Immune thrombocytopaenia purpura (ITP) Flashcards
What is Immune (or idiopathic) thrombocytopenic purpura (ITP)?
ITP is an immune-mediated reduction in the platelet count where antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex. It is a type II hypersensitivity reaction.
How does ITP in children typically present compared to adults?
ITP in children is more acute and may follow an infection or vaccination.
What are the main features of ITP in children?
The main features are bruising, petechial or purpuric rash, and less commonly bleeding which typically presents as epistaxis or gingival bleeding.
What does a full blood count show in a child with ITP?
A full blood count shows isolated thrombocytopenia.
When is a bone marrow examination required in ITP?
A bone marrow examination is required if there are atypical features such as lymph node enlargement/splenomegaly, high/low white cells, or failure to resolve/respond to treatment.
What is the usual treatment for ITP in children?
Usually, no treatment is required as ITP resolves in around 80% of children within 6 months, with or without treatment.
What advice should be given to children with ITP regarding activities?
Children with ITP should avoid activities that may result in trauma, such as team sports.
What are the treatment options if the platelet count is very low (< 10 * 109/L) or there is significant bleeding in a child with ITP?
Treatment options include oral/IV corticosteroids, IV immunoglobulins, and platelet transfusions in emergencies.
Why are platelet transfusions only a temporary measure in ITP?
Platelet transfusions are temporary because the platelets are soon destroyed by the circulating antibodies.
summarise ITP
Immune thrombocytopenia (ITP) in children
Immune (or idiopathic) thrombocytopenic purpura (ITP) is an immune-mediated reduction in the platelet count. Antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex. It is an example of a type II hypersensitivity reaction.
ITP in children is typically more acute than in adults and may follow an infection or vaccination.
Features
bruising
petechial or purpuric rash
bleeding is less common and typically presents as epistaxis or gingival bleeding
Investigation
full blood count
should demonstrate an isolated thrombocytopenia
blood film
bone marrow examinations is only required if there are atypical features e.g.
lymph node enlargement/splenomegaly, high/low white cells
failure to resolve/respond to treatment
Management
usually, no treatment is required
ITP resolves in around 80% of children with 6 months, with or without treatment
advice to avoid activities that may result in trauma (e.g. team sports)
other options may be indicated if the platelet count is very low (e.g. < 10 * 109/L) or there is significant bleeding. Options include:
oral/IV corticosteroid
IV immunoglobulins
platelet transfusions can be used in an emergency (e.g. active bleeding) but are only a temporary measure as they are soon destroyed by the circulating antibodies
A 10-year-old boy presents to the emergency department with his mother who is very concerned as she has noticed a non-blanching petechial rash on his arms and legs. The child has had a recent cold but today his observations are normal and he appears well otherwise.
What is the most likely diagnosis?
Haemolytic uraemic syndrome (HUS)
Henoch-Schonlein purpura (HSP)
Immune thrombocytopaenic purpura (ITP)
Meningitis
Non accidental injury
Immune thrombocytopaenic purpura
ITP is a differential in any child presenting with petechiae and no fever
Important for meLess important
HUS is incorrect - HUS is associated with a triad of microangiopathic haemolytic uraemia, acute kidney injury and thrombocytopenia. The symptoms are typically bloody diarrhoea, abdominal pain, fever and vomiting, and the history usually includes exposure to farm animals. The child in the question hasn’t experienced these symptoms so this diagnosis is unlikely.
HSP is incorrect - Features of HSP are typically a non-blanching rash affecting the legs and buttocks, arthralgia and abdominal pain. This child has presented with a non-blanching rash but not in the distribution of HSP and has not experienced any other symptoms of HSP. The child has presented with a typical history of ITP so a diagnosis of ITP is more likely.
ITP is correct - ITP is correct as it is a differential in any child presenting with petechiae and no fever and is usually preceded by a viral illness. We need blood results to confirm the diagnosis but these typically present with isolated thrombocytopenia and this low platelet count causes the classic petechial rash.
Meningitis is incorrect - Meningitis is a top differential for anyone presenting with a petechial rash but this child is well and has no fever so this diagnosis is unlikely.
Non-accidental injury is incorrect - NAI is an essential differential for any petechial rash but this rash is a good description of ITP. The question stem does not give any red flags for non-accidental injury but this should still be considered in practice.
A 10-year-old boy presents to the emergency department with his mother who is very concerned as she has noticed a non-blanching petechial rash on his arms and legs. The child has had a recent cold but today his observations are normal and he appears well otherwise.
What is the most likely diagnosis?
Haemolytic uraemic syndrome (HUS)
Henoch-Schonlein purpura (HSP)
Immune thrombocytopaenic purpura (ITP)
Meningitis
Non accidental injury
Immune thrombocytopaenic purpura (ITP)
ITP is a differential in any child presenting with petechiae and no fever
HUS is incorrect - HUS is associated with a triad of microangiopathic haemolytic uraemia, acute kidney injury and thrombocytopenia. The symptoms are typically bloody diarrhoea, abdominal pain, fever and vomiting, and the history usually includes exposure to farm animals. The child in the question hasn’t experienced these symptoms so this diagnosis is unlikely.
HSP is incorrect - Features of HSP are typically a non-blanching rash affecting the legs and buttocks, arthralgia and abdominal pain. This child has presented with a non-blanching rash but not in the distribution of HSP and has not experienced any other symptoms of HSP. The child has presented with a typical history of ITP so a diagnosis of ITP is more likely.
ITP is correct - ITP is correct as it is a differential in any child presenting with petechiae and no fever and is usually preceded by a viral illness. We need blood results to confirm the diagnosis but these typically present with isolated thrombocytopenia and this low platelet count causes the classic petechial rash.
Meningitis is incorrect - Meningitis is a top differential for anyone presenting with a petechial rash but this child is well and has no fever so this diagnosis is unlikely.
Non-accidental injury is incorrect - NAI is an essential differential for any petechial rash but this rash is a good description of ITP. The question stem does not give any red flags for non-accidental injury but this should still be considered in practice.
A 6-year-old boy presents to the emergency department with a rash. His parents deny any trauma and are not known to social services. He has had a recent coryzal illness which resolved without intervention.
The child has no past medical history. He was born at term via vaginal delivery. He has reached all developmental milestones and is up-to-date with vaccinations.
On examination, there is a petechial rash on the child’s legs. He looks otherwise well with no other signs of bleeding.
His blood tests:
Hb 145 g/L Male: (135-180)
Platelets 29 * 109/L (150 - 400)
WBC 7.2 * 109/L (4.0 - 11.0)
What is the indicated management?
IV corticosteroid
IV immunoglobulin
None
Oral corticosteroid
Platelet transfusion
None
Children with immune thrombocytopenia: no treatment is usually required for children with petechia/purpura only and no significant bleeding
None is the correct answer as there are no signs of bleeding on examination. This child does not require any further medical management for his idiopathic thrombocytopenic purpura (ITP) as the platelet count is not less than 10 and no active bleeding, so in this well, patient cohort 80% have full resolution of the ITP with or without treatment. Advice to avoid any trauma is crucial.
Oral corticosteroid is an incorrect answer because this is not indicated for immunosuppression in a child who is not actively bleeding and the platelet count will recover in the majority of cases.
IV corticosteroid is incorrect as per the oral corticosteroid explanation the child will most likely recover spontaneously without requiring the risks of using non-specific immunosuppressants.
IV immunoglobulin is an incorrect option. This is because the child is well, with no signs of active or previous bleeding and the platelet count is sufficient.
Platelet transfusion is incorrect as this is only indicated with active bleeding, and has limited efficacy in ITP as the circulating antibodies quickly destroy the transfused platelets.
