Kidney stones can grow silently for years. But once the stones become large enough to pass the narrow tubes in your kidneys, the writhing agony is said to be comparable to that in labor.
August 20, 2013, 8:00 AM
Kevin woke up in pain. He hasn't felt this kind of discomfort since 2011, only this time, the pain is radiating from the left part of his back, just below his waist. He was still able to stand and walk, albeit slowly, towards the bathroom. After 30 minutes, the pain becomes tolerable and subsides without any treatment. So Kevin proceeds with his usual morning routine.
August 23, 2013, 12:00 PM
He hasn’t been drinking large quantities of fluid, but Kevin had frequent bathroom visits today. He noted pain at the end of his urination. The urine is faint pink in color. Kevin thought the pain and color were related to his recent preference for beet salad.
August 27, 2013, 9:00 PM
Kevin felt pain emanating from his back and cannot get up. The sensation made him sick to his stomach and nauseous. Then he blacked out. Kevin was rushed to the hospital.
In this given scenario, you might think Kevin must be overreacting to a simple urinary tract infection. The answer is no. Anything that can painfully obstruct the urinary tract demands immediate medical attention. Kidney stones are serious.
Down the drain: Urinary tract as a built-in drainage system
To recap: the urinary tract performs an essential function for the human body. It facilitates the excretion of bodily wastes and extra water. The kidneys filter the unwanted material from the blood to produce urine. The urine flows through the ureters to the urinary bladder, where urine is collected and expelled during urination. If the urine filters excessive wastes and there is a lack of water, the urine becomes more concentrated. This is the most common instance when kidney stones develop.
Kidney stones: the (un)precious crystals
Nephrolith (nephro, kidney + lithos, stone) is a miniscule deposit made from different materials, most of which are from minerals filtered by the kidneys from the body. These stones form when the urine gets concentrated. For easier visualization, imagine salt crystals. Saltwater interacts with minerals and dissolves them. If the saltwater evaporates, minerals will precipitate and salt is formed.
Kidney stones are often as small as a grain of sand (less than 5 mm). These can easily pass out in the urine without causing discomfort. However, when the deposits become the size of a pea, a marble, or even larger (more than 7mm), these stones may travel up and down the urinary tract and get stuck. These can be a source of a myriad of health problems, including blockage of the ureters (the tube that connects the kidneys to the urinary bladder) and lower back pain during stone passage called renal colic. The colic typically lasts from 30 minutes to an hour and can radiate from the upper abdomen all the way to the groin area. Sounds painful enough? We’re not quite finished yet.
A key indicator of renal colic is the pain that comes in waves: The pain slowly subsides then shoots back again. Think of big ocean waves hitting a tanker ship over and over again. If the wave is strong and big enough, the ship might topple over. The pain caused by kidney stones can be repeatedly excruciating, causing a person to pass out just like Kevin.
Aside from the usual symptoms of lower back pain and discomfort, those suffering from kidney stones may also experience urinary tract infection-like symptoms such as sweating, nausea, vomiting, and fever. More common urinary symptoms include hematuria (blood in the urine), difficult and painful urination, and urinary urgency.
You're a (kidney) stone's throw away from getting one
Kidney stone is a common problem in primary care practice. In 2013 alone, there were about 49 million reported cases of kidney stones. In the Philippines, an estimated 10% of the population will have a kidney stone at some point in their life. Young adults, those aged 20 to 40 years old, are more prone to develop them than any other age groups.
Men are two to three times higher at risk to get kidney stone, presumably because of their failure to drink water for adequate rehydration after sweating. There is a 50% chance that kidney stones will recur in 5 to 10 years, and increase up to 75% in 20 years.
To the great surprise of parents, kidney stones are now showing up in children as young as 5 or 6 years old. While there are no reliable data on the number of cases, experts are seeing a steep rise in young patients. For example, the children who drank milk tainted with melamine (a toxic chemical illegally added to watered-down milk to inflate the protein count) in China developed kidney stones. The increase in numbers in the United States is attributed to a host of factors, including a food additive that is both legal and ubiquitous: salt.
Obesity is also a factor. In a recent study conducted by Dr. Brian Matlaga and his colleagues at John Hopkins Hospital, obese and overweight people are more susceptible to have kidney stones than those with normal weight.
Kidney stone causes: leaving no stone unturned
Like most health problems, the formation of kidney stones is due to two major factors: heredity and lifestyle. Studies have shown that people whose parents experienced kidney stones during their lifetime are more predisposed to develop them as well.
Lifestyle and environmental factors also play a huge part in kidney stone formation. This is due to the fact that kidney stones can form not only from a single substance, but can be caused by several materials such as accumulated and excess calcium, oxalates, phosphates, and uric acid. A stone's color, shape, and size can help determine the type of stone formed.
Several day-to-day activities can also contribute to the formation of kidney stones. Low total fluid intake is a major culprit in the formation of the stones since urine would tend to get more concentrated. Water plays a big part in the dilution of the urine which in turn inhibits the accumulation of the substances that causes kidney stone formation. Next time you eat that salty snack, be sure to adequately hydrate after!
Diet is also a major contributor. Meat lovers, beware: High animal protein intake tends to increase the risk of kidney stone formation. Animal protein, especially beef and pork, contains uric acid. Excessive intake can cause disproportionate levels of uric acid in the body which may lead to kidney stone formation. Furthermore, increased consumption of sodium and refined sugars are also linked to the formation of kidney stones since they make urine more concentrated.
The US National Institute of Diabetes and Digestive and Kidney Diseases lists out several other factors that may increase the risk of kidney stone formation. Several common factors are as follows:
• Gout – a metabolic disease wherein uric acid builds up in the blood and is not excreted by the body. Uric acid usually crystallizes in the joints causing pain and swelling. When the uric acid crystals are deposited in the kidneys, they usually become large and painful kidney stones.
• Existing blockage in the urinary tract, especially previously untreated kidney stones.
• Pre-existing kidney diseases can also contribute to the formation of the stones.
• Other conditions at risk for developing stones are as follows: parathyroid disease, gout, bowel disorders, and intestinal surgery.
Medications may also play a role in the formation of kidney stones. Individuals prescribed with diuretics have an increased risk. Diuretics are medications that help the kidneys draw water from the body, which may eventually lead to more concentrated urine if not proper precautions are taken.
It is vital and essential to take note of these contributing factors in developing kidney stones as they can help us assess the risks of having one in the future. Remember, an ounce of prevention is better than a pound of cure.