A 46‑year‑old man was recently diagnosed with acute myeloid leukaemia (AML) after presenting with fatigue, recurrent infections and bruising. A bone marrow biopsy confirmed the diagnosis, and he was started on induction chemotherapy 2 days ago. He is now being reviewed on the ward because he is feeling increasingly unwell. He reports nausea, vomiting, muscle cramps, and reduced urine output over the past 12 hours. On examination, his heart rate is 110 bpm, blood pressure 92/60 mmHg, and he has mild peripheral oedema.