Illustration of a large kidney stone trapped inside the kidney.

Large Kidney Stones: Between a Rock and a Hard Place

By Stephen Overholser, MD

Kidney stones come in all shapes and sizes. For this article, I’d like to focus on the bigger ones. I will use 2 centimeters as our cutoff, but even some 1.5 centimeters stones could be considered large, especially if they are dense or trapped inside a pocket in the kidney.

All stones can cause issues, but large stones are particularly problematic. They can be a source of recurrent urinary tract infection, blood in the urine, and flank pain. If left untreated, they enlarge to a point where they impact how the kidney functions and can permanently damage it. They are often too big for patients to pass safely and can be resistant to some of our techniques of treating them efficiently. Shockwave lithotripsy (ESWL) is an excellent approach to stones eligible to receive it. However, this is a decision to be made between your urologist and you. If your urologic team determines ESWL alone to be insufficient upfront or after the stone resists its effects, there are still ways we can help.

The two main approaches involve going into the urinary tract and using cameras and tools to treat or retrieve the stones. One approach uses retrograde access, which involves passing through the bladder up into the ureter and kidney. The other uses percutaneous renal access. This requires making a small incision in the skin over the kidney and getting into the kidney with a tube. Both have advantages and disadvantages.

The retrograde approach, also known as ureteroscopy, requires no incisions in the skin and sometimes carries less perioperative risk, making it a great option. However, it can yield incomplete results for larger stones. Its stone-free rate -the frequency of follow-up X-rays showing removal of all visible stone- goes down as stone size goes up. This can lead to multiple return trips to the operating room, a common occurrence for patients who make stones repeatedly over time.

Percutaneous access or percutaneous nephrolithotomy is more involved than the retrograde approach, but most of that work is performed by your operative team. Once access is gained to the collecting system of the kidney, more efficient and effective devices can be used inside to quickly treat a large amount of stone with little harm done to the kidney. While the procedure may sound more painful, current surgical and anesthetic techniques can leave patients feeling the same or better than a retrograde approach would. Best of all, this approach yields the highest stone-free rate possible for this stone type.

The best treatment for kidney stones will always be prevention. Hydration, reducing salt intake, and managing the other risk factors determined by your urologist form the foundation of any stone prevention plan. However, when stones form and then grow into large stones, your stone experts at Georgia Urology can really make an impact. No matter how big or hard the stone gets, we will make every effort to get you stone-free safely. After treatment success, we will then double back and help you identify how such a large stone formed and provide you a roadmap for prevention.

When you are stuck between a rock and a hard place, request Georgia Urology, the most respected and venerated kidney stone experts in Georgia. You can either discuss this with your PCP or utilize our rapid response Stone11 hotline. Whether it is me or one of our other stone experts, we will be there to support you from start to finish.