Update on Urinary Stone Formation

Submitted by UCSF Urology on December 19, 2016 at 9:59 am

As a teaching institution, UCSF Urology patients are seen by Dr Stoller with stone imageworld-class physicians, many of whom are also internationally recognized researchers.  The added benefit of being seen by Clinician Researchers as their doctor is that these physicians are often at the forefront of their field.  Such is the case for Marshall Stoller, MD, and Tom Chi, MD, who use basic science as well as epidemiologic approaches to continuously improve the care of patients with urinary stone disease.  

Dr. Stoller presented an overview of the latest research at the American Urological Association 2016 national conference focusing on the events leading up to a stone disease precursor called “Randall plaques.”  As reported by the conference, his review, combining “perspectives from urology, chemistry, flow dynamics and other disciplines has created a better picture of the events that precipitate stone formation.”  

At the conference, he explained how flow dynamics that underlie the creation of Randall plaques appear to be key to stone formation.  Small calcifications within the kidney, Randall plaques have long been thought to be precursors to kidney stone disease, but just how they lead to stone formation has been unclear. According to the new theory based on high-resolution imaging, mineral accretions initially form in tubules at the base of the renal papilla, leading to the formation of interstitial biominerals (Randall plaques) at the tip of the papilla.  Biomineral accumulation occurs in part because urine tubules and blood vessels must adapt to the shape of the papilla, which narrows at the tip. The biominerals ultimately change flow dynamics, and that can lead to further precipitates. Depending on each individual’s anatomy, concentric rings of mineral deposits can build up, slowly narrowing the openings of the tubules within the papilla. If these stone elements become dislodged, they can obstruct the ureter, causing severe pain.  

 “The closer we are to understanding the exact science of how stones are formed,” says Dr. Stoller, “the closer we will come to designing precision treatments to improve this painful condition.”

A critical key to understanding stone formation is the epidemiologic information that can only be garnered and understood through the creation of a robust, carefully collected database.  Dr. Chi has designed and has started to populate such a tool at UCSF utilizing an automated approach.

“Our goal is to track how patients experience kidney stone disease and what their treatment outcomes are like in a real time manner. One innovation we are using for these studies is a means to automate patient data collection directly from their electronic medical record,” explains Dr. Chi. “This can only be done with the generous support of volunteer patients who agree to contribute their clinical information, fill out surveys and donate samples for current and future studies.  We are grateful for their participation and hope creating this new body of knowledge will contribute to the cures of tomorrow.”