4th May 2024

A 22-year-old man presents to the clinic with general malaise, recurring infections, and unexplained bruises.

A 22-year-old man presents to the clinic with general malaise, recurring infections, and unexplained bruises. He has no significant past medical history. Physical examination reveals mild splenomegaly and petechiae. Laboratory investigations show:

White cell count: 105 x 10⁹/L (4.0–11.0)

Haemoglobin: 95 g/L (130–170)

Platelets: 45 x 10⁹/L (150–400)

Bone marrow biopsy confirms the diagnosis of acute lymphoblastic leukaemia (ALL) without central nervous system involvement. His leukaemic burden is high, with a white blood cell count significantly above the reference range.

Which is the most appropriate initial management step?