Kidney Stones

Kidney stones and other renal causes of back and side pain are diagnosed and treated by the Urology Division of Premier Medical Group. Kidney stones (calculi) are hardened mineral deposits that form in the kidney. They originate as microscopic particles of crystals and develop into stones over time. The medical term for this condition is nephrolithiasis, or renal stone disease.

Crystals and kidney stones may form when an imbalance of minerals occurs in the urine. About 1 in 10 Americans will suffer from kidney stones in their lifetime. Historically, men have stones three times as often as women, but this ratio has decreased over the last decade.

What are kidney stones?

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Kidney stones (calculi) are hardened mineral deposits that form in the kidney. They originate as microscopic particles of crystals and develop into stones over time. The medical term for this condition is nephrolithiasis, or renal stone disease. Crystals and kidney stones may form when an imbalance of minerals occurs in the urine. About 1 in 10 Americans will suffer from kidney stones in their lifetime. Historically, men have stones three times as often as women, but this ratio has decreased over the last decade.

What causes kidney stones?

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Several factors increase the risk for developing kidney stones, including inadequate fluid intake and dehydration, reduced urinary volume, increased excretion of certain minerals in the urine (e.g., calcium, oxalate, uric acid) or decreased excretion of others (magnesium, citrate). Normally, a balance is kept in the levels of these minerals. An imbalance can cause crystals to form, which then bind together into kidney stones. These stones may be present for a long time before symptoms appear. Often, it’s only when the stone(s) move around in the kidney that back or side pain first appears.

Several medical conditions such as medullary sponge kidney, renal tubular acidosis, hyperparathyroidism, and urinary tract infections (UTIs) may contribute to kidney stones. Anything that blocks or reduces the flow of urine (e.g., urinary obstruction, congenital abnormalities) also increases the risk. For many Americans, our dietary habits play a very large role – particularly an excess of salt (sodium) and animal meat protein (beef, chicken, fish, pork, etc).

What are the symptoms of kidney stones?

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Kidney stones can be less than 2mm

The discomfort caused by kidney stones can be the most agonizing pain ever experienced by a person. Women often state that renal colic pain is worse than labor. The most common symptom is back and flank pain, which often starts between the ribs and hips and then radiates down to the groin. The side pain may move around with the stone, or it may let up altogether.

Other symptoms of kidney stones may include the following: blood in the urine, increased frequency of urination (urinary urgency), nausea and vomiting, pain during urination (stinging, burning), tenderness in the abdomen and kidney region.

Kidney stone complications include kidney damage and scarring, decreased kidney function, obstruction of the ureter, recurrent stones, infections, and renal colic (severe pain that radiates from the kidney region to the abdomen and groin).

How are kidney stones diagnosed?

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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.

What else causes back and side pain that moves around?

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It’s difficult to fully account for all the conditions, especially less common ailments, that may cause back and/or side pain that moves around. Plus, many conditions can present with different symptoms, especially at first. Rather than assuming that side pain must be a kidney stone that will pass, consider whether the symptoms might be caused by a different medical condition.

Infections: Urinary tract infections and kidney infections can cause lower abdominal and side pain that moves around. However, it’s more common for a lower UTI infection to spread upward to the kidneys, while kidney stones start in the kidney before being passed through the ureter.

Other Renal Disease: Kidney stones and kidney infections are by far the most common types of renal (kidney) disease, but there are others. Large kidney cysts are one possibility. Other medical illnesses or physical injury can cause kidney damage which results in pain and reduced function.

Pancreatitis: This often starts as upper left abdominal pain and will tend to move toward the back as the condition worsens. While bowel movements may be discolored, most of the pain tends to stay higher and move laterally.

Appendicitis: This pain typically starts in the middle abdomen and will move lower as the condition progresses. While kidney stones usually start with side pain, appendicitis pain is more likely to start at the navel and then move to the lower right side. Like a kidney stone that moves and stops hurting, appendicitis pain can also subside suddenly. However, this is not a good sign as it could indicate the appendix has burst, and emergency care must be sought immediately.

Other common conditions that involve side and back pain include peptic ulcers, diverticulosis, constipation, and delayed gastric emptying. Moreover, not all back and side pain that moves around is related to urological or GI conditions. While recovering from a back strain, other muscles tend to compensate which can lead to musculoskeletal soreness in other areas.

What are the different types of kidney stones?

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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.

How long does it take for a kidney stone to pass?

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Many kidney stones pass within several weeks. Stones less than 4 millimeters wide often pass without the need for surgical intervention. Stones between 4-6 millimeters have closer to 50/50 odds of passing on their own and may take months to do so. Stones larger than 6 millimeters may sometimes pass on their own after as much as a year, but these larger stones more frequently require medical treatment.

How to help a kidney stone pass?

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The best thing you can do to help a kidney stone pass is to drink lots of water and/or citrus juice. Orange, grapefruit, and even lemon juice are commonly recommended. Look to drink at least 2 or 3 quarts per day to increase urination and encourage the kidney stone to pass. You should also take steps to prevent the kidney stone from growing any larger. Minimize the salt, calcium, and protein in your diet. Consult with your doctor to determine safe levels for your diet.

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. Pain killers, such as non-steroid anti-inflammatory drugs, won’t help the kidney stone pass but are still commonly recommended for pain management.

How are kidney stones treated?

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Extracorporeal shockwave lithotripsy (ESWL), or “blasting” of the stones, is a popular 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.

For kidney stones that don’t pass on their own, 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. They see patients in the Poughkeepsie and Kingston locations.

How do you prevent kidney stones?

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Once you’ve had one kidney stone, it’s more likely you’ll have a second kidney stone. The best prevention against future kidney stones is following your physician’s treatment plan. This could mean more regular checkups, 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