• Septic shock with associated ureteric obstruction/hydronephrosis with suspicion or pyonephrosis
• Fever and features of renal colic

As soon as possible

• Hydronephrosis/ureteric obstruction on imaging +/- AKI OR persisting fever after 72 h on appropriate antibiotic therapy
• Renal abscess detected on renal tract imaging
• Emphysematous cystitis or pyelonephritis detected on imaging
• Non-obstructing stones found on imaging
• Acute on chronic retention requiring catheterization

Routine follow-up through clinic

• Unexplained recurrent urinary tract infection
• Recurrent urinary tract infections in children