It can cause excruciating pain, but doctors
say the best medicine for a kidney stone usually is to
let it pass on its own.
Millions a year develop kidney stones.
In January, Boston Legal star William Shatner found
some good in his painful kidney-stone episode: He sold
the stone to a quirky online site for $25,000 to raise
money for Habitat for Humanity.
A kidney stone forms out of chemicals
in the urine. A stone as small as a grain of sand or as
large as a pearl may stay in the kidney or break loose
and travel down the urinary tract.
It may pass all the way out of the
body without causing discomfort, but if it gets lodged
in the wrong spot or grows too big and blocks the flow
of urine, it can cause severe pain in the back or side.
About 90% of kidney stones, typically
diagnosed through a CT scan or X-ray, pass on their own
in a few days or a few weeks.
"Our first choice is to do nothing,"
says Peter Schulam, a urologist and director of the UCLA
Stone Treatment Center in Los Angeles. "The only reason
to intervene is if there is a sign of an infection such
as fever or the pain can't be controlled."
Doctors prefer a conservative approach
to treating stones because of the risk of infections and
damage to the kidney that some intervention techniques
can cause, Schulam says.
The most common non-invasive method
to treat stones is a process called lithotripsy, in which
a machine sends non-electrical shock waves directly to
the kidney stone. The shock waves break a large stone
into small stones that are easier to pass in the urine.
Minimally invasive surgical techniques
also have been developed to remove kidney stones. This
may be done through a small incision in the skin or through
a very thin scope (ureteroscopy) that is passed through
the urethra and bladder into where the stone is located.
Though medical research has done
little to eliminate the inevitable pain of stones, progress
has been made in understanding ways to reduce the risk
of forming new stones.
"In terms of prevention, we have
come a long way," says Eric Taylor, a researcher and kidney
specialist at Brigham and Women's Hospital in Boston.
"If people are really motivated at making dietary and
lifestyle changes and taking some medications, one can
dramatically reduce the recurrence of stones."
