Former presidential candidate turned New York City mayoral candidate Andrew Yang, 46, was hospitalized briefly last week with a kidney stone. The tech entrepreneur's campaign released a statement saying: "After experiencing abdominal pain this morning, Andrew Yang visited an emergency room where he was diagnosed with what appears to be a kidney stone."
Later that day, Yang : "Thank you to the team at Mt Sinai West for the excellent care! And thanks Evelyn [his wife] for keeping me company as I experienced my first (and hopefully last) kidney stone. Have been discharged and will now proceed to drink lots of water for the rest of the day."
While at the hospital, Evelyn Yang : "In the hospital with Andrew where we had our babies. Andrew is doing well on meds, with the best care team ever. We are joking about how this kidney stone is our third baby. Apparently, it's the closest men can get to labor."
Kidney Stones
Kidney stones are hard, pebble-like pieces of material that form in the kidneys when high levels of certain minerals collect in the urine. These crystal concretions are usually formed within the kidneys. The scientific names for kidney stones include renal calculus, nephrolith, or urolith. Approximately 12% of the world's population is affected by kidney stone disease.
Kidney stones vary in size and shape. They may be as small as a grain of sand or as large as a pea. Rarely, some kidney stones are as big as golf balls. Kidney stones may be smooth or jagged and are usually yellow or brown.
There are four main types of kidney stone:
Calcium stones, including calcium oxalate stones and calcium phosphate (also called apatite) stones, are the most common types of kidney stones, with calcium oxalate stones being more common than calcium phosphate stones. Calcium stones comprise nearly 80% of all renal stones.
Several factors contribute to calcium oxalate stone formation. These include any condition that leads to excess calcium, uric acid, or cystine, or low levels of magnesium or citrate in the kidney or urine. Acidic urine (pH 5.0-6.5) tends to lead to calcium oxalate stone formation, whereas calcium phosphate stones occur in urine with a pH greater than 7.5.
Dietary calcium does not increase the incidence of calcium oxalate stones. Calcium binds to oxalates found in foods- keeping it in the intestines and preventing absorption from the gut.
Uric acid stones form when the levels of uric acid in the urine is too high, and/or the urine is too acidic (pH level below 5.5) on a regular basis. Acidic urine can be caused by inherited problems that involve how the body processes uric acid or protein (such as gout). It can also be caused by a diet high in purines, found in animal proteins such as beef, poultry, pork, eggs, and fish. The highest amounts are found in organ meats like liver and fish including anchovies, sardines, herring, mussels, codfish, scallops, trout, and haddock. Others at increased risk of urate stones are those who are obese, have diabetes, or on chemotherapy.
Struvite stones occur in about 10-15% of those with stones. They are sometimes referred to as "infection stones" or "triple phosphate stones." They occur most commonly in patients with chronic urinary tract infections with organisms that produce urease. The most common pathogens include Klebsiella pneumonia, Pseudomonas aeruginosa, and Enterobacter.
Increased levels of urease cause the urine to become more alkaline. At the higher pH, phosphate precipitates on insoluble ammonia in the urine, forming staghorn stones. Women are more likely than men to have this type of stone.
Cystine stones comprise less than 2% of kidney stones. They result from a genetic disorder called cystinuria. Cystinuria causes the amino acid cystine to leak through the kidneys and into the urine.
Symptoms
A small kidney stone may pass through the urinary tract on its own, causing little or no pain. A larger kidney stone may get stuck anywhere along the way from the kidney to the urethra. The latter can block the flow of urine, causing symptoms such as:
- Sharp pain in the back, side, lower abdomen, or groin
- Pink, red, or brown blood in the urine (hematuria)
- Constant need to urinate
- Pain while urinating
- Inability to urinate or the ability to only urinate a small amount at a time
- Cloudy or bad-smelling urine
The pain may last for a short or long time or may come and go in waves.
Other symptoms include:
- Nausea
- Vomiting
- Fever
- Chills
Treatment
Kidney stones are treated based on their type, size, and location.
Small kidney stones may pass through the urinary tract without treatment. If possible, the stone should be collected and sent to the lab to determine its type. Larger kidney stones and those that block the urinary tract or cause great pain may need urgent treatment.
A urologist can remove the kidney stone or break it into small pieces with the following treatments:
Shock wave lithotripsy. The doctor can use shock wave to blast the kidney stone into small pieces. The smaller pieces of the kidney stone then pass through the urinary tract.
Cystoscopy and ureteroscopy. During , the doctor uses a cystoscope to look inside the urethra and bladder to find a stone. During ureteroscopy, the doctor uses a ureteroscope, which is longer and thinner than a cystoscope, to see detailed images of the lining of the ureters and kidneys. Once the stone is found, the doctor can remove it or break it into smaller pieces.
Percutaneous nephrolithotomy. A procedure, called is done when a doctor uses a thin viewing tool, called a nephroscope, to locate and remove the kidney stone. The doctor inserts the tool directly into the kidney through a small cut made into the back. For larger kidney stones, the doctor also may use a laser to break the kidney stones into smaller pieces.
After these procedures, the urologist, on occasion, may leave a thin flexible tube, called a ureteral stent, in the urinary tract to help urine flow or a stone to pass. Once the kidney stone is removed, the doctor sends the kidney stone or its pieces to a lab to find out what type it is.
A 24-hour urine collection after the kidney stone has passed can measure how much urine is produced/day, along with mineral levels in the urine. These can lead to a more accurate treatment and prevention plan.
Prevention
For those without renal failure, drinking enough liquid, mainly water, is the most important thing you can do to prevent kidney stones.
Diet may reduce the risk of kidney stones. Making changes in how much sodium, animal protein, calcium, or oxalate is in the food eaten may prevent kidney stones. For instance, studies have shown that the (DASH) diet can reduce the risk of kidney stones and has been by the National Kidney Foundation.
According to , "For prevention of calcium oxalate, cystine, and uric acid stones, urine should be alkalized by eating a diet high in fruits and vegetables, taking supplemental or prescription citrate, or drinking alkaline mineral waters. For uric acid stone formers, gout needs to be controlled, and for cystine stone formers, sodium and protein intakes need to restricted. For prevention of calcium phosphate and struvite stones, urine should be acidified. For struvite stones, acidifying the urine is the single most important step. Patients must receive careful follow-up to be sure that the infection has cleared."
Michele R. Berman, MD, and Mark S. Boguski, MD, PhD, are a wife and husband team of physicians who have trained and taught at some of the top medical schools in the country, including Harvard, Johns Hopkins, and Washington University in St. Louis. Their mission is both a journalistic and educational one: to report on common diseases affecting uncommon people and summarize the evidence-based medicine behind the headlines.