WHAT IS A KIDNEY STONE?
A kidney stone is a hard, crystalline mineral material formed within the kidney. Often, stones form when the urine becomes concentrated, allowing minerals to crystallize and stick together. Over time, more and more crystals bind together and the stone can grow.
A small kidney stone may pass without causing symptoms, but if stones grow large enough they can cause blockage of the ureter. This leads to varying degrees of pain, most commonly beginning in the flank or lower back and often radiating to the groin. This pain is often known as renal colic and typically comes in waves lasting 20 to 60 minutes. Other associated symptoms of passing a stone include: nausea, vomiting, fever, blood in the urine, the persistent need to urinate and painful urination. Blockage of the ureter can cause dilation of the kidney and prolonged obstruction can lead to kidney failure.
Passing kidney stones can be extremely painful, but the stones usually cause no permanent damage. Depending on your situation, you may need nothing more than to take pain medication and drink lots of water to pass a kidney stone. If a stone becomes obstructed or is too large to pass then surgery may be needed.
Pain caused by a kidney stone may change — for instance, shifting to a different location or increasing in intensity — as the stone moves down through your urinary tract.
WHAT CAUSES A KIDNEY STONE TO FORM?
Kidney stones are made when a substance normally dissolved in the urine precipitates out forming a crystal that then grows into a stone. These crystals can begin to form for many reasons:
The most common reason for stones to form is dehydration caused by drinking too little fluid. The reason this leads to stone formation is because it results in too much of the stone forming substance and not enough water to keep it dissolved in the urine. Once a crystal forms, more layers of crystal continue to pile up making a stone. 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.
Common sense has long held that the consumption of too much calcium can aggravate the development of kidney stones, since the most common type of stone is calcium oxalate. However, low-calcium diets are associated with higher overall stone risk for the typical stone former. This is thought to be due to the binding of ingested intestinal oxalate with calcium in the gastrointestinal tract. Such oxalate binding would prevent oxalate absorption resulting in lower urinary oxalate levels. In the urine, oxalate is a very strong promotor of crystal and stone formation, about 15 times stronger than calcium.
WHAT DO KIDNEY STONES LOOK LIKE?
Kidney stones do not all look the same. The color depends on what substances make up the stone. Most are yellow or brown, but they can be tan, gold, or black. Stones can be round or jagged. They vary in size from specks to pebbles, to stones as big as golf balls.
HOW ARE KIDNEY STONES FOUND?
Although some kidney stones are silent and are diagnosed as a result of an x-ray taken in the course of a general health examination, most kidney stone patients see a urologist because of the sudden pain or blood in urine that signals the stones presence. If your doctor thinks you have a stone, its location, size, and type need to be determined for proper treatment to occur.
THE FOUR MAJOR TYPES OF KIDNEY STONES:
There are different types of kidney stones. Some are made of only one substance and some are made up of a mixture of substances.
RISK FACTORS FOR STONE FORMATION:
Factors that increase your risk of developing kidney stones include:
DIAGNOSING A KIDNEY STONE:
If your doctor suspects you have a kidney stone, you may have diagnostic tests and procedures, such as:
TREATMENT OF KIDNEY STONES:
Treatment for kidney stones varies, depending on the type of stone and the cause.
Small stones with minimal symptoms:
Most kidney stones won't require invasive treatment. You may be able to pass a small stone by:
Large stones and those that cause symptoms:
Kidney stones that can't be treated with conservative measures — either because they're too large to pass on their own or because they cause bleeding, kidney damage or ongoing urinary tract infections — may require more extensive treatment. Procedures may include:
Once the acute stone event has been managed, the emphasis shifts to prevention of future attacks.
Kidney stones reoccur in about 50% of cases. Prevention of renal stone disease depends on the type of stone produced, underlying urinary chemical risk factors, and the patient's willingness to undergo a long-term prevention plan. Below we have listed some suggestions to prevent future kidney stones.