What size of kidney stone requires stenting as opposed to supportive care?

From the Guidelines

Kidney stones larger than 10 mm in diameter typically require stenting rather than supportive care alone, as recommended by the American Urological Association 1. Stones between 5-10 mm fall into a gray area where the decision depends on several factors including stone location, patient symptoms, and complication risks. Stones smaller than 5 mm generally pass spontaneously with supportive care (pain management, hydration, and medical expulsive therapy such as tamsulosin 0.4 mg daily) 1. Some key points to consider in the management of kidney stones include:

• The size and location of the stone, with larger stones being more likely to require intervention 1
• The patient's symptoms, with severe pain or obstruction requiring more urgent treatment 1
• The patient's overall health, with those having a single functioning kidney or other underlying health conditions requiring more careful management 1
• The potential risks and benefits of different treatment options, including stenting, ureteroscopy, and shock wave lithotripsy 1 Stenting becomes necessary when stones cause complete obstruction, intractable pain, infection, kidney failure, or when the patient has a single functioning kidney 1. The procedure involves placing a thin tube (stent) between the kidney and bladder to relieve obstruction and facilitate stone passage or prepare for further interventions like ureteroscopy or shock wave lithotripsy. Stenting is more invasive than supportive care but prevents complications from prolonged obstruction such as kidney damage, which can occur if larger stones are left untreated 1. Patients with stents should be aware they may experience urinary frequency, urgency, and discomfort until the stent is removed following definitive stone treatment. It's also important to note that routine stenting should not be performed in patients undergoing shock wave lithotripsy, and placement of a ureteral stent prior to ureteroscopy should not be performed routinely 1.

From the Research

Kidney Stone Treatment

The size of a kidney stone that requires stenting as opposed to supportive care is not explicitly stated in the provided studies. However, the studies provide information on the treatment of kidney stones using different methods, including shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PCNL), and retrograde intrarenal surgery (RIRS).

Treatment Methods

• Shock Wave Lithotripsy (SWL): This method is used to treat renal and ureteral stones by fragmenting them into smaller pieces that can pass spontaneously down the ureter and into the bladder 2.
• Percutaneous Nephrolithotomy (PCNL): This method is used to treat renal stones and may improve stone-free rates and reduce the need for secondary interventions compared to RIRS 3.
• Retrograde Intrarenal Surgery (RIRS): This method is used to treat renal stones and may have a lower stone-free rate compared to PCNL 3.

Stone Size and Treatment

• A study found that alpha-blockers may be less effective for smaller stones (5 mm or smaller) than for larger stones (greater than 5 mm) 4.
• Another study found that PCNL may be more effective for stones larger than 2 cm 5.

Stenting

• Ureteral stenting is not mandatory after uncomplicated simple ureteroscopy and shock wave lithotripsy, but may be beneficial for patients at high risk of complications 6.
• The placement of indwelling stents can lead to stent-related morbidity, such as pain, discomfort, bladder irritability, infection, and encrustation 6.

Conclusion is not allowed, so the information will be presented in bullet points

• The provided studies do not specify a exact size of kidney stone that requires stenting as opposed to supportive care.
• The treatment of kidney stones depends on various factors, including stone size, location, and patient factors.
• Different treatment methods, such as SWL, PCNL, and RIRS, have varying success rates and potential complications.
• Alpha-blockers may be used as medical expulsive therapy to improve stone clearance, but their effectiveness may vary depending on stone size 2, 4.
• Ureteral stenting may be used to manage urinary stone disease, but its use should be carefully considered due to potential complications 6.