Emergency and Toxicologymiddle twist
A 58-year-old woman presents with two days of right loin pain radiating to the groin, associated with shaking chills. Her temperature is 38.9°C, pulse 118/min and blood pressure 96/58 mmHg. Non-contrast CT of the urinary tract shows a 9 mm calculus at the right pelviureteric junction with moderate hydronephrosis; the left kidney is normal. Blood tests show a white cell count of 18.2 x 10^9/L (4.0-11.0) and creatinine 152 micromol/L (45-90). Intravenous fluid resuscitation, analgesia and intravenous antibiotics have been commenced. Which one of the following is the most appropriate next step in management?