Samantha Warner-Grimsley, RN, BSN, CBN, works as a clinical nurse for Penn bariatric surgery patients. Since many patients worry about developing kidney stones after surgery, she explains what makes kidney stones form, symptoms and ways to prevent them.
After bariatric surgery, patients have an increased risk for kidney stones.
Research shows that gastric bypass patients have changes in urine and higher levels of particles, called oxalates, which form kidney stones. You see, the gastrointestinal (GI) tract naturally absorbs oxalate. However, once the GI tract is altered during surgery, higher levels of oxalate can occur in the urinary tract. The oxalate can form crystals, which may lead to the formation of kidney stones.
Symptoms of kidney stones include:
- Back pain
- Blood in the urine
- Nausea or vomiting
- Fever and chills
- Urine with a bad smell
- Cloudy urine
If you have symptoms of a kidney stone, contact your doctor or nurse practitioner. You may be asked to drink extra fluid to flush out the stone in the urine, and then strain your urine so that a stone can be sent to a lab for testing.
There are ways to prevent kidney stones from forming.
Drink lots of water
You’ve probably heard again and again from your dietician that you need to consume water throughout the day to help your body function, keep up with physical activity and keep the hunger at bay. In addition, proper hydration helps the body get rid of waste and keeps digestion on track.
Limit oxalate-containing food
Foods that contain oxalates include beets, spinach, rhubarb, strawberries, nuts, chocolate, tea, wheat bran and dry beans.
Reduce sodium intake
Reduce the amount of salt you eat, as well as red meat. Too much sodium can trigger kidney stones because it causes you to get dehydrated, and the minerals will crystalize when there is not enough fluid in the body to dilute them. It also may raise the level of calcium in your urine.
Because the GI tract will absorb less calcium (in addition to oxalate), a lot of people believe that a build-up could lead to kidney stones. In actuality, kidney stones have no relationship to calcium; the oxalate is really the problem. You need calcium in your diet, so make sure you keep taking your calcium supplements as directed.
If you have any questions about kidney stones or your diet, contact your doctor, nurse practitioner or bariatric dietitian.