(Extraído de Nih record)
By Jan Ehrman
Talk about a summer bummer. They could attack you, fully unprovoked—like bees pouring out of a hornet’s nest—during your daughter’s graduation ceremony, in the middle of your family picnic or during the 7th inning stretch. Their pain can bring you to your knees. In fact, just the thought of them is enough to make a person wince—kidney stones.
There’s never a good time for these unwelcome intruders, but evidence shows they inflict their pain most often during the humid, oppressive summer months, when dehydration can most frequently occur and there is increased outdoor activity. They also crop up more often in southern parts of the country and, internationally, in regions close to the equator.
Often described as comparable to, and perhaps even more painful than, natural childbirth, kidney stones—known as renal calculi—are solid, often sharp substances made of mineral and acid salts. They can travel into the ureter (the tube connecting the kidney and bladder), dishing out excruciating lower back pain and genital discomfort. In addition, the afflicted may also experience bloody urine, fever and chills, nausea and vomiting and, most frequently, a constant urge to urinate.
Kidney stones—known as renal calculi—are solid, often sharp substances made of mineral and acid salts. They can travel into the ureter (the tube connecting the kidney and bladder), dishing out excruciating lower back pain and genital discomfort. In addition, the afflicted may also experience bloody urine, fever and chills, nausea and vomiting and, most frequently, a constant urge to urinate.
Experts note that the stone may vary in size and can be as small as a grain of sand or as large as a pearl. The smaller they are, the more likely they can pass through the system naturally, without medical treatment.
According to the National Institute of Diabetes and Digestive and Kidney Diseases, more than 3 million patients (more men than women) or nearly one person in 8 will see their primary care physician or urologist annually for kidney stones, while another half million will visit their local emergency room seeking relief. Viewed another way, one in 300 persons in the U.S. will experience a kidney stone in any given year.
Meanwhile, the disorder is a major contributor to morbidity and loss of time from work. And unfortunately, it may not be a one-time thing. Experts say that once you’ve had a stone, you have a 50 percent chance of developing another one within the next 5 years. This risk generally increases with advancing age.
Stones can create havoc in a number of ways, says one authority.
“While we really do not know the exact mechanism for why humans develop kidney stones, what we do know for certain is that these stones inflict a tremendous amount of misery and suffering for the individual and, for the nation as a whole, much economic distress,” said Dr. Ziya Kirkali, senior scientific advisor to NIDDK’s Division of Kidney, Urology and Hematology. He added that more than $2 billion is spent in the U.S. each year for treatment of the malady.
According to Kirkali, the pain of kidney stones occurs when the ureter contracts in an attempt to pull the stone through the bladder tube. If the surface of the stone is sharp or pointed, as is often the case, it unleashes a nagging or stabbing discomfort in the lower back and/or groin.
Heritability does not appear to be a cause of kidney stones, but time of year is associated with its occurrence.
What is almost beyond question, authorities maintain, is that we do not drink enough liquids, especially water, a fact that rings particularly true during the summer months, when we lose body fluid through perspiration and fail to replace it.
“Someone who is particularly at risk for stones [a “stone-former”] should be drinking at least 12 glasses of water each day, especially during the summer,” Kirkali said. “This helps dilute your body liquids, as well as calcium oxalate, the substance that makes up most types of renal stones. Drinking enough water is really critical for preventing the development of stones. Further,” he advises, “you cannot afford to let yourself get dehydrated in the summer.”
While some say lemonade can help circumvent the problem, the NIDDK expert thinks water is the superior drink. “It’s your great protection against the development of kidney stones,” Kirkali said.