Kidney stones can be one of the most painful surgical disorders. They have been known to be around for years, scientists have found evidence of kidney stones in a 7,000-year-old Egyptian mummy. Unfortunately, kidney stones are one of the most common disorders of the urinary tract.
Condition – Kidney Stones
Most kidney stones pass out of the body without any intervention by a physician. Stones that cause lasting symptoms or other complications may be treated by various techniques, most of which do not involve major surgery. Also, research advances have led to a better understanding of the many factors that promote stone formation.
Who Gets Stones
About 5-10% of people will have a kidney stone at some time, although not everyone suffers from the symptoms. Men tend to be affected more frequently than women but recent evidence suggests that the incidence of stones in women is rapidly increasing.The prevalence of kidney stones rises dramatically as men enter their 40s and continues to rise into their 70s. For women, the prevalence of kidney stones peaks in their 50s, although this age is rapidly decreasing. Once a person gets more than one stone, others are likely to develop.
Why Do They Form
A kidney stone develops 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 the crystals from forming. These inhibitors do not seem to work for everyone, however, so some people form 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.
Doctors do not always know what causes a stone to form. 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.
A person with a family history of kidney stones may be more likely to develop stones. Urinary tract infections, kidney disorders such as cystic kidney diseases, and certain metabolic disorders such as hyperparathyroidism are also linked to stone formation.
In addition, more than 70 percent of people with a rare hereditary disease called renal tubular acidosis develop kidney stones.
There are 4 common types of kidney stones:
Of the four main types of urinary stones, calcium stones are the most common. Almost 80% of all kidney stones are calcium stones. They occur when there is too much calcium in the urine. Defective kidney function may allow too much calcium in the urine, or excessive calcium may be absorbed from the stomach and intestines.
Some calcium stones are caused by an excess of a chemical called oxalate, present in many foods, which binds easily with calcium to form a stone. The risk of calcium stone formation is increased if you have certain medical diseases; for example, hyperparathyroidism and inflammatory bowel disease.
- Uric Acid
A second type of kidney stone is made of uric acid. These stones are much less common than calcium stones. Uric acid stones occur because you have too much uric acid in your urine. They might occur if you have become dehydrated; for example, during strenuous exercise on a hot day or perhaps during an illness. Uric acid stones are common in people who have gout, a disease that causes high uric acid levels in the blood.
- Infection Stones (Struvite)
A third type, struvite stones, are not quite so well understood. It is thought that these stones form as a result of an interaction between protein-breakdown products and infection-causing bacteria in the urine.
Finally, a rare type of kidney stone is a cystine stone. It occurs if you have the genetic disease called cystinuria. This disease results from a birth defect that causes the kidney to allow too much cystine into the urine. This type of stone formation is almost always diagnosed during childhood.
How Are They Found
The stones are found by accident by routine examination with x-rays, or urine tests. Depending on whether they are causing problems, they may or may not require treatment.
- Signs / Symptoms:
- Pain – Usually, the first symptom of a kidney stone is extreme pain, which occurs when a stone acutely blocks the flow of urine. The pain often begins suddenly when a stone moves in the urinary tract, causing irritation or blockage. Typically, a person feels a sharp, cramping pain in the back and side in the area of the kidney or in the lower abdomen. Sometimes nausea and vomiting occur. Later, pain may spread to the groin.
- Blood in the urine