Osteomyelitis and discitis — branching viva

Emergency department: a three-year-old boy with three days of fever and refusal to walk, holding his left leg still, with exquisite tenderness over the distal tibial metaphysis and a C-reactive protein of 95 milligrams per litre. The examiner asks: describe your diagnostic approach, give your likely diagnosis and its pathophysiological basis, and outline the management — then branches to the role of magnetic resonance imaging, the empirical antibiotic selection and the Kingella kingae consideration, the intravenous-to-oral switch criteria, the child who fails to improve at 48 to 72 hours, and finally to a two-year-old girl who refuses to sit or walk that reframes the diagnosis as discitis.