A Urologist's approach for a common problem. Dr Fadi Eliya summarizes treatment and approach to kidney stone disease

Thu, 30 Sep 2010 12:01:19 MDT

Kidney stones can be a significant cause of pain and grief for patients that suffer from this disease. Not only can kidney stones cause suffering and lost work time, but also can be life threatening in some situations. Kidney stones can cause pain, bleeding, infections, and obstruction of the kidneys which in turn can cause kidney failure. A urologist specializes in kidney stone management and treatment. People have a lifetime risk of 7-13% of developing kidney stones. Up to 50% of first time stone formers can have a recurrence at 5 years if they are not treated. Most stones are calcium based, but can be a combination of calcium and other constituents. Risk factors for stones include dietary, genetic, medication related, or geographic. Many times, the cause of the stones cannot be found. However, many reversible causes of stone formation can be elicited from a work-up and can save a person substantial relief from the potential complications of kidney stones. Stones can be asymptomatic and usually are found on work-up or imaging of an unrelated cause. However, pain is the most common symptom and can range from mild to severe requiring hospitalization. This pain is usually due to obstruction of the kidney and can be associated with fevers, blood in the urine, nausea and vomiting. The location of the stone determines the area of the pain which can radiate to the back, upper and lower abdomen, groin and testicles in men. Urinary symptoms such as frequency and burning can accompany stones. Initial work-up for patients suspected of having a kidney stone in the emergency room consists of a history, physical exam, blood and urine studies, and a CT scan of the abdomen and pelvis. Important information in the history includes prior stone events, systemic diseases, family history, medications, lifestyle and occupation. Whenever a stone is found that is obstructing the kidney, it's important to know whether a urinary tract infection is present. Because an obstructed kidney from a stone does not drain well, an infection can then invade the kidney and spill over into the blood causing sepsis and death. In this situation, emergent decompression of the kidney with a stent or nephrostomy tube is required. Outpatient analysis of the urine and stones can give important information on the cause of kidney stone formation. Depending on the results of these tests, certain medications can be prescribed to decrease stone formation and dissolution of the stones. General recommendations for patients with stones are to increase fluid intake to at least 8-10 glasses a day with the goal of producing 2 liters of urine a day. Fluid intake is the most important factor in reducing stone formation and progression. Dietary factors that decrease stone forming constituents include a low animal protein diet, low sodium diet, normal calcium intake and low oxalate food intake. The urologist can go into detail regarding which dietary factors are most important for you depending on your medical history and stone composition. If medical management fails to treat or dissolve the stones, surgical therapy may be indicated. Due to advancements in medical technology and optics, open surgery for stone disease is rarely required. Stones can be treated with shock-wave lithotripsy, ureteroscopy and percutaneous surgery. The least invasive form of stone surgery is shock-wave lithotripsy where under mild sedation high-energy focused pressure waves are transmitted to the stone using fluoroscopic or ultrasound guidance. This usually takes 30-60 minutes to do and has a 50-90% success rate depending on the stone size, composition and location. Some patients may need more than one treatment sessions. Complications are rare but can include bleeding, infection, and injury to adjacent organs. Another form of treatment is ureteroscopy where a lighted flexible telescope is guided into the ureter or kidney and used to either basket or fragment the stones using a laser. This does not require any incisions, usually an outpatient procedure done under anesthesia, and has an 80-100% success rate. Complications are rare and can include significant bleeding, infection and injury to the ureter or kidney. If a patient has a large stone burden or a staghorn stone, a percutaneous nephrostolithotomy may be required. This requires a small tube to be placed into the kidney from the back usually done by a radiologist. The next steps are done in the operating room where instruments can be placed through this tract to break and remove the stone using different types of energy sources including mechanical, ultrasonic or laser devices. The patient usually stays the night in the hospital and has a drainage tube in the bladder and back overnight. In summary, kidney stones can range from an asymptomatic to a life threatening problem. Kidney stones should not be ignored and life-long follow up may be needed. The best method of dealing with kidney stones is to get the proper evaluation and treatment to decrease the chances of forming new stones and decrease the risk of progression of formed stones. The urologist is best equipped to diagnose, work-up and treat this very prevalent disease. Fadi A Eliya, M.D.