A kidney stone is a hard mass developed from crystals that separate from the urine
and build up on the inner surfaces of the kidney. Normally, urine contains chemicals
that prevent or inhibit the crystals from forming. These inhibitors do not seem
to work for everyone, however, so some people form stones. If the crystals remain
tiny enough, they will travel through the
tract and pass out of the body in the urine without being noticed.
may contain various combinations of chemicals. The most common type
of stone contains calcium in combination with either oxalate or phosphate. These
chemicals are part of a person's normal diet and make up important parts of the
body, such as bones and muscles.
A less common type of stone is caused by infection in the
This type of stone is called a struvite or infection stone. A bit less common is the uric
acid stone. Cystine stones are rare.
Most kidney stones eventually pass through the
on their own within 48 hours, with ample fluid intake. Pain medications can
be prescribed for symptom relief. There are several factors which influence the
ability to pass a stone. These include the size of the person, prior stone passage,
prostate enlargement, pregnancy, and the size of the stone. A 4 mm stone has an
80% chance of passage while a 5 mm stone has a 20% chance. The doctor usually asks
you to save the passed stone(s) for testing. (You can catch it in a cup or tea strainer
used only for this purpose.)
Certain drugs or lifestyle changes can be used to help dissolve
stones. See preventive therapy for more information.
Surgical Therapy: Surgery
may be needed to remove a kidney stone for the following reasons: if it does not pass after a reasonable period of time and causes
constant pain; if it is too large to pass on its own or is caught in a difficult
place; if it blocks the flow of urine, causes ongoing urinary tract infection, damages
kidney tissue or causes constant bleeding. Various surgical options are now available
to patients with kidney stones. Our practice offers all of the latest innovations
in stone treatment.