Immune thrombocytopenia purpura (ITP) Flashcards
What is Immune thrombocytopenia purpura?
Syndrome characterised by immune destruction of platelets resulting in bruising or a bleeding tendency
Describe the aetiology of Immune thrombocytopenia purpura
Often IDIOPATHIC
Autoantibodies bind to platelet membrane proteins (e.g. GlpIIb/IIIa )+ destroy
What are the differentials for Immune thrombocytopenia purpura?
Infections (HIV, Hep C, H.Pylori)
AI diseases (e.g. SLE, thyroid disease)
Malignancies
Drugs (e.g. quinine)
List 3 risk factors for Immune thrombocytopenia purpura
Women of childbearing age
< 10yrs
> 65yrs
Describe the epidemiology of Immune thrombocytopenia purpura
Acute ITP: CHILDREN
Chronic ITP: ADULTS
F > M
List 4 symptoms of Immune thrombocytopenia purpura
MEME Mucosal bleeding e.g. bleeding gums Easy bruising Menorrhagia Epistaxis
What is ABSENT in Immune thrombocytopenia purpura?
Systemic symptoms:
Weight loss
Fever
Splenomegaly/ hepatomegaly/ lymphadenopathy
Give 2 signs of Immune thrombocytopenia purpura
Visible petechiae (most common on lower limbs) Bruises
What conditions must be excluded before diagnosing Immune thrombocytopenia purpura?
Myelodysplasia
Acute leukaemia
Marrow infiltration
What is seen on bloods in Immune thrombocytopenia purpura?
FBC: low platelets (<100): ISOLATED LOW PLTS
Clotting screen: normal PT, APTT + fibrinogen
Autoantibodies (e.g. antiplatelet antibody)
Why perform a blood film in suspected Immune thrombocytopenia purpura?
To rule out pseudothrombocytopaenia (which is caused by platelets clumping together + giving falsely low counts)
What other investigations are performed to exclude other diagnoses in suspected Immune thrombocytopenia purpura?
HIV/ HepC serology: -ve
TFTs (as hyper-/hypothyroidism can cause thrombocytopenia)
Pregnancy test
Bone Marrow biopsy
Who is more commonly affected by acute or chronic ITP?
Acute: After viral infection in children
Chronic: Adults
