Diagnosis of Kidney Stones

Diagnosis of renal stone disease involves a medical history, physical examination, laboratory evaluation, and imaging tests. Fever may indicate a urinary tract infection that requires antibiotics. Laboratory tests include a urinalysis to detect the presence of blood (hematuria) and bacteria in the urine. Other tests include blood tests for creatinine (to evaluate kidney function), BUN and electrolytes (to detect dehydration), calcium (to detect hyperparathyroidism), and a complete blood count (CBC; to detect infection). Radiographic imaging is very important to assess the location and size of the stone(s) as this information will have a great impact on the treatment options. Imaging options include: Ultrasound, plain radiographs (KUB, IVP) and more commonly a CAT scan without any intravenous contrast.

Types of Kidney Stones

Calcium Stones (calcium oxalate or calcium phosphate): These are the most common type of stones (70%) and can form due to fluid and dietary habits. Some patients inherit a tendency to make stones from their parents. These stones are becoming more common as Americans gain too much weight.

Uric Acid: These stones can be associated with gout and with an excess of animal meat intake. These are the only stones that can be dissolved while still in the body.

Struvite Stones: These are also called infection stones and are caused by infection in the urinary tract (UTI). They are made of magnesium, ammonia, and phosphate. Bacteria in the urinary tract release chemicals that neutralize urinary acid, which enables bacteria to grow more quickly and promotes struvite stone development.

Cystine Stones: These are caused by cystinuria, an uncommon genetic disorder. Cystine is an amino acid in protein that does not dissolve well. This condition (called cystinuria) causes cystine stones that are difficult to treat and requires life-long therapy.

Prevention of Kidney Stones
The best prevention against future kidney stones is following you physician's treatment plan. This could mean more regular check ups, and further testing. It could also mean taking medication.

Some further testing may include:

  • 24-hour urine sample
  • Blood tests to check for mineral samples
  • Stone analysis to determine the composition of a passed stone

Drinking lots of fluids, especially during warmer weather, can help flush minerals out of your kidneys before they can build up and form stones. Two quarts of fluid daily, preferably water, can really help. Try to keep a bottle of water with you during the day. Drink a glass of water with meals, and when you brush your teeth.

The color of your urine can be a helpful indicator of dehydration. Clear or light yellow means you are drinking enough, while dark yellow urine means you should drink more fluids.

Eating a healthy diet can help maintain normal levels of minerals in your urine.

  • Avoid excessive amounts of vitamin C.
  • Make sure to incorporate the recommended amount of calcium into your daily diet. Too little or too much can affect your chance of kidney stones.
  • Maintain a healthy weight. Obesity can lead to kidney stones.
  • Limit salt intake, fatty foods, and animal protein.
  • Avoiding foods such as beets, spinach, rhubarb, black tea, and colas can also help.

Preventative Medications

  • Allopurinol: helps reduce the amount of uric acid in the urine
  • Potassium citrate: helps prevent calcium stones. Also helps dissolve uric acid stones
  • Thiazide diuretic: helps reduce the amount of calcium in urine

Treatment for Kidney Stones
Many kidney stones pass within several weeks. Stones less than 4 millimeters wide often pass without the need for surgical intervention.

Medications may be used to help pass your stones. Alpha-blockers, such as Flomax, are used most often for this purpose, as they help relax and dilate the ureters. Medications can also be used to dissolve uric acid stones.

Minimally invasive treatments include:

  • Ureteroscopy and Holmium Laser: A small telescope is passed through the bladder and into the ureter where a powerful laser can fragment even the hardest stones. This procedure is performed in the operating room, typically as a same day surgery.
  • Shock Wave Lithotripsy: A machine generates sound waves that pass through the body and focus on the kidney stones. This energy breaks the stone into small sand-like pieces, which generally pass through the urine. General anesthesia is used, and you'll likely go home the same day.
  • Percutaneous Stone Extraction: This is used for larger stones in the kidney. A small incision is made in your back, a telescope with camera is inserted into the kidney and stone fragments are removed. Most patients stay in the hospital a day or two and return to work shortly thereafter.
  • Metabolic Evaluation: All patients are encouraged to make fluid and dietary changes that will help decrease repeat stone risk. Many patients will also be asked to take simple urine and blood tests that will more accurately explain why they are making stones. This information helps tailor an individual treatment plan.


Dr. Evan Goldfischer and Dr. Paul Pietrow both specialize in the treatment of kidney stones. Dr. Goldfischer sees patients in the Poughkeepsie office, and Dr. Pietrow sees patients in the Kingston office.