Page 1 - Kidney Stones
P. 1
Urological Health
Kidney stones
Stones may form in the kidneys, occasionally blocking the drainage of urine and causing pain.
he kidneys play an important role in eliminating Low urine output may be due to inadequate fluid
Twaste products from the body. These waste intake or excessive fluid losses, such as with frequent
products normally remain dissolved in the urine as it heavy perspiration or chronic diarrhea. Alternatively,
passes through the kidney drainage system (calyces, the urine may be overloaded with a substance
renal pelvis and ureter). Kidney stones are crystalline because of excessive dietary intake, excessive
particles that form in the urine, often producing pain production by the body, or changes in the function of
when they obstruct urine drainage from a kidney. the bowels or kidneys. Kidney stones are rarely a sign
of kidney disease and stone formation is uncommon in
people with poorly functioning kidneys.
Most often kidney stones take many months or
years to grow to a size that can produce symptoms,
kidneys generally, by obstructing urine drainage from a
kidney. Occasionally, stones may form more rapidly.
stone Because stones usually do not cause symptoms
in calyx soon after they are formed, it is impossible to know
how rapidly a person’s stone or stones have formed.
Approximately 50% of stone formers will develop a
stone second kidney stone within 10 years of their first stone,
obstructing and 75% within 20 years.
ureter
ureters Stone types
Most kidney stones contain calcium, usually calcium
bladder oxalate or calcium phosphate. About 10% of kidney
stones are composed of uric acid, a by-product of
urethra breakdown of meat, poultry and fish products, which
is excreted in higher concentration in people with
gout. Struvite stones occur in association with certain
Approximately one in ten Canadians will develop a bacterial infections of the urine.
kidney stone. This problem is more common in men
than in women, and it occurs rarely in children. Kidney Investigation of kidney stones
stone formation in most adults is not thought to be an
inherited condition even if several family members Most kidney stones can be seen on a simple x-ray.
have had stones. Children with kidney stones, Uric acid stones, however, are not visible on simple
however, are more likely to have an inherited risk. x-rays and require other investigations. An ultrasound
Some children have severe forms of stone disease that or a CT scan is often very useful in identifying the
require thorough investigation and frequent follow-up. size and location of all types of kidney stones. An
IVP (intravenous pyelogram) is occasionally ordered
Kidney stone formation and involves an intravenous injection of “dye” that is
excreted in the urine, demonstrating the presence of
Kidney stones form when the concentration of certain a stone and the function of the kidneys.
substances in the urine exceeds the amount that stays Urine and blood tests will help in monitoring kidney
dissolved. This can happen when the urine becomes function and determining the cause of kidney stone
over-concentrated due to low urine volume or
excessive excretion of a substance. formation. The frequency of tests recommended
depends on the severity of the stone disease, the
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