From the Guidelines
Urolithiasis, also known as kidney stones, is a condition where small, hard mineral deposits form inside the kidneys. Causes and Risk Factors: The main cause of urolithiasis is the concentration of certain substances in the urine, such as calcium, oxalate, and uric acid, as stated in the study by 1. Risk factors include family history, dehydration, obesity, diet high in animal protein, sodium, and sugar, and certain medical conditions like gout, inflammatory bowel disease, and renal tubular acidosis. Preventive Measures: To prevent urolithiasis, it is recommended to drink at least 2 L of water per day to achieve at least 2 L of urine per day, as suggested by 1 and 1. Limiting animal protein, sodium, and sugar intake, and maintaining a healthy weight is also recommended. A diet low in oxalate (limit foods like spinach, beets, and rhubarb) and moderate in calcium (1000-1200 mg per day) is also recommended. Signs and Symptoms: The symptoms of urolithiasis include severe pain in the side or back, below the ribs, pain that radiates to the lower abdomen or groin, frequent or painful urination, nausea and vomiting, and blood in the urine, as mentioned in the study by 1. Treatment: The treatment of urolithiasis depends on the size and location of the stone. Small stones (less than 5 mm) can be treated with pain medication like acetaminophen (650-1000 mg every 4-6 hours) or ibuprofen (400-800 mg every 4-6 hours) and increased fluid intake. Medium-sized stones (5-10 mm) may require medical expulsive therapy with alpha-blockers like tamsulosin (0.4 mg daily) or nifedipine (30-60 mg daily) for 1-2 months. Large stones (greater than 10 mm) may require surgical intervention like extracorporeal shock wave lithotripsy (ESWL) or percutaneous nephrolithotomy (PCNL), as stated in the study by 1. In some cases, ureteroscopy with laser lithotripsy may be performed. Some key points to consider in the treatment of urolithiasis include:
- The use of pharmacologic monotherapy with a thiazide diuretic, citrate, or allopurinol to prevent recurrent nephrolithiasis in patients with active disease, as recommended by 1 and 1.
- The importance of stone analysis to determine the composition of the stone and guide treatment, as mentioned in the study by 1.
- The use of flexible ureteroscopy (FURS) as a treatment option for upper tract stones, as discussed in the study by 1.
- The recommendation to follow the treatment algorithms for urolithiasis as outlined in the EAU guidelines, as stated in the study by 1.
From the Research
Causes and Risk Factors
- Urolithiasis is a heterogeneous disorder with varying chemical composition and pathophysiologic background 2
- Stones develop from a wide variety of metabolic or environmental disturbances, including hypercalciuria, hypocitraturia, undue urinary acidity, hyperuricosuria, hyperoxaluria, infection with urease-producing organisms, and cystinuria 2
- Risk factors for urolithiasis include general factors such as young age at manifestation, familial disposition, genetic or acquired diseases with risk of stone formation, and drugs 3
- The prevalence and incidence of kidney stones has continuously increased over the last years, with a substantial morbidity including chronic kidney disease and end stage kidney disease as well as significantly increased risk for cardiovascular diseases 3
Preventive Measures
- Dietary changes can help prevent stone recurrence, and patients who are discharged should be advised on these changes 4
- Various therapies, including thiazide diuretics and alkaline citrate, are used in an attempt to prevent stones recurrence induced by hypercalciuria and hyperoxaluria, but the scientific evidence for their effectiveness is less convincing 5
- Effective medical treatments, capable of correcting underlying derangements, have been formulated, including sodium cellulose phosphate, thiazide, and orthophosphate for hypercalciuric nephrolithiasis; potassium citrate for hypocitraturic calcium nephrolithiasis; acetohydroxamic acid for infection stones; and D-penicillamine and alpha-mercaptopropionylglycine for cystinuria 2
Signs and Symptoms
- Urolithiasis commonly presents with flank pain, hematuria, and nausea/vomiting 4
- History, examination, and assessment with several laboratory tests are cornerstones of evaluation, and urinalysis is not diagnostic, but it may be used in association with other assessments 4
Treatment Options
- The medical management of urolithiasis is done by medical treatments and/or by surgical intervention for the stones extraction by the techniques such as extracorporeal shock wave lithotripsy (ESWL), ureteroscopy (URS), percutaneous nephrolithotomy (PCNL) and open surgery 5
- Nonsteroidal anti-inflammatory drugs remain first-line therapy, with opioids or intravenous lidocaine reserved for refractory pain, and tamsulosin can increase passage in larger stones but has not demonstrated benefit in smaller stones 4
- Surgical intervention is based upon stone size, duration, and modifying factors, and flexible ureteroscopy can be a useful tool in stones less than 2 cm in size with the availability of smaller flexible ureteroscopes and access sheaths 6
- Laparoscopic assisted percutaneous nephrolithotomy has shown good clearance rates with minimal morbidity and less likelihood of ancillary procedures, and ultrasound guided percutaneous approaches for ectopic kidneys should be performed by surgeons well versed with it 6