In a child presenting with features consistent with a diagnosis of juvenile idiopathic arthritis, what clinical features or laboratory findings (at presentation) predict a diagnosis of acute lymphoblastic leukaemia?

摘要

A 10-year-old boy presented with joint pain and arthritis with joint effusions and decreased range of motion in the right wrist, both elbows, and right ankle. Initial investigations showed a normal full blood count (FBC) and film (haemoglobin 124 g/L, white cell count (WCC) 8.1 x 10~9/L, platelets 378 x 10~9/L) with raised inflammatory markers (ESR 78 mm/h, CRP 40mg/L). Neither antinuclear antibodies nor human leukocyte antigen B-27 were present. X-rays demonstrated a right ankle effusion but were otherwise normal.