Answer 8

50-150 x 10^9/L

Question 9

What risk is mild thrombocytopenia associated with?

Answer 9

Low risk of bleeding, unless there is a major operation or severe trauma

Question 10

What is the most common cause of thrombocytopenia in childhood?

Answer 10

Immune thrombocytopenic purpura

Question 11

What is the incidence of ITP in children?

Answer 11

About 4 in 100,000 / year

Question 12

What is ITP caused by?

Answer 12

Destruction of circulating platelets by anti-platelet IgG antibodies

Question 13

What might the reduced platelet count be associated with in ITP?

Answer 13

A compensatory increase in megakaryocytes in the bone marrow

Question 14

What are the risk factors for ITP?

Answer 14

• Female gender

- Recent viral infections

Question 15

Give 3 viral infections that ITP may follow?

Answer 15

• Mumps
• Measles
• Respiratory infection

Question 16

When do most children with ITP present?

Answer 16

Between the ages of 2 years and 10 years

Question 17

What does the onset of ITP often follow?

Answer 17

1-2 weeks after viral infection

Question 18

How long is the history of ITP?

Answer 18

In the majority of children, there is a short history of days or weeks

Question 19

What are the symptoms of ITP?

Answer 19

• Petechiae
• Purpura
• Superficial bruising
• Epistaxis and other mucosal bleeding

Question 20

What kind of diagnosis is ITP?

Answer 20

Diagnosis of exclusion

Question 21

What is the importance of ITP being a diagnosis of exclusion?

Answer 21

Careful attention must be paid to history, clinical features, and a blood film to ensure a more sinister diagnosis is not missed

Question 22

What are the differential diagnoses of ITP?

Answer 22

• Congenital conditions
• Acute leukaemia or aplastic anaemia
• SLE

Question 23

What congenital conditions are differentials for ITP?

Answer 23

• Wiskott-Aldrich

- Bernard-Soulier syndrome

Question 24

Why is ITP not always concerning?

Answer 24

In about 80% of children, the disease is acute, benign, and self limiting, usually remitting spontaneously within 6-8 weeks

Question 25

Where can most children with ITP be managed?

Answer 25

At home, without need for hospital admission

Question 26

Why is treatment for ITP controversial?

Answer 26

Because most children do not need any therapy, even if the platelet count is less than 10 x 10^9/L

Question 27

When should treatment for ITP be given?

Answer 27

If there is any evidence of major bleeding

Question 28

Give two examples of sources of major bleeding in ITP?

Answer 28

- Intracranial | - Gastrointestinal

Question 29

What are the treatment options for ITP?

Answer 29

- Oral prednisolone - IV anti-D - IV immunoglobulins - Platelet transfusions

Question 30

What is the problem with treatments for ITP?

Answer 30

All the treatments have serious side effects

Question 31

What are platelet transfusions used for in ITP?

Answer 31

Reserved for life-threatening haemorrhage

Question 32

Why are platelet transfusions reserved for life threatening haemorrhage in ITP?

Answer 32

As they only raise platelet count for a few hours

Question 33

What general measures should be taken when a child with ITP has a very low platelet count?

Answer 33

- Parent needs immediate 24-hour access to hospital | - Child should avoid trauma, e.g. contact sports

Question 34

What is chronic ITP?

Answer 34

When the platelet count remains low for 3 months after diagnosis

Question 35

What % of children with ITP will have chronic ITP?

Answer 35

20%

Question 36

What is the treatment for chronic ITP in the majority of children?

Answer 36

Mainly supportive

Question 37

When is drug treatment offered to children with chronic ITP?

Answer 37

Children with persistent bleeding that affects daily activity or impairs quality of life

Question 38

Is it common for children with chronic ITP to have significant bleeding?

Answer 38

No, it is rare

Question 39

What treatments are available for chronic ITP?

Answer 39

- Rituximab - Thrombopoietic growth factors - Splenectomy

Question 40

Give an example of a complication of ITP

Answer 40

Intracranial bleeding