Long-Term Incidence and Risks for Recurrent Stones Following Contemporary Management of Upper Tract Calculi in Patients with a Urinary Diversion

Abstract

Purpose The long-term rate of stone recurrence following contemporary minimally invasive management of calculi was determined in patients with urinary diversion and to identify specific risk factors for these recurrences. Materials and Methods We followed for a minimum of 12 months 25 patients (29 renal units) with upper tract calculi associated with urinary diversion, and treated with extracorporeal shock wave lithotripsy and/or percutaneous nephrostolithotomy. The risk of recurrent stones at 5 years was determined by a Kaplan-Meier estimate, while potential risk factors for recurrence were analyzed using a log-rank comparison. Results Stones recurred in 8 patients (32 percent) 18 to 61 months (mean 27.0) after treatment. The risk of new stone formation after 5 years was estimated to be 63.3 percent and was significantly greater in patients with recurrent bacteriuria after treatment. Neither stone history, type of procedure used, stone composition nor radiographic status of completion of treatment significantly influenced this risk. Conclusions Contemporary management of upper tract calculi in patients with a urinary diversion is associated with a high recurrence rate, especially among those with recurrent bacteriuria, regardless of whether the patient is initially rendered stone-free. Continued close surveillance and antibiotic prophylaxis seem to be essential in this high risk patient population.