Optimising management strategies for ultrasound detected renal stones: The role of advice and guidance

Background: Renal stones are a common finding on ultrasound in primary care, often detected incidentally or during investigation for abdominal pain. Patients are frequently then referred to secondary care for further investigations. However, small (<5 mm) or asymptomatic stones may be safely managed in primary care without specialist intervention. As computed tomography of the kidneys, ureters and bladder remains the gold standard for diagnosing urinary tract stones, general practitioners within our Trust are advised by a consultant-led triage team to arrange computed tomography of the kidneys, ureters and bladder. This is prior to being accepted to secondary care in order to try and improve the efficiency of the patient pathway. Objectives: This study aimed to: (1) assess the accuracy of ultrasound in detecting clinically significant renal calculi (⩾5 mm) compared to computed tomography of the kidneys, ureters and bladder, (2) determine the proportion of patients who could be managed without specialist clinical review and (3) evaluate the impact of triage team advice and guidance on patient pathways. Methods: A retrospective review of 100 patients referred by general practitioners for computed tomography of the kidneys, ureters and bladder following ultrasound and advice and guidance input was conducted over 12 months (December 2023–November 2024). Data included stone size, number, laterality and timing between scans. Patients were included if they had had a prior ultrasound and were referred via urology e-consult. Results: Computed tomography findings differed from ultrasound in 85% of cases. Clinically significant stones (⩾5 mm) were confirmed in 47% of computed tomographies. Ultrasound overestimated stone size in 53% and underestimated it in 21%. Ultrasound overestimated stone number in 17% and underestimated it in 34%. The advice and guidance pathway reduced unnecessary clinic referrals by 53%, improving patient experience and service capacity. Conclusion: Ultrasound demonstrated limited accuracy in assessing renal calculi in this patient cohort. Early computed tomography of the kidneys, ureters and bladder, guided by advice and guidance, improves diagnostic precision, optimises patient flow and enhances resource allocation.