Kidney stones, one of the most painful of urologic disorders, are not a product of modern life. Scientists have found evidence of kidney stones in a 7,000-year-old Egyptian mummy.
Unfortunately, kidney stones are a common disorder of the urinary tract. Most kidney stones pass out of the body without any intervention by a physician, but stones that cause lasting symptoms or other complications can be treated by various techniques, most of which do not involve major surgery.
The specialists at Summit Health offer the latest in surgical and non-surgical techniques for the treatment of stone disease. After a thorough evaluation, our experienced urologists will create an effective treatment plan tailored to meet each patient’s individual needs.
What is a kidney stone?
A kidney stone is a hard mass developed from crystals that separate from the urine and build up on the inner surfaces of the kidney. Normally, urine contains chemicals that prevent or inhibit crystals from forming. However, these inhibitors do not seem to work for everyone, causing the formation of stones. If the crystals remain tiny enough, they will travel through the urinary tract and pass out of the body in the urine without being noticed.
Kidney stones may contain various combinations of chemicals. The most common type of stone contains calcium in combination with either oxalate or phosphate. These chemicals are part of a person’s normal diet and make up important parts of the body, such as bones and muscles.
Who gets kidney stones?
The number of people in the United States with kidney stones has been increasing over the past 30 years. Currently, the prevalence of kidney stones is 8.8% and affects approximately 1 in 11 people in the United States.
Stones occur more frequently in men. The prevalence of kidney stones rises dramatically as men enter their 40s and continue to rise into their 70s. For women, the prevalence of kidney stones peaks in their 50s. Once a person gets more than one stone, others are likely to develop.
What causes kidney stones?
In general, kidney stones form when there is a decrease in urine volume or an excess of stone-forming substances in the urine. 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.
Dehydration through reduced fluid intake, or strenuous exercise without adequate fluid replacement, increases the risk of kidney stones as well as obstruction to the flow of urine. A number of different conditions can lead to kidney stones, such as:
- Gout
- Hypercalciuria (high calcium in the urine)
- Hyperparathyroidism
- Kidney diseases such as renal tubular acidosis and some inherited metabolic conditions (i.e., cystinuria and hyperoxaluria)
- Inflammatory bowel disease (IBS)
Some medications also raise the risk of kidney stones. These medications include:
- Diuretics
- Calcium-containing antacids
- Crixivan which is a prostate inhibitor
Risk factors for developing kidney stones include:
- A diet high in protein, sodium, and sugar
- Dehydration
- Digestive diseases, such as irritable bowel syndrome
- Family or previous personal history of kidney stones
- Obesity
- Undergoing gastric bypass
Treatment for kidney stones varies depending on the type of stone and its cause. However, the majority of kidney stones do not require invasive treatment. Smaller stones may be passed by drinking water or by taking pain receivers or prescribed medications.
Larger stones and stones that cause more severe symptoms may be treated with shock wave therapy to break them up, removed through a surgical procedure known as a percutaneous nephrolithotomy—a minimally invasive procedure performed through a small incision made in the back where the stone is removed) or broken up/removed using a scope.
When is Surgery Required?
There are different therapies for treating kidney stones:
- Conservative therapy
- Medical therapy
- Surgical therapy
Most kidney stones eventually pass through the urinary tract on their own within 48 hours, with ample fluid intake. As a result, the conservative therapy approach may prescribe pain medication for symptom relief and recommend taking an alpha blocker medicine such as Flomax/Tamsulosin to help distal stones (closer to the bladder) pass.
There are several factors that influence the ability to pass a stone including:
- Size of the stone
- Prior stone passage
- Prostate enlargement
- Pregnancy
Medical therapy uses certain drugs and/or lifestyle changes to help dissolve stones. These medicines can take months to work and are only useful with uric acid stones.
- Does not pass after a reasonable period of time
- Causes constant pain
- Is too large to pass on its own or caught in a difficult place
- Blocks the flow of urine
- Damages kidney tissue
- Causes constant bleeding
Various surgical options and the latest innovations are now available to patients with kidney stones, including ESWL, Ureteroscopic Stone Removal, and Laser Lithotripsy.
- ESWL (Extracorporeal Shock Wave Lithotripsy - Uses shock waves that are created outside the body and travel through the skin and body tissues until they hit the denser stones. The stones break down into sand-like particles and are easily passed through the urinary tract in the urine. In most cases, ESWL may be done on an outpatient basis, and recovery time is short. Most people can resume normal activities in a few days.
- Ureteroscopic Stone Removal and Laser Lithotripsy - In this procedure, the surgeon passes a small fiberoptic instrument called a ureteroscope through the urethra and bladder into the ureter. The surgeon then locates the stone and either removes it with a basket or fragments it using a laser. A small tube or stent may be left in the ureter for a few days to help the lining of the ureter heal.
Bladder stones
Bladder stones are hard mineral deposits that form in the bladder when urine in the bladder becomes concentrated, resulting in crystallized minerals. The stones are generally due to the bladder’s inability to fully empty.
Risk factors for developing bladder stones include:
- An obstruction blocking the flow of urine from the bladder to the urethra
- Being male and over the age of 30
- Damage to the nerves that control bladder function due to disease (e.g., Parkinson’s disease) or trauma (e.g., spinal cord injury)
In practically all cases, bladder stones must be removed. Treatments include:
- Cystolitholapaxy — breaking the stones and removing the pieces through the use of a scope inserted through the urethra and into the bladder
- Open surgery — an incision is made directly in the bladder and the stones are removed
Ureteral stones
Ureteral stones are hard mineral deposits that can originate in the kidney and move to the urinary tract, or form in the tract itself. The risk factors for developing ureteral stones are the same as kidney stones with one additional factor: they may also form due to a urinary tract infection. In addition, because of the similarity between the two types of stones, treatment methodologies are also the same.