What are Kidney Stones?

The kidneys are a part of the body’s urinary system. They are bean-shaped organs that filter the blood of metabolic wastes, which are then excreted as urine. The process of kidney stone formation is called nephrolithiasis. The word comes from the Greek nephros, meaning kidney, and the Greek lithos, meaning stone.

Kidney stones are solid pieces of material made of dissolved minerals in urine and occur when urine becomes too concentrated. They vary in size and can be as small as a grain of sand, as large as a golf ball, and any size in between. They are usually yellow or brown and may be smooth or jagged. They originate in the kidney and usually leave the body when urine is passed. The smallest ones may pass through without you taking any notice. Those are called “silent stones”.

Many kidney stones don’t cause symptoms and are not discovered until it begins to make its way from the kidney to the bladder. Passing a kidney stone causes excruciating pain, especially when it becomes a blockage in the urethra (thin tube that takes the urine to its exit point). In many cases medical removal is necessary.

A person’s chance of passing a stone without medical intervention depends on several different factors, including the size of the person, prostate enlargement, prior passing of a stone, and the size of the stone. There is an 80% chance that a stone no larger than 4mm can be passed without assistance, and only a 20% chance of that occurring with a 5mm stone.

Different Types of Kidney Stones

There are different types of kidney stones, classed according to their mineral composition.

· Struvite stones contain the waste product ammonia and the mineral magnesium.

· Cystine stones are the hardest stones, and also the rarest form. Cystine is an amino acid (basic structural building unit of proteins) found only in people diagnosed with a condition known as “cystinuria,” which is handed down through family genetics.

· Uric acid stones are formed when the urine contains an excess of acid.

· Calcium stones are the most common form. Excess calcium usually exits the body through the urine, but if it does not, it combines with other waste products and creates a stone.

Signs and Symptoms

Kidney stones are often discovered while receiving medical attention for another condition, something like a urinary tract infection or blood in the urine. The most often reported symptom is intense pain that comes on as a sharp, cramping pain in the back and side area of the kidney. As the stone makes its way down toward the bladder, the pain may extend to the groin and other symptoms may show up, including any or all of the following:

· Nausea

· Vomiting

· Burning sensation during urination

· Blood in the urine

· Cloudy and/or smelly urine

· Constant feeling of needing to urinate

How Kidney Stones are Diagnosed

When doctor suspects there may be stones, he will probably do a blood test and a urine test. The blood test will be looking for uric acid or excess calcium, and the urine test will check to see if you are excreting too many of the minerals that cause the stones. The diagnosis may be confirmed with one or more of the following imaging tests:

• X-ray: In this test, pictures are taken with photons of X-ray light. The use of X-radiation can go through human skin tissue but is stopped by dense bones.
• Intravenous pyelogrophy: Stones that don’t show up on a regular X-ray will show up here. A dye is injected into a vein and moves through the areas where a stone may be present. They dye highlights those areas and a series of X-rays are taken.
• Spiral CT scan: This test also finds stones that don’t show up on a regular X-ray. No dye is needed, and the entire abdomen can be scanned in approximately three minutes. This makes it much easier on the patient whose body rejects the dye, and the patient who is in a lot of pain.
• Ultrasound (sonogram): This is a painless and noninvasive test, but does not always catch small stones. An ultrasound machine uses computer processing and high-frequency radio waves to look at your internal organs.

Treatment

There are various ways of treating kidney stones. They focus on pain relief, hydration, and antibiotics (if any urinary infections are present). Your doctor will take into consideration several factors, including the type of stone, the cause of the stone, your medical profile, and the severity of the condition.

Sometimes simply drinking 3 quarts or more of water a day will disintegrate the stone, allowing it to pass without any medical intervention. (If you are aware that you are passing one, urinate through a strainer and take the stone to your doctor to have it analyzed.) Otherwise, you will have one of the following treatments:

• Extracorporeal shock wave lithotripsy (ESWL): This is the most common procedure used to treat kidney stones. Shock waves are sent directly to the stone to break it up into tiny pieces that can pass through the urinary system. There are two different machines used for this painless procedure. One requires the patient to be semi-submerged in a tub of water; the other is done with the patient lying on a table. Either way, earphones are required because every time a shock wave is generated, a loud sound is created. If the shock waves do not break it down small enough, one of the other procedures will follow.
• Percutaneous nephrolithomy (tunnel surgery): In this surgical procedure, a small cut is made in the back and a tunnel is made through the skin to the stone, and the stone is removed.
• Ureteroscopic stone removal: If the stone is located in one of the ureters (tubes that connect the kidneys to the bladder), it may be removed with an ureteroscope, a tube-shaped device with a camera that is inserted into the ureter. It is also equipped with a cage that retrieves the stone.
• Parathyroid surgery: The thyroid gland, located beneath the Adam’s apple, has four corners. At each corner, a parathyroid gland is located. When one of these glands becomes overactive, too much calcium is created, causing calcium stones. This is often because a parathyroid gland has a benign (non-cancerous) tumor. In this procedure, the tumor is removed.

Risk Factors

Kidney stones are one of the most common disorders of the urinary tract. It is estimated that in the United States, 1 in 10 will experience this painful condition at some time in their life. Some factors increase your chances of landing in that 10%.

• Age, Race, Sex: Kidney stones tend to appear in people between the ages of 20 and 40. Caucasians get them more often than African Americans, and men get them more often than women.
• Diet: A high protein (meat, chicken, fish), low fiber (whole grains, veggies, fruits) diet may increase your chances of certain stones.
• Fluid Deficiency: If you do not drink enough water, your urine is much more likely to have a higher concentration of stone-forming minerals. This is why you are more likely to get kidney stones in you live or work in a hot, dry climate and do not replenish your lost fluids.
• Medical History: If someone in your family has had stones, you are more likely to develop one. If you have already had one, there’s a good chance you might get another one. Certain diseases can also increase your risk, including but not limited to gout, chronic urinary tract infections, and cystic kidney disease.
• Medications: Certain medications can effect the development of kidney stones. Talk to your doctor about any medications you are taking. Some diuretics increase your risk, and sometimes diuretics decrease it.
• Sedentary Behavior: People who are not active for long periods of time are at a higher risk for calcium stones. Bones release more calcium when they are not being used.

Prevention

A review of the risk factors leads to only one conclusion. The things you can do to prevent kidney stones are things that you should do for your overall health anyway. There’s not much you can do about your age, race, sex, or medical history. There is limited control over the medications that you need. But you can watch your diet, you can choose to be active (there are exceptions here), and you can drink lots of water. So get to it.

If these things are not already part of your normal lifestyle, and you need some motivation to give you that jump start, find someone who has passed a kidney stone. Ask what it felt like to push a jagged stone through the same tube used for urination. If that doesn’t motivate you, nothing will.

Stay healthy and be good to your body, it puts up with a lot from you.