Jacob is a six-year-old boy brought in by his parents with progressively swollen, painful hands and wrists, with associated rash on the legs and abdominal pain over the past two days.

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<p>Jacob is a six-year-old boy brought in by his parents with progressively swollen, painful hands and wrists, with associated rash on the legs and abdominal pain over the past two days.</p><p>He had a self-limiting URTI a week ago, with rhinorrhoea and dry cough.</p><p>There is no associated fever, other joint involvement, headache, vomiting or neck stiffness.</p><p>Jacob is usually well, and immunisations are up to date, including meningococcal and influenza vaccines.</p><p>On examination, vital signs and hydration status are normal.</p><p>The only findings of note are non-pitting oedema of both hands and raised petechiae and patchy ecchymoses affecting the legs and feet (pictured).</p><p>Urinalysis is 1+ positive for blood.</p>

References on request from Dr Kate Kelso.