Doctors do not always know
what causes a stone to form. While certain foods may promote stone formation
in people who are susceptible, scientists do not believe that eating any
specific food causes stones to form in people who are not susceptible.
A person with a family
history of kidney stones may be more likely to develop stones. Urinary tract
infections, kidney disorders such as cystic kidney diseases, and metabolic
disorders such as hyperparathyroidism are also linked to stone formation.
In addition, more than 70
percent of patients with adequate hereditary disease called renal tubular
acidosis develop kidney stones.
hyuperoxaluria are two other rare inherited metabolic disorders that often
cause kidney stones. In cystinuria, the kidneys produce too much of the
amino acid cystine. Cystine does not dissolve in urine and can build up to
form stones. With hyperoxaluria, the body produces too much of the salt
oxalate. When there is more oxalate than can be dissolved in the urine, the
crystals settle out and form stones.
occurs when the body absorbs too much calcium from food and empties the
extra calcium into the urine. This high level of calcium in the urine causes
crystals of calcium oxalate or calcium phosphate to form in the kidneys or
Other causes of kidney
stones are hyperuricosuria (a disorder of uric acid metabolism), gout,
excess intake of vitamin D, and blockage of the urinary tact. Certain
diuretics (water pills) or calcium-based antacids may increase the risk of
forming kidney stones by increasing the amount of calcium in the urine.
Calcium oxalate stones may
also form in people who have a chronic inflammation of the bowel or who have
had an intestinal bypass operation, or ostomy surgery. As mentioned above,
struvite stones can form in people who have had a urinary tract infection.
What Are the Symptoms?
Usually, the first symptom
of a kidney stone is extreme pain. The pain often begins suddenly when a
stone moves in the urinary tract, causing irritation or blockage. Typically,
a person feels a sharp, cramping pain in the back and side in the area of
the kidney or in the lower abdomen. Sometimes nausea and vomiting occur with
this pain. Later, the pain may spread to the groin.
If the stone is too large
to pass easily, the pain continues as the muscles in the wall of the tiny
ureter try to squeeze the stone along into the bladder. As a stone grows or
moves, blood may be found in the urine. As the stone moves down the ureter
closer to the bladder, a person may feel the need to urinate more often or
feel a burning sensation during urination.
If fever and chills
accompany any of these symptoms, an infection may be present. In this case,
a doctor should be contacted immediately.