Immune Thrombocytopenia (ITP) in Adults

Key points

• 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.
• DISTINGUISH THE TWO PATTERNS — this is a common exam trap. ACUTE (childhood) ITP: more common in children, equal sex incidence, often follows an infection or vaccination, and usually runs a self-limiting course over 1–2 weeks.
• CHRONIC (adult) ITP: typically an insidious onset in adults, more common in women, and does NOT usually remit spontaneously — it tends to run a chronic course and is the pattern relevant to adult management (see the ITP: Investigation and Management chapter). Chronic ITP