Brady Urological Institute experts are committed to discovering the cause of disease.

Kidney stones most frequently occur in people between the ages of 20 and 60; men have kidney stones three times more often than women.
The four major types of kidney stones are defined by their make-up. The most common type is a calcium stone (75%).
Stones that are larger, irregularly shaped, higher in the kidney, or causing a blockage may need to be broken up or taken out.
Approximately 20% to 30% of people with kidney stones require some treatment.

TThe past 15 years have seen great strides in the treatment of nephrolithiasis, or renal stone disease. However, there is still much to discover about how these stones develop, and how to prevent the formation of the hardened mineral deposits that separate from urine and build up on the inner surfaces of the kidney over time.

In the 1930s, Dr. Hugh Hampton Young, the first director of the Johns Hopkins Brady Urological Institute, mentored Dr. Alexander Randall, who had a great interest in the way that kidney stones formed. Dr. Randall went on to describe little plaques-pre-calculus lesions of the renal papilla now called Randall's plaques-in the kidney, noting that stones generally formed here. Substantiated by others during the next decade, his work was nevertheless largely ignored until recently. Research into stone disease is coming full circle, thanks to the investigating work of Brian Matlaga, M.D., the new director of an active and comprehensive kidney stone program at Johns Hopkins emphasizing prevention of stone recurrence and preservation of renal function.

A full range of minimally invasive therapies are available to remove stones, including an extracorporeal shock wave lithotripter that is used to fragment and break up stones. Percutaneous, laser, and endourologic technology also allows for stone removal without the need for an incision, or, in selected cases, only through a small "keyhole" incision.

Dr. Matlaga is actively engaged in clinical and basic science research involving the formation and prevention of stone disease, and his research picks up where

Dr. Randall's left off. Important questions to be answered include:

  • Who is developing stones?
  • Why are other disease processes-hypertension, other kidney diseases, and possibly diabetes-often associated with stone formation?
  • How well are we treating patients?
  • What are the long-term consequences for kidney and pancreas function following shock wave and percutaneous therapy?

By building on Dr. Randall's work and abnormalities in the kidney on a cellular level, Dr. Matlaga hopes to develop therapies to prevent or modulate stone disease.