The Center for Kidney Stones Disease at Medstar Georgetown University Hospital has more than 30 years of experience treating the most complicated kidney stone patients in the metropolitan area. We offer patients prompt evaluation and effective treatment options, including medical support to help patients pass stones spontaneously when possible. We also provide the most advanced technology to help remove stones when surgical treatment is necessary. When the acute event is resolved, we offer effective medical evaluation to help patients define the causes of their stone formation to help prevent stone recurrences.
New technologies help doctors manage kidney stones. Imaging studies help doctors diagnose stones quickly and reliably, before kidney damage happens. Modern surgery for stones is effective, minimally invasive and often performed as an outpatient procedure. Medications and diet advice can prevent stones from growing or returning. Better diagnosis, treatments and prevention mean quick recovery and fewer repeat episodes.
Kidney stones, solid deposits of mineral and acid salts that build up inside the kidneys, are relatively common – more than one million Americans are hospitalized every year with this condition, and approximately 10 percent of people in the United States will have a kidney stone sometime in their life.
Risk Factors for Kidney Stones Include
- Whites are more likely to develop kidney stones than African Americans or other races.
- Men are more likely than women to have stones, but the number of women with stones has gone up in the past ten years.
- This may be connected to the rise in obesity in women compared to men, as obesity is a known risk factor for kidney stones.
Types of Kidney Stones
- The most common stone composition is calcium oxalate. These stone can also have a small percentage of calcium phosphate.
- Patients with recurrent urinary tract infections may have stones made of magnesium ammonium phosphate (struvite). The bacteria in the urine cause the urine pH to become basic and this causes the stone salts to precipitate out rapidly and these stones can become large and fill the kidney ( they may look like a dear antler).
- Less common stone composition include uric acid stones in about 8 to 10 percent of patients and even less common are stones composed of cystine. This is an amino acid one of the building blocks of proteins and they tend to develop in children around the onset of puberty.
Symptoms of Kidney Stones
If a urinary stone is in the kidney and not blocking the passage of urine it may not cause symptoms. Blood may be found in the urine during a routine urine exam ( urinalysis) and may suggest the presence of a urinary stone. Stones that are associated with urinary tract infection may be found when looking for causes of persistent UTI. Most stones that pass out of the kidney are 4 mm in size( about the size of the head of a match). This size stone causes blockage of urine flow when it enters the ureter and causes a rapid swelling ( hydronephrosis) of the kidney. Symptoms may include:
- sharp, cramping pain in the back and side, often moving to the lower abdomen or groin. Some say the pain is worse than childbirth labor pains. The pain often begins suddenly and comes in waves. It can come and go as the body tries to get rid of the stone.
- nausea and vomiting
- a feeling of an intense need to urinate
- abnormal urine color or appearance
- if fever or chills are present with any of these symptoms, an infection may be present, and you should see your doctor immediately.
As stones pass out of the body they irritate the lining of the urinary tract and cause visible blood in the urine in 25 percent of patients and blood that is found on lab analysis (microhematuria) in 95 percent of patients.
Since most stones contain calcium, they can be seen on a plain abdominal x-ray film called a KUB (kidney, ureter, bladder). Stones with a uric acid or cystine composition may be difficult to see on a KUB and many patients will need a sonogram or CT to confirm the diagnosis
Kidney Stone Prevention
The first step in starting to do the medical evaluation to prevent more stone events is to have a complete medical history and physical. This will include looking for risk factors for stone recurrence. Having a family history of kidney stones may increases your risk. A personal history of frequent diarrhea, or inflammatory bowel problems, gout, urinary tract infection are all risk factors for stone recurrence. Knowing your eating habits is also helpful because you may be eating foods that are known to raise the risk of stones or may not be drinking enough fluids or eating the foods that protect against stone formation.
Testing for Kidney Stones
- Stone analysis (important for first time stone former)
- Blood studies (evaluate calcium, phosphate, uric acid, electrolytes, creatinine)
- 24-hour urine collection (to evaluate urinary risk factors) on current diet and then repeat if needed on a stone diet to reduce abnormal findings
- Additional imaging to evaluate for stone recurrence during routine follow up.