KIDNEY DISEASE:
KIDNEY STONES
Mitchell Thom
Ms. Bragg
05/03/11
SBI4U
WHAT IS IT?(BACKGROUND INFO)

In science class, we learn about different types of
chemical reactions; one being a reaction involving
a precipitate. Kidney stones, known for causing
excruciating amounts of pain, are hard,
crystalline stones made because of precipitates
formed in the kidneys. The precipitates are due
to certain combinations of solutes in the nephron
depending on the type of stone. These stones
eventually pass through the ureter, blocking
urine and causing the ureters to swell, which is
the source of the great pain that patients
experience. Another name for this condition is
nephrolithiasis.
WHAT IS IT? (TYPES OF STONES)

There are different types of kidney stones, the
most common being calcium oxalate and calcium
phosphate stones, while there are also cysteine
stones, uric acid stones, and other uncommon
types like struvite stones. The stones are
organized into two types: alkaline and acidic. The
calcium phosphate and oxalate stones are
categorized into the alkaline category, while the
cysteine, uric acid, and struvite stones are named
acidic.
TYPES OF STONES CNTD.
Cysteine and struvite stones are different from
the other types of stones.
 Cysteine stones are developed due due to excess
cysteine in the urine because of a genetic disorder
called cystinuria. In this condition, trouble with
the transport of amino acids leads to a higher
concentration of amino acids in the urine. Since
cysteine is the least soluble of all amino acids, it
tends to precipitate in urine in the form of stones.
 An infection in the urinary tract can lead to
kidney stones, and these are known as struvite
stones.

HOW DOES IT AFFECT THE KIDNEY?

Kidney stones do not affect any specific area of
the nephron. Rather, the kidney stones are
formed in small fragments wherever there is a
decrease in urine volume and/or an excess of
precipitate-forming solutes in the urine. This
means that miniscule kidney stones can form
anywhere between the bowman’s capsule and the
collecting duct, and the collecting ducts will
gather in the renal pelvis where all of the
fragments can form a larger kidney stone. From
here, the kidney stone will enter the ureter,
which is only 0.4 mm in diameter.
LET’S GET SCIENTIFIC

Strenuous exercise without fluid intake, low
volumes of urine, and a high concentration of
precipitate-causing solutes are all conditions
where kidney stones can form, but why?
Strenuous exercise means
more water reabsorption,
since there is will be a higher
concentration of NaCl in the
blood due to less water. This
means water will diffuse into
the blood because it will
follow NaCl. This leaves a
lower volume of urine, and
therefore a higher
concentration of solutes.
SCIENCE OF KIDNEY STONES

With these factors in mind, picture fluids moving
through the nephron.
If there is more water, there is
higher pressure in the
nephron. This means the fluids
will move more quickly and
have a lower chance of settling.
If there is a low volume, the urine will sit in the
nephron for longer, and this allows precipitateforming solutes to mix, which will result in a
greater chance of kidney stone fragments
forming.
SYMPTOMS OF KIDNEY STONES

Include:
Excruciating onsets of pain in your sides or lower
back
 Blood in Urine
 Difficulty Urinating
 Fever and Chills (If associated with infection in
urinary tract)
The ureter is only 0.4 mm in diameter, so even very
small kidney stones can cause large amounts of pain.
Because of the crystalline shape of the kidney stone, its
uneven, jagged edges can cut into the sides of the
renal pelvis and the ureter, causing pain and blood in
the urine. If the stone is large enough, it can block
the transport of urine to the bladder, causing the
difficulty to urinate.

DIAGNOSIS OF KIDNEY STONES
Diagnosis is suspected by the symptoms of
kidney stones, but confirmed by a helical CT scan
of the abdomen.
 A helical CT scan is a specialized form of CAT
scan that allows patients to be continuously be
scanned with movement. It also permits a higher
definition of internal structures, like the kidneys
and ureter. This is the procedure used because
patients are usually in so much pain they are
treated as emergency cases and need to be
diagnosed quickly even if they are writhing in
pain. The helical CT scan can provide 3D images.

DIAGNOSIS CTND.

In the cases of blood sampling and urinalysis,
neither would be efficient at determining the
presence of kidney stones because:
The patient may not be able to urinate
 The patient will most likely not cooperate due to pain
 The patient will need to be diagnosed in as little time
as possible, and these procedures will take a very
long time to centrifuge the urine, etc.

ARE KIDNEY STONES INHERITED?


No. Kidney stones can develop in anybody. However,
there are certain diseases, like cystinuria, which
was mentioned before, that can cause excess cysteine
to be in a person’s urine. This doesn’t mean that
cysteine kidney stones can be inherited, but there are
genetic disorders involving concentrations of solutes
in urine that can increase your chances of having
kidney stones.
Eg. Gout (increased concentration of urea in blood
and urine), Hypercalciuria (high calcium in urine,
half of patients get kidney stones in their lives), and
hyperoxaluria (high chances of calcium oxalate
stones). All of these diseases are genetic disorders.
KIDNEY STONES INHERITED? CTND.

For those who do not have any of these disorders,
kidney stones are still possible. Any of these
reasons could cause kidney stones:
Dehydration, more reabsorption.
 Eating high-oxalate foods leaves more precipitateforming oxalate solute in urine.
 Taking in excess calcium leaves more precipitateforming calcium solute in urine.
 Eating very protein-heavy diets can lead to excess
uric acid in the diet due to digestion, which can lead
to uric acid stones.

HISTORY OF TREATMENT

Kidney stones have existed since the beginning of
civilization.
In 1901, an Egyptian mummy dating back to 4800 BC
was found with a kidney stone in its pelvis.
 Individuals like Sir Isaac Newton and Benjamin
Franklin also had kidney stones.
Practices of Lithotomy, or surgical removal of kidney
stones, have been used for centuries. (It is one of the
oldest surgical procedures created.)
In 1878, Henry Jacob Bigelow invented the practice of
litholapaxy, which dropped mortality rates from 24%
to 2.4%.
li·thol·a·pax·y: The procedure of crushing of a stone in
the bladder and washing out the fragments through a
catheter.

TREATMENT CNTD.


It wasn’t until 1980 that the current treatment for
kidney stones was created. Dormier MedTech, an
aircraft manufacturer, introduced extracorporeal
shock wave lithotripsy at this point in time, a
procedure that breaks up stones through acoustic
pulses.
ESWL: a non-invasive procedure where an x-ray
locates the kidney stone, and a sedated patient has a
high-intensity acoustic pulse aimed at the area with
increasing intensities to get the patient used to the
sensation. The final power level depends on the
patients threshold, by this point the stone should
break. If it hasn’t yet, the patient is sedated more
heavily to allow a higher power level.
ESWL

ESWL isn’t without risks, unfortunately. The
shockwaves can lead to capillary
damage, hemorrhage, renal failure,
and hypertension.
Fragments of a
Kidney Stone after
ESWL treatment
WERE YOU PAYING ATTENTION?
1. Which types of kidney stones are acidic and
alkaline?
 2. Why can strenuous exercise without fluid
intake increase the chances of a kidney stone
forming?
 3. How can you decrease your chances of getting
a kidney stone?

ANSWERS

1.

2.
3.
BIBLIOGRAPHY
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Photos:
X-Ray: Myqute. "How to Say Goodbye to Kidney Stones."
Promote Your Blog, Get Discovered and Expand Your
Audience with BloggersBase.com. Sept. 2009. Web. 03 May
2011. <http://www.bloggersbase.com/sports-andfitness/how-to-say-goodbye-to-kidney-stones/>.
0.8 cm Kidney Stone: Barton, Joe. "What about What Do
Kidney Stones Look like on Ultrasound." Kidney Stone
Treatment - Pain Relief With This Safe And Effective Home
Kidney Stone Remedy! Web. 03 May 2011.
<http://www.fastkidneystonetreatment.com/what-aboutwhat-do-kidney-stones-look-like-on-ultrasound>.
"Renal System." The Birmingham City University Health
Website. Web. 03 May 2011.
<http://www.hcc.uce.ac.uk/physiology/renalsystem.htm>.
"CT Scan." Shikoku.ne. Web. May 3.
<http://user.shikoku.ne.jp/tobrains/exam/CT/CT-e.html>.
BIBLIOGRAPHY CNTD.
Websites:
 (Amazing Source) Shier Jr., William. "Kidney
Stones Symptoms, Treatment Options, Diet,
Causes, Signs and Prevention by
MedicineNet.com." Medicine Net. Web. 03 May
2011.
<http://www.medicinenet.com/kidney_stone/articl
e.htm>.
 "Department of Urology, University of Kansas
Medical Center." Kidney Stones. 2011. Web. 04
May 2011.
<http://www2.kumc.edu/urology/kidney_stones.as
p>.
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