Removing asymptomatic kidney stones during symptomatic stone removal surgery may result in lower risk of recurrence

A small study has found that people have a lower chance of future kidney stone problems if smaller, asymptomatic kidney stones are also removed during surgery to remove larger, symptomatic ones. Kidney stones are hard, pebble-like structures that form in the kidneys when a person has high levels of certain minerals in their urine. Depending on their location and size, some kidney stones may be able to pass through the urinary tract without treatment. Others, however, can cause complications including severe pain, bloody urine, and urinary tract infections. Asymptomatic kidney stones are more common than and are often found alongside of symptomatic stones. There are conflicting views about the impact of leaving these asymptomatic stones behind during removal of symptomatic ones, and current guidelines leave it to doctors and patients to decide whether to remove them or simply monitor for recurrence of symptoms.

One approach to treatment for people with symptomatic kidney stones is endoscopic surgery, during which a small, thin camera is inserted into the urethra to find and remove any stones. In a recent study, 73 people undergoing endoscopic surgery for removal of symptomatic kidney stones were randomized either to have their asymptomatic stones removed during the procedure (treatment group) or not (control group). Both groups were then monitored up to 5 years post-surgery for recurrence in the form of an emergency room visit for stones on the same side as the removal, subsequent stone removal surgery on the same side, or visualized growth of an asymptomatic stone via a CT scan. The researchers found that recurrence occurred substantially more often in the control group than in the treatment group—63 percent compared to 16 percent—and that the time to recurrence was an average of 697 days longer in the treatment group than in the control group. Removal of asymptomatic stones did increase the duration of the surgery time, usually by less than 30 minutes.

The findings from this study suggest that removing both symptomatic and asymptomatic kidney stones during endoscopic surgery may reduce the likelihood of recurrence of stone-related complications. It is important to note that this was a small study in which approximately 90 percent of participants were White, so it is not yet clear whether the results will apply broadly across the population. However, if these findings are replicated in larger, more diverse studies, they could lead to new recommendations that may help reduce the risk of kidney stone recurrence.