FFinalistSouthampton · 2027
Child health
AKT · Child health/Oncology

Immune thrombocytopenia (ITP)

Immune-mediated platelet destruction (often post-viral)

Overview

Isolated thrombocytopenia from immune platelet destruction, typically 1–2 weeks after a viral infection in an otherwise well young child. Usually self-limiting; the task is to exclude sinister causes of low platelets.

Recognise

  • Sudden bruising, petechiae, mucosal bleeding (epistaxis, gums) in a WELL child
  • Isolated LOW platelets — Hb and white cells normal
  • No hepatosplenomegaly or lymphadenopathy (those suggest leukaemia)

Red flags

  • Significant mucosal/GI bleeding; suspected intracranial bleed (severe headache/neuro signs) — rare but serious

Differentials & how to tell them apart

Acute lymphoblastic leukaemia (ALL)pancytopenia, blasts, hepatosplenomegaly/lymphadenopathy, bone pain — NOT isolated low platelets
Henoch-Schönlein purpura (IgA vasculitis)palpable purpura + arthralgia/abdo/renal, NORMAL platelets
Meningococcal sepsisunwell, spreading purpura — emergency
Idiopathic aplastic anaemiapancytopenia

Investigations

FBC + blood film: isolated thrombocytopenia, otherwise normal; the film excludes blasts. Bone marrow only if atypical features or before steroids in doubt.

Management

Watchful waiting in the well child; treat bleeding, not the number

  1. 1If the child is well with only skin signs: watchful waiting + safety-net (avoid contact sport, NSAIDs, aspirin).Gate: Treatment (steroids/IVIG) is for significant BLEEDING, not for a low platelet count alone
  2. 2Significant bleeding: prednisolone or IVIG (or anti-D). Persistent >12 months = chronic ITP → haematology.
Watchful waiting — most children — platelets recover spontaneously
Prednisolone / IVIG / anti-D — only for significant bleeding (not for the count alone)

Key points

Isolated thrombocytopenia in a well child = ITP; pancytopenia or organomegaly/bone pain shifts you to leukaemia — exactly the discrimination the exam wants.

Monitor & prognosis

Platelet recovery (usually weeks); bleeding signs.

~80% of childhood ITP resolves spontaneously within 6 months.

Source: NICE CKS; British Society for Haematology