OSCE — pruritus without primary rash: systemic work-up and targeted management

Brief (to candidate)

A 58-year-old has severe generalised itch for 3 months with only excoriations. No primary eczematous plaques. He takes multiple drugs; exam shows no jaundice yet. You have 8 minutes to take a focused history, plan investigations, and outline initial management.

Candidate instructions

1. Define pruritus sine materia / itch without primary rash vs secondary excoriations.
2. Screen systemic causes with history and first-line labs.
3. Recognise polycythaemia vera and haematologic red flags (aquagenic itch).
4. Avoid defaulting solely to sedating antihistamines.
5. Give skin barrier care plus cause-directed therapy principles.

Examiner checklist (mark each domain / 10)

Model key actions

• Treat itch without primary rash as a systemic symptom complex and order core labs.^[2]
• Ask specifically for aquagenic itch and pursue polycythaemia when suggested.^[1]
• Combine emollient care with cause-directed therapy rather than endless sedating antihistamines alone.^[3]

Common errors

• Diagnosing “eczema” without primary lesions and giving only steroids.
• Missing scabies by not re-examining finger webs/genitalia.
• Ignoring FBC abnormalities / aquagenic itch.
• Chronic first-generation antihistamines as sole plan.
• No safety-net for B symptoms/malignancy.