These days the problem of Kidney stones is occurring very frequently. May be our dietary habits and life style is one of the reasons behind this.
A kidney stone is a hard mineral and crystalline material formed within the kidney or urinary tract out of substances in the urine. It is expected that one in every 20 people develops a kidney stone at some point in their life.
Kidney stones are formed when the salts or minerals in the urine start crystallizing and form the nidus of a kidney stone. These stones are very tiny when they form, smaller than a grain of sand, but gradually they can grow to a quarter inch or larger.
Depending upon their composition there are four types of stones:
1) Calcium stones- most common type. The calcium that is not used by muscles and bones goes to the kidneys and is flushed out of the body. But in some instances this calcium may bind up with other waste products of the urine like oxalates to form stones.
2) Uric acid stones- occur when there is too much uric acid content in the urine that occurs due to consumption of too much of meat. So its patient needs to cut down the meat intake.
3) Struvite stones (infection stones) - composed of magnesium and ammonia. Called as infection stones as these stones are formed when the level of ammonia increases in the body and it usually occurs in urinary tract infections.
4) Cystine stones- very rare form. Cystine is a protein that is used as building block in muscles, nerves and other parts of the body. Its level is generally increased in hereditary disorder Cystinuria.
Causes: the exact reason of kidney stones formation is not known. Some of the proposed possible reasons are:
1) Lack of fluid intake: in persons who have less daily consumption of water the urine is concentrated so increasing the possibilities of kidney stones.
2) Family or personal history: if any one in your family is having stones you are prone to have this problem. Moreover if you have a prior history of stones you can develop stones in future.
3) Diet: consumption of a high-protein/ high-sodium/ low-calcium diet may lead to stone formation.
4) Limited activity: in a bed ridden person there are chances of formation of kidney stones as the bones release more of calcium.
5) Obesity: in obese person there are more chances of kidney stones.
6) High blood pressure: high blood pressure doubles the risk of kidney stones formation.
7) Gastric bypass surgery, inflammatory bowel disease or chronic diarrhea: Changes in the digestive process affect the absorption of calcium and thus increase the levels of stone-forming substances in urine.
8) Geographical location: There are regional "stone belts" having an increased risk. This is likely because of the hot climate, since these people can get dehydrated, and their urine becomes more concentrated thus leading to kidney stones.
9) Taking certain medicines such as diuretics (water tablets), antacids and thyroid medications: these medications increases the calcium content with in the body thus leading to stone formation.
10) As a side effect of certain other health problems like in gout (where there is increase in uric acid content so can lead to uric acid stones), hypercalcinuria (increase in calcium content so calcium stones can occur), hyperparathyroidism (increase in calcium level), cystinuria(increase in cystine content so cystine stones can occur), hyperoxaluria (increase in oxalate content which then binds up with calcium to form calcium oxalate stones) etc.
Symptoms: the various symptoms of kidney stones include:
1) Severe pain or aching in the back on one or both sides.
2) Sudden onset of excruciating, cramping pain in their low back and/or side, groin, or abdomen. Changes in body position do not relieve this pain. The pain typically waxes and wanes in severity, characteristic of colicky pain (the pain is sometimes referred to as renal colic). It may be so severe that it is often accompanied by nausea and vomiting
3) Bloody, cloudy or smelly urine.
4) A frequent urge to urinate, or a burning sensation during urination.
5) Fever and chills that occurs due to associated kidney infections.
Diagnosis: along with taking in to consideration the various symptoms associated with the problem, the following tests can help in diagnosing the condition.
1) Urine Analysis: to look for signs of infection and to check for the levels of protein, magnesium, calcium etc. in the urine.
a) Microscopic study of urine, which may show proteins, red blood cells, pus cells, bacteria, cellular casts and crystals.
b) Examination of the culture of urine sample to detect urine infection.
c) 24 hour urine collection to measure total daily urinary volume, magnesium, sodium, uric acid, calcium, citrate, oxalate and phosphate etc.
2) Blood tests: Full blood count for the presence of a raised white cell count (Neutrophilia) suggestive of infection, a check of renal function and to look for abnormally high blood calcium blood levels (hypercalcaemia).
3) X-ray of the abdomen - stones that contain calcium usually show up white on X-ray images.
4) Intravenous urogram (IVU) - this involves an injection of a special dye that shows up the whole urinary system on X-ray images, revealing stones that can't usually be seen.
5) Ultrasound scan - this uses high frequency sound waves to produce an image of the internal organs and thus can give an overview of shape, size and location of the stone.
6) Non- contrast helical computerized tomography - this produces pictures from a series of X-ray images taken at different angles - it is sometimes used to diagnose kidney stones, and is thought to be the most accurate diagnostic test.
Treatment:
1) Dietary precautions: first try to rule out the type of kidney stones with the help of various lab tests. When you got to know about the type of kidney stone (calcium stone/ struvite stone/ cystine stone/ uric acid stone) then limit that food ingredient which is causing the stones. It is discussed in details as follows:
a) In case of calcium oxalate stones- if oxalate level is high then limit the supply of oxalates. High oxalate foods are: spinach, beets, okra, chocolates, tea, sweet potatoes, etc. take calcium rich diet it will bind up with the excess of oxalates and will reduce their level in blood and so in urine.
But if urinary calcium level is high then calcium rich diet may increase the incidence of stone formation. Other food ingredients that increase the level of urinary calcium should also be limited like sugars; proteins and sodium are believed to increase the urinary calcium levels. Fiber rich foods decrease the absorption of calcium from blood so decreases the levels of urinary calcium so they are recommended in kidney stones. Potassium also reduces the urinary calcium excretion so potassium rich foods like bananas, citrus fruits (except grapefruit), potatoes etc. are also recommended in this case.
b) In case of Cystine stones- limit the protein intake. Protein rich foods are fish, meat, poultry, dairy products etc.
c) In uric acid stones- patients need to limit the animal protein intake like meat.
d) In struvite stones- as these stones are associated with kidney infection so first line of prevention is keep the urine free of bacteria. Certain antibiotics recommended by some physician can be used in this case.
2) Fluid intake: the best and the safest way to prevent kidney stones, is to use as much of liquids (mainly plain water) as you can so that the urine is no longer concentrated. This will prevent the crystallization of the various urinary wastes.
3) Avoid use of soft drinks as these contain substances that can affect calcium metabolism and thus may lead to stone formation.
4) Certain medications can be used to reduce the level of urinary calcium, uric acid, proteins etc or to reduce the associated pain but these drugs should be used only after consulting the doctors.
Most stones pass out of the body by themselves without any external intervention but if the stones are not removed with in 4- 8 weeks then other methods should be tried out like use of shock waves as in lithotripsy or by surgical removal because if the stones will remain for long they may develop infections.
Complications
If a stone stays inside one of your kidneys, it usually doesn't cause a problem unless it becomes so large it blocks the flow of urine. This can cause pressure and pain, along with the risk of kidney damage, bleeding and infection. Smaller stones may partially block the thin tubes that connect each kidney to your bladder or the outlet from the bladder itself. These stones may cause ongoing urinary tract infections or kidney damage if left untreated.
Since most patients have two kidneys, a temporary obstruction of one is not of great significance. For those patients with only one kidney, an obstructing stone can be a true emergency, and the need to relieve the obstruction becomes greater. A kidney that remains completely obstructed for a prolonged period of time may stop working.
Infection associated with an obstructing stone is another emergent situation. When urine is infected and cannot drain, it acts like an abscess and can spread the infection throughout the body (sepsis). Fever is a major sign of this complication, but urinalysis may show an infection and cause the urologist to act to place a stent or remove the stone.
Follow up
Even if the stones are removed one needs to be careful in future as there are chances of recurrences. So the safest way is to consume as much of water as you can thus decreasing the risk of kidney stones.
