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What are kidney stones?
What salts are in kidney stones?
Kidney stone symptoms
Who gets kidney stones?
Prevent or dissolve kidney stones?
What are Kidney Stones?
How do kidney stones form? - from the blood flowing through them, the kidneys
produce urine by removing some fluid and
certain salts dissolved in that fluid. When concentration levels of
dissolved salts reach the point at which the salts no longer dissolve, they
precipitate out of solution and become solid again, forming a solid mass of tiny
crystals in the kidney’s tubal system (nephrons), called a kidney stone.
Kidney stone characteristics – size ranges from that of a grain of sand to a
golf ball. Depending on their composition, they may be smooth, round, jagged,
spiky or asymmetrical.
Kidney stones can block urine flow to the bladder causing severe pain -
or more kidney stones can block urine flow through the ureter carrying urine
from the kidney to the bladder. Small stones may not be felt, but larger stones
moving through the ureter may cause severe pain. A blockage can build up
pressure in the kidney causing swelling (hydronephrosis), which over time can
damage the kidney. A blockage further down the ureter can cause the muscular
ureter to swell (hydroureter) initiating painful spasms,
What salts are in kidney
The most common types of kidney stones are:
(~80% of all kidney
High blood calcium levels can result from such
Renal tubular acidosis - If the kidneys do not effectively eliminate acid, it builds up in the
blood. The kidney may be defective or simply overworked by an overly
Some cancers –
E.g. Multiple myeloma (cancer of bone
marrow plasma cells),
Possible dietary causes of
calcium PHOSPHATE stones –
levels of phosphate fertilizers used in growing vegetables;
Possible dietary causes of
calcium OXALATE stones - include beer, black pepper, berries, broccoli,
chocolate, spinach and tea.
(10% of kidney stones)
Occur mostly in
those having chronic infection in the urinary tract
specifically caused by bacteria that produce urease, that makes urine more
alkaline, allowing struvite to precipitate out of urine and form stones.
Uric acid stones
Occur with increased blood levels of uric acid –
Digestion produces uric acid and if the acid level in the urine is high, the
uric acid may not stay dissolved and solid uric acid particles precipitate out
in the urine, which can cling together to form a kidney stone.
About 50% of those with uric acid stones have uric acid
deposits in other body parts, called gout -
Causes of uric acid
causes – today, excess uric acid in the body is
most likely due to excess consumption of fructose in sugars, such as in sodas,
candies and sweetened foods. Also, uric acid levels are increased by consumption
of alcohol (particularly beer and wine) and purine-rich foods, including offal,
red meat and shellfish.
Medical or disease causes -
include chemotherapy, certain bone marrow disorders over-producing blood cells,
and Lesch-Nyhan syndrome (an inherited disorder).
(~2% of kidney stones)
People with cystine stones process dietary amino acids
cystine is an amino acid
Kidney Stone Symptoms
Crampy, spasmodic bouts of severe pain as stones
pass into ureter – pain usually begins in the area between
the lower ribs and the hip bone. As the stone nears the bladder, the pain often
radiates along the inner thigh. Women may feel the pain in the vulva, while men
often feel pain in the testicles.
Nausea/vomiting and frequent/painful urination
are common -
can feel like you are peeing a combination
of sharp broken glass and boiling acid!
Fever and chills -
resulting from obstruction of the ureter, which allows bacteria to become
trapped in the kidney and cause a kidney infection (pyelonephritis).
Who gets Kidney Stones?
~600,000 persons in the U.S. develop kidney
stones each year
Men are ~4-5 times more likely to develop them
than women - ~10% of men and 5% of women age 30-50 in U.S.
suffer from kidney stones, with first episode at age 20-30.
Up to 2/3
of men who have passed one stone will experience a recurrence – averaging 9
years between episodes
Kidney stones are 4-5 times more common in whites
than in African Americans
How to prevent or
dissolve kidney stones?
Treatment / Prevention