Kidney Stones
What are kidney stones?
They are the concentration of minerals (calcium), acid salts and organic matter that are formed in the inner surfaces of the kidneys in the shape of hard, stone-like crystals which generally continue to grow in size and disrupt renal functions.
The center of this concentration can be a clump of bacteria, degenerated tissue, sloughed-off cells, or a tiny blood clot. Minerals collect around this entity and coat it, increasing the stone’s size. Most kidney stones contain calcium.
What are the symptoms?
Kidney stones often do not cause any symptoms.
The fist symptom usually is sharp cramping pain in the side and back, below the ribs (sudden, happens when the stone moves in the urinary tract and blocks the flow of urine)
Fluctuations in pain intensity, with periods of pain lasting 20 to 60 minutes
Pain waves radiating from the side and back to the lower abdomen and groin
Bloody, cloudy or foul-smelling urine
Pain on urination
Nausea and vomiting
Pain may spread to the groin
Blood in your urine (urine appears pink)
Persistent urge to urinate (due to stone moving down the ureter, closer to the bladder)
Fever and chills (signs of an infection)
Recurring urinary tract infections
What are the causes?
Doctors do not always know what causes stones as its common for kidney stones to have no definite, single cause.
Kidney stones form when the components of urine — fluid and various minerals and acids — are out of balance. There are certain circumstances that increase the likelihood of stone formation. One is the drop in fluid, e.g. not drinking enough water. The other is the rise of mineral e.g. due to metabolic conditions or infections. Normally, the substances that make up kidney stones are diluted in the urine. However, when the urine is concentrated minerals may crystallize, stick together and solidify, resulting in kidney stones.
A person with a family history of kidney stones may be more likely to develop stones i.e. urinary tract infections, kidney disorders (e.g. cystic kidney diseases) and certain metabolic disorders (e.g. hyperparathyroidism) are also linked to stone formation.
Some drugs promote specific types of kidney stones, e.g. furosemide (Lasix), used in treating heart failure and high blood pressure and topiramate (Topamax), an anti-seizure drug. People who take the protease inhibitor indinavir, a medicine used to treat HIV infection, may also be at increased risk of developing kidney stones.
Certain foods may promote stone formation in people who have a family history, but scientists do not believe that eating any specific food leads to the formation of stones in people who are not susceptible.
Most kidney stones contain crystals of more than one type. Determining the type helps identify the underlying cause, as follows:
Calcium stones: (usually in the form of calcium oxalate) may form in people who have chronic inflammation of the bowel or who have had an intestinal bypass operation, or ostomy surgery. Dietary factors, high doses of vitamin D, and metabolic disorders can also be a contributing factor. Roughly four out of five kidney stones are calcium stones. Oxalate is found in some fruits and vegetables, but the liver produces most of the body's oxalate supply.
Struvite stones: can form in people who have had a urinary tract infection. It is found more often in women.
Uric acid stones: These stones are formed of uric acid which is more likely to develop with a high-protein diet. Gout also leads to uric acid stones
ystine stones: These stones are rare as they form in people with a hereditary disorder that causes the kidneys to excrete excessive amounts of certain amino acids (cystinuria).
Treatment and prevention:
Most kidney stones can pass through the urinary system with plenty of water to help move the stone along. The patient might be asked to stay home drink lots of fluids and take pain medication when needed. The doctor usually requires saving the passed stones for testing.
There are several ways to go about treatment:
Lifestyle Changes:
Drink more liquids (water is preferable). For people with a history of kidney stones, doctors usually recommend passing at least 2.3 liters of urine a day. To do this, you'll need to drink about 3.3 liters of fluids every day — and it could be more depending on the climate.
Drink a glass of lemonade every day as it increases the levels of citrate in your urine, and citrate helps prevent stone formation. Avoid powdered lemonade mixes.
Recent studies show that foods with high calcium pay prevent for calcium stones because dietary calcium binds with oxalates preventing them from being absorbed from the intestine and excreted by the kidney to form stones. However, taking calcium pills may increase the risk of stones especially if not taken with meals.
When you absorb too much dietary calcium from the intestine, restrict calcium intake.
Doctor might tell you to avoid food with added vitamin D and certain types of antacids with a calcium base
If you have highly acidic urine you may need to eat less meat, fish, and poultry
To prevent cystine stones, a person should drink enough water each day. More than a gallon of water may be needed every 24 hours, and a third of that must be drunk during the night.
An overall diet low in salt and very low in animal protein can greatly reduce your chance of developing kidney stones.
If you are prone to forming calcium oxalate stones, the doctor may ask you to limit or avoid certain foods if their urine contains an excess of oxalate.
Foods with oxalate that you need to eat less of:
star fruit
rhubarb
refried beans
spinach
beets and beet greens
almonds
swiss chard
collards
sesame seeds
wheat germ
soy products e.g. soybean crackers
peanuts
okra
chocolate
black Indian tea
sweet potatoes
grits
grapes
celery
green pepper
red raspberries
fruit cake
strawberries
armalade
liver
Medical Therapy
The type of medication your doctor prescribes will depend on the kind of kidney stones you have:
Calcium stones: thiazide diuretic or a phosphate-containing preparation. However, if it is due to renal tubular acidosis, the doctor may suggest taking sodium bicarbonate or potassium bicarbonate. Doctors usually try to control hypercalciuria to prevent calcium stones by prescribing certain diuretics, such as hydrochlorothiazide. These medicines decrease the amount of calcium released by the kidneys into the urine by favoring calcium retention in bone. They work best when sodium intake is low.
Uric acid stones: allopurinol (Zyloprim, Aloprim) is used to reduce uric acid levels in the blood and urine. Sometimes it can dissolve the uric acid stones.
Struvite stones: long-term use of antibiotics in small doses is useful keep the urine free of bacteria that cause infection. For struvite stones that have been totally removed, the first line of prevention is to keep the urine free of bacteria that can cause infection. A patient’s urine will be tested regularly to ensure no bacteria are present. If struvite stones cannot be removed, a doctor may prescribe a medicine called acetohydroxamic acid (AHA). AHA is used with long-term antibiotic medicines to prevent the infection that leads to stone growth.
Cystine stones: they are the hardest and the most difficult stones to treat. The doctor may prescribe certain medications to alkalinize the urine or to bind the cystine in the urine in addition to recommending an extremely high urine output. If the stones cannot be controlled by drinking more fluids, a doctor may prescribe medicines such as Thiola and Cuprimine, which help reduce the amount of cystine in the urine.
Surgical Treatment
Surgery is not always the option to remove kidney stones, unless the kidney stone:
Method of treatment, potential risks and complications should be discussed with the doctor before making a treatment decision.
Extracorporeal shock wave lithotripsy (ESWL). It is the most common procedure for treating kidney stones. It uses shock waves to break the stones into tiny pieces that are then passed in your urine. To reduce the risk of complications, doctors usually tell patients to avoid taking aspirin and other medicines that affect blood clotting for several weeks before treatment. In some cases, the doctor will insert a small tube called a stent through the bladder into the ureter to help the fragments pass. Sometimes the stone is not completely shattered with one treatment, and additional treatments may be needed.
Percutaneous nephrolithotomy. This treatment is often used when the stone is quite large or in a location that does not allow effective use of ESWL the surgeon may remove the kidney stone through a tiny incision in your back, creating a tunnel directly into the kidney. Using an instrument called a nephroscope, the surgeon locates and removes the stone,
Parathyroid surgery. Some calcium stones are caused by overactive parathyroid glands, which are located on the four corners of your thyroid gland, just below your Adam's apple. When these glands produce too much parathyroid hormone, your body's level of calcium can become too high, resulting in excessive excretion of calcium in your urine. Most often, this is the result of a small benign tumor in one of your four parathyroid glands. A doctor can surgically remove the tumor.
Ureteroscopic stone removal. This procedure may be used to remove a stone lodged in a mid and lower ureter stones. No incision is made in this procedure. The stone is snared with a small fiberoptic instrument (ureteroscope) that's passed into the ureter through your bladder. The surgeon will locate the stone and will either remove it or shatter it by ultrasound or laser energy.