The main goal of initial treatment for an acute stone event is symptomatic relief with hydration and analgesia/antiemetics as needed. If signs and symptoms of infection are present, and the patient has a stone in the kidney or ureter, immediate urologic consultation should be initiated as urinary tract infection in the setting of an obstructing stone is an emergency that requires antibiotics and renal decompression to decrease the chance of life-threatening septic shock.[52]Sammon JD, Ghani KR, Karakiewicz PI, et al. Temporal trends, practice patterns, and treatment outcomes for infected upper urinary tract stones in the United States. Eur Urol. 2013 Jul;64(1):85-92.
http://www.ncbi.nlm.nih.gov/pubmed/23031677?tool=bestpractice.com
If the patient has a stone present without signs and symptoms of infection, he or she can be managed conservatively with a nonsteroidal anti-inflammatory drug (NSAID) and/or an opioid. NSAIDs have been shown to offer effective pain relief from acute kidney stone related pain with fewer side effects than opioids and acetaminophen.[53]Pathan SA, Mitra B, Cameron PA. A systematic review and meta-analysis comparing the efficacy of nonsteroidal anti-inflammatory drugs, opioids, and paracetamol in the treatment of acute renal colic. Eur Urol. 2018 Apr;73(4):583-95.
http://www.ncbi.nlm.nih.gov/pubmed/29174580?tool=bestpractice.com
If the pain cannot be managed with conservative therapy, then renal decompression or definitive stone treatment should be considered.[1]Khan SR, Pearle MS, Robertson WG, et al. Kidney stones. Nat Rev Dis Primers. 2016 Feb 25;2:16008.
https://www.doi.org/10.1038/nrdp.2016.8
http://www.ncbi.nlm.nih.gov/pubmed/27188687?tool=bestpractice.com
There is evidence to support that medical expulsive therapy (MET), namely alpha-blockers, may increase ureteral stone passage rate and decrease the time to stone passage, particularly in distal ureteral stones <10 mm in size.[54]Eisner BH, Goldfarb DS, Pareek G. Pharmacologic treatment of kidney stone disease. Urol Clin North Am. 2013 Feb;40(1):21-30.
http://www.ncbi.nlm.nih.gov/pubmed/23177632?tool=bestpractice.com
[
]
What are the effects of alpha‐blockers as medical expulsive therapy for people with ureteral stones?/cca.html?targetUrl=https://www.cochranelibrary.com/cca/doi/10.1002/cca.2153/fullShow me the answer However, if a 4- to 6-week trial of MET has been attempted without successful stone passage, the patient should undergo definitive surgical management.
For patients at risk for, or with a history of recurrent stones, secondary preventive measures should be tailored toward underlying metabolic factors that promote stone formation. For all such patients, dietary modification with adequate hydration is an essential aspect of ongoing management.
Urgent consideration: obstruction and infection
Patients with urinary calculi along with fever and other signs or symptoms of infection need emergency urologic consultation for drainage and intravenous antibiotics. Failure to perform rapid renal decompression can perpetuate urosepsis and result in death. Drainage can be accomplished in two ways. A urologist can place a ureteric stent past the obstruction and achieve drainage. Alternatively, a percutaneous nephrostomy tube can be placed by interventional radiology.
Management of stones <10 mm and no complications
Acute medical treatment for renal or ureteric colic includes conservative therapy, such as hydration, analgesia (an NSAID and/or an opioid), and an anti-emetic.[53]Pathan SA, Mitra B, Cameron PA. A systematic review and meta-analysis comparing the efficacy of nonsteroidal anti-inflammatory drugs, opioids, and paracetamol in the treatment of acute renal colic. Eur Urol. 2018 Apr;73(4):583-95.
http://www.ncbi.nlm.nih.gov/pubmed/29174580?tool=bestpractice.com
[55]Afshar K, Jafari S, Marks AJ, et al. Nonsteroidal anti-inflammatory drugs (NSAIDs) and non-opioids for acute renal colic. Cochrane Database Syst Rev. 2015 Jun 29;(6):CD006027.
https://www.doi.org/10.1002/14651858.CD006027.pub2
http://www.ncbi.nlm.nih.gov/pubmed/26120804?tool=bestpractice.com
[
]
Is there randomized controlled trial evidence to support the use of nonsteroidal anti-inflammatory drugs (NSAIDS) compare with other analgesics and each other in people with acute renal colic?/cca.html?targetUrl=https://cochranelibrary.com/cca/doi/10.1002/cca.920/fullShow me the answer NSAIDs should be offered first-line unless contraindicated (e.g., patients at risk of renal impairment, cardiac failure, gastric ulceration).[38]Türk C, Neisius A, Petrik A, et al. European Association of Urology. Urolithiasis. 2020 [internet publication].
https://uroweb.org/guideline/urolithiasis/
[56]National Institute for Health and Care Excellence. Renal and ureteric stones: assessment and management. January 2019 [internet publication].
https://www.nice.org.uk/guidance/ng118/
[57]Davenport K, Waine E. The role of non-steroidal anti-inflammatory drugs in renal colic. Pharmaceuticals (Basel). 2010 Apr 28;3(5):1304-10.
https://www.doi.org/10.3390/ph3051304
http://www.ncbi.nlm.nih.gov/pubmed/27713303?tool=bestpractice.com
[Evidence C]596d5fd1-3089-4b28-b82e-fded1ebf4043guidelineCWhat is the clinical effectiveness of nonsteroidal anti-inflammatory drugs (NSAIDs) in managing acute pain in people with symptomatic renal or ureteric stones?[56]National Institute for Health and Care Excellence. Renal and ureteric stones: assessment and management. January 2019 [internet publication].
https://www.nice.org.uk/guidance/ng118/
Parental NSAIDs provide the most sustained pain relief, with fewer adverse effects, when compared with opioids.[53]Pathan SA, Mitra B, Cameron PA. A systematic review and meta-analysis comparing the efficacy of nonsteroidal anti-inflammatory drugs, opioids, and paracetamol in the treatment of acute renal colic. Eur Urol. 2018 Apr;73(4):583-95.
http://www.ncbi.nlm.nih.gov/pubmed/29174580?tool=bestpractice.com
[58]Gu HY, Luo J, Wu JY, et al. Increasing nonsteroidal anti-inflammatory drugs and reducing opioids or paracetamol in the management of acute renal colic: based on three-stage study design of network meta-analysis of randomized controlled trials. Front Pharmacol. 2019;10:96.
https://www.doi.org/10.3389/fphar.2019.00096
http://www.ncbi.nlm.nih.gov/pubmed/30853910?tool=bestpractice.com
However, NSAIDs can be offered by any route.[56]National Institute for Health and Care Excellence. Renal and ureteric stones: assessment and management. January 2019 [internet publication].
https://www.nice.org.uk/guidance/ng118/
[Evidence C]596d5fd1-3089-4b28-b82e-fded1ebf4043guidelineCWhat is the clinical effectiveness of nonsteroidal anti-inflammatory drugs (NSAIDs) in managing acute pain in people with symptomatic renal or ureteric stones?[56]National Institute for Health and Care Excellence. Renal and ureteric stones: assessment and management. January 2019 [internet publication].
https://www.nice.org.uk/guidance/ng118/
Patients with newly diagnosed ureteric stones <10 mm without complicating factors (urosepsis, intractable pain and/or vomiting, impending acute renal failure, obstruction of a solitary or transplanted kidney, or bilateral obstruction) can be managed expectantly.[48]Assimos D, Krambeck A, Miller NL, et al. Surgical management of stones: American Urological Association/Endourological Society Guideline. 2016 [internet publication].
http://www.auanet.org/education/guidelines/surgical-management-of-stones.cfm
Many ureteric stones <10 mm pass spontaneously, with exact passage rate related to both stone size and location.[59]Jendeberg J, Geijer H, Alshamari M, et al. Size matters: the width and location of a ureteral stone accurately predict the chance of spontaneous passage. Eur Radiol. 2017 Nov;27(11):4775-85.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5635101/
http://www.ncbi.nlm.nih.gov/pubmed/28593428?tool=bestpractice.com
MET using an alpha-blocker such as tamsulosin, alfuzosin, or silodosin may be of benefit in promoting larger (but still <10 mm) distal ureteral stone passage; however, efficacy rates have been questioned.[60]Campschroer T, Zhu X, Vernooij RW, et al. Alpha-blockers as medical expulsive therapy for ureteral stones. Cochrane Database Syst Rev. 2018;(4):CD008509.
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD008509.pub3/full
http://www.ncbi.nlm.nih.gov/pubmed/29620795?tool=bestpractice.com
[61]Sridharan K, Sivaramakrishnan G. Efficacy and safety of alpha blockers in medical expulsive therapy for ureteral stones: a mixed treatment network meta-analysis and trial sequential analysis of randomized controlled clinical trials. Expert Rev Clin Pharmacol. 2018 Mar;11(3):291-307.
http://www.ncbi.nlm.nih.gov/pubmed/29334287?tool=bestpractice.com
[62]Meltzer AC, Burrows PK, Wolfson AB, et al. Effect of tamsulosin on passage of symptomatic ureteral stones: a randomized clinical trial. JAMA Intern Med. 2018 Aug 1;178(8):1051-7.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6082698/
http://www.ncbi.nlm.nih.gov/pubmed/29913020?tool=bestpractice.com
[63]Hollingsworth JM, Canales BK, Rogers MA, et al. Alpha blockers for treatment of ureteric stones: systematic review and meta-analysis. BMJ. 2016 Dec 1;355:i6112.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5131734/
http://www.ncbi.nlm.nih.gov/pubmed/27908918?tool=bestpractice.com
[64]Wang RC, Smith-Bindman R, Whitaker E, et al. Effect of tamsulosin on stone passage for ureteral stones: a systematic review and meta-analysis. Ann Emerg Med. 2017 Mar;69(3):353-61.e3.
http://www.ncbi.nlm.nih.gov/pubmed/27616037?tool=bestpractice.com
[65]Aboumarzouk OM, Jones P, Amer T, et al. What is the role of alpha-blockers for medical expulsive therapy? Results rrom a meta-analysis of 60 randomized trials and over 9500 patients. Urology. 2018 Sep;119:5-16.
https://www.doi.org/10.1016/j.urology.2018.03.028
http://www.ncbi.nlm.nih.gov/pubmed/29626570?tool=bestpractice.com
[66]Hsu YP, Hsu CW, Bai CH, et al. Silodosin versus tamsulosin for medical expulsive treatment of ureteral stones: aA systematic review and meta-analysis. PLoS One. 2018;13(8):e0203035.
https://www.doi.org/10.1371/journal.pone.0203035
http://www.ncbi.nlm.nih.gov/pubmed/30153301?tool=bestpractice.com
[
]
What are the effects of alpha‐blockers as medical expulsive therapy for people with ureteral stones?/cca.html?targetUrl=https://www.cochranelibrary.com/cca/doi/10.1002/cca.2153/fullShow me the answer These agents can cause ureteric relaxation of smooth muscle and antispasmodic activity of the ureter leading to stone passage.[67]Micali S, Grande M, Sighinolfi MC, et al. Medical therapy of urolithiasis. J Endourol. 2006 Nov;20(11):841-7.
http://www.ncbi.nlm.nih.gov/pubmed/17144848?tool=bestpractice.com
Patients should be made aware that prescribing alpha-blockers for this indication is considered an off-label use of these drugs. Additionally, tamsulosin has been associated with intraoperative floppy iris syndrome, therefore it should not be prescribed if a patient has planned cataract surgery.
If there is spontaneous passage of stones, most pass within 4 to 6 weeks. Surgical intervention is indicated in the presence of persistent obstruction, failure of stone progression, sepsis, or persistent or increasing colic. Such patients in general are followed up with periodic imaging, with either a KUB and renal ultrasound or a noncontrast computed tomography (CT) abdomen and pelvis to monitor stone position and degree of hydronephrosis.
Management of stones ≥10 mm or smaller stones that fail to pass with MET
Management can be affected by stone size, location, and composition, in addition to anatomic and clinical features. For larger stones (≥10 mm), and for smaller stones that remain despite conservative therapies, additional surgical treatment is necessary. Historically, open surgery was the only way to remove stones. However, with the development and success of endourology, a term used to describe less invasive surgical techniques that involve closed manipulation of the urinary tract with scopes, open surgery is now rarely performed.
Calculi between 10-20 mm are in general treated with extracorporeal shock wave lithotripsy (ESWL) or ureteroscopy as first-line therapy. However for ESWL, the stone-free rates for lower pole stones are inferior (25%) compared with nonlower pole stones (40%).[68]Geraghty R, Burr J, Simmonds N, et al. Shock wave lithotripsy outcomes for lower pole and non-lower pole stones from a university teaching hospital: parallel group comparison during the same time period. Urol Ann. 2015 Jan-Mar;7(1):46-8.
https://www.doi.org/10.4103/0974-7796.148601
http://www.ncbi.nlm.nih.gov/pubmed/25657543?tool=bestpractice.com
Percutaneous nephrostolithotomy (PCNL) for calculi between 10-20 mm achieves better stone-free rates for lower pole stones than ESWL.[69]Junbo L, Yugen L, Guo J, et al. Retrograde intrarenal surgery vs. percutaneous nephrolithotomy vs. extracorporeal shock wave lithotripsy for lower pole renal stones 10-20 mm : a meta-analysis and systematic review. Urol J. 2019 May 5;16(2):97-106.
https://www.doi.org/10.22037/uj.v0i0.4681
http://www.ncbi.nlm.nih.gov/pubmed/30604405?tool=bestpractice.com
Similarly, cystine stones >15-20 mm and brushite stones respond poorly to ESWL.[70]Kachel TA, Vijan SR, Dretler SP. Endourological experience with cystine calculi and a treatment algorithm. J Urol. 1991 Jan;145(1):25-8.
http://www.ncbi.nlm.nih.gov/pubmed/1984093?tool=bestpractice.com
Hence, patients with features predictive of poor outcome, obesity, or a body build not conducive to ESWL, may be advised alternatives such as PCNL or ureteroscopy, which show superior results.[71]Grasso M, Ficazzola M. Retrograde ureteropyeloscopy for lower pole caliceal calculi. J Urol. 1999 Dec;162(6):1904-8.
http://www.ncbi.nlm.nih.gov/pubmed/10569534?tool=bestpractice.com
Patients with stones >20 mm should primarily be treated with PCNL unless specific indications for an alternate procedure are present. While PCNL is the first-line therapy for large stones, ureteroscopy has been reported to achieve a mean stone-free rate as high as 93.7% (77.0% to 96.7%) for stones >20 mm in size (mean 25 mm) with acceptable overall complication rates (10.1%). However, this requires an average of 1.6 procedures per patient.[72]Aboumarzouk OM, Monga M, Kata SG, et al. Flexible ureteroscopy and laser lithotripsy for stones >2 cm: a systematic review and meta-analysis. J Endourol. 2012 Oct;26(10):1257-63.
http://www.ncbi.nlm.nih.gov/pubmed/22642568?tool=bestpractice.com
[73]Kang SK, Cho KS, Kang DH, et al. Systematic review and meta-analysis to compare success rates of retrograde intrarenal surgery versus percutaneous nephrolithotomy for renal stones >2 cm: an update. Medicine (Baltimore). 2017 Dec;96(49):e9119.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5728962/
http://www.ncbi.nlm.nih.gov/pubmed/29245347?tool=bestpractice.com
For solitary renal calculi <10 mm, ESWL and ureteroscopy are both valid options. Ureteroscopy or PCNL can be utilized when ESWL fails, or in the presence of anatomic abnormalities or other special circumstances.[74]Lingeman JE, Matlaga BR, Evan AP. Surgical management of upper urinary tract calculi. In: Wein AJ, Kavoussi LR, Novick AC, et al., eds. Campbell's urology. 9th ed. Philadelphia, PA: Saunders Elsevier; 2007:1431-1507. A ureteral stent, an internal tube extending from the kidney to the bladder, is often left temporarily in place after ureteroscopy to promote collecting system drainage while any edema from the stone or the procedure resolves. Stents are recommended in cases of functionally or anatomically solitary kidneys, ureteral stricture, noted ureteral injury, or cases with a planned second stage procedure. While stents can be omitted in cases of uncomplicated ureteroscopy, randomized multicenter trials are warranted to better determine which patients can safely undergo ureteroscopy without ureteral stent placement.[75]Ordonez M, Hwang EC, Borofsky M, et al. Ureteral stent versus no ureteral stent for ureteroscopy in the management of renal and ureteral calculi. Cochrane Database Syst Rev. 2019 Feb 6;2:CD012703.
https://www.doi.org/10.1002/14651858.CD012703.pub2
http://www.ncbi.nlm.nih.gov/pubmed/30726554?tool=bestpractice.com
Extracorporeal shock wave lithotripsy (ESWL) is the least invasive method of definitive stone treatment and is suitable for most patients with uncomplicated stone disease. In ESWL, shock waves are generated by a source external to the patient's body and are then propagated into the body and focused on a renal stone. The shock waves break stones by both compressive and tensile forces. The stone fragments then pass out in the urine. Limitations to ESWL include stone size and location. ESWL has the potential benefit of being done under intravenous sedation/analgesia, without need for general anesthesia. Treatment with tamsulosin appears to be effective in assisting stone clearance in patients with renal and ureteric calculi.[76]Zhu Y, Duijvesz D, Rovers MM, et al. Alpha-blockers to assist stone clearance after extracorporeal shock wave lithotripsy: a meta-analysis. BJU Int. 2010 Jul;106(2):256-61.
http://www.ncbi.nlm.nih.gov/pubmed/19889063?tool=bestpractice.com
While ESWL has been shown to have limited success with lower pole stones there is evidence to suggest that ancillary maneuvers such as percussion, diuresis, and inversion increase stone-free rates.[77]Liu LR, Li QJ, Wei Q, et al. Percussion, diuresis, and inversion therapy for the passage of lower pole kidney stones following shock wave lithotripsy. Cochrane Database Syst Rev. 2013;(12):CD008569.
http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD008569.pub2/full
http://www.ncbi.nlm.nih.gov/pubmed/24318643?tool=bestpractice.com
Contraindications to ESWL treatment include pregnancy, severe skeletal malformations, severe obesity, aortic and/or renal artery aneurysms, uncontrolled hypertension, disorders of blood coagulation, and uncontrolled urinary tract infections.[78]Loughlin KR. Management of urologic problems during pregnancy. Urology. 1994 Aug;44(2):159-69.
http://www.ncbi.nlm.nih.gov/pubmed/8048189?tool=bestpractice.com
[79]Ignatoff JM, Nelson JB. Use of extracorporeal shock wave lithotripsy in a solitary kidney with renal artery aneurysm. J Urol. 1993 Feb;149(2):359-60.
http://www.ncbi.nlm.nih.gov/pubmed/8426419?tool=bestpractice.com
Ureteroscopy involves placing a small semi-rigid or flexible scope per urethra and into the ureter and/or kidney. Once the stone is visualized, it can be fragmented using a laser and/or grasped with a basket and removed. The procedure is more invasive than ESWL, but is generally thought to have a higher stone-free rate. General anesthesia is routinely used, and a ureteric stent may be placed at the end of the procedure.[80]Wang H, Man L, Li G, et al. Meta-analysis of stenting versus non-stenting for the treatment of ureteral stones. PLoS One. 2017 Jan 9;12(1):e0167670.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5221881/
http://www.ncbi.nlm.nih.gov/pubmed/28068364?tool=bestpractice.com
[
]
For adults undergoing ureteroscopy for ureteral calculi clearance, how does placement of a ureteral stent affect outcomes?/cca.html?targetUrl=https://www.cochranelibrary.com/cca/doi/10.1002/cca.2494/fullShow me the answer The procedure can be safely performed in coagulopathic patients using a holmium laser. Single-use flexible ureteropyeloscopy (FURS) demonstrates comparable efficacy with reusable FURS in treating renal calculi.[81]Davis NF, Quinlan MR, Browne C, et al. Single-use flexible ureteropyeloscopy: a systematic review. World J Urol. 2018 Apr;36(4):529-36.
https://www.doi.org/10.1007/s00345-017-2131-4
http://www.ncbi.nlm.nih.gov/pubmed/29177820?tool=bestpractice.com
For patients requiring stone removal, both ESWL and ureteroscopy are considered acceptable first-line surgical treatments for stones in the ureter.[48]Assimos D, Krambeck A, Miller NL, et al. Surgical management of stones: American Urological Association/Endourological Society Guideline. 2016 [internet publication].
http://www.auanet.org/education/guidelines/surgical-management-of-stones.cfm
[38]Türk C, Neisius A, Petrik A, et al. European Association of Urology. Urolithiasis. 2020 [internet publication].
https://uroweb.org/guideline/urolithiasis/
Ureteroscopic stone-free rates are better than ESWL rates for distal ureteric stones regardless of size and for proximal ureteric stones >10 mm.[82]Dell'Atti L, Papa S. Ten-year experience in the management of distal ureteral stones greater than 10 mm in size. G Chir. 2016 Jan-Feb;37(1):27-30.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4859772/
http://www.ncbi.nlm.nih.gov/pubmed/27142822?tool=bestpractice.com
[83]Cui X, Ji F, Yan H, et al. Comparison between extracorporeal shock wave lithotripsy and ureteroscopic lithotripsy for treating large proximal ureteral stones: a meta-analysis. Urology. 2015 Apr;85(4):748-56.
http://www.ncbi.nlm.nih.gov/pubmed/25681251?tool=bestpractice.com
However, ureteroscopic removal has a higher complication rate and longer hospital stay.[84]Drake T, Grivas N, Dabestani S, et al. What are the benefits and harms of ureteroscopy compared with shock-wave lithotripsy in the treatment of upper ureteral stones? A systematic review. Eur Urol. 2017 Nov;72(5):772-86.
http://www.ncbi.nlm.nih.gov/pubmed/28456350?tool=bestpractice.com
[85]Aboumarzouk OM, Kata SG, Keeley FX, et al. Extracorporeal shock wave lithotripsy (ESWL) versus ureteroscopic management for ureteric calculi. Cochrane Database Syst Rev. 2012;(5):CD006029.
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD006029.pub4/full
http://www.ncbi.nlm.nih.gov/pubmed/22592707?tool=bestpractice.com
Percutaneous antegrade ureteroscopy involves percutaneous antegrade removal of ureteric stones, and can be considered in select cases with very large (>15 mm) stones impacted in the upper ureter or when retrograde access is not possible.[86]Maheshwari PN, Oswal AT, Andankar M, et al. Is antegrade ureteroscopy better than retrograde ureteroscopy for impacted large upper ureteral calculi? J Endourol. 1999 Jul-Aug;13(6):441-4.
http://www.ncbi.nlm.nih.gov/pubmed/10479011?tool=bestpractice.com
[87]el-Nahas AR, Eraky I, el-Assmy AM, et al. Percutaneous treatment of large upper tract stones after urinary diversion. Urology. 2006 Sep;68(3):500-4.
http://www.ncbi.nlm.nih.gov/pubmed/16979745?tool=bestpractice.com
[88]Wang Q, Guo J, Hu H, et al. Rigid ureteroscopic lithotripsy versus percutaneous nephrolithotomy for large proximal ureteral stones: a meta-analysis. PLoS One. 2017 Feb 9;12(2):e0171478.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5300230/
http://www.ncbi.nlm.nih.gov/pubmed/28182718?tool=bestpractice.com
Percutaneous nephrostolithotomy (PCNL) is a minimally invasive form of treatment that is usually reserved for renal and proximal ureteric stones (i.e., in the lower pole) and those that are large (>20 mm), have failed therapy with ESWL and ureteroscopy, or are associated with complex renal anatomy.[48]Assimos D, Krambeck A, Miller NL, et al. Surgical management of stones: American Urological Association/Endourological Society Guideline. 2016 [internet publication].
http://www.auanet.org/education/guidelines/surgical-management-of-stones.cfm
Percutaneous access into the kidney is gained from the flank. Current evidence indicates that both fluoroscopy and ultrasound (US) guidance may be successfully used for obtaining percutaneous renal access. Combining US and fluoroscopy seems to improve the outcome both with regard to success in achieving access and reducing complications.[89]Breda A, Territo A, Scoffone C, et al. The evaluation of radiologic methods for access guidance in percutaneous nephrolithotomy: a systematic review of the literature. Scand J Urol. 2018 Apr;52(2):81-6.
https://www.doi.org/10.1080/21681805.2017.1394910
http://www.ncbi.nlm.nih.gov/pubmed/29130789?tool=bestpractice.com
Once access is gained, a large sheath is placed into the kidney and a nephroscope is used to help remove the stone. For large stones, ultrasound lithotripsy is usually used to break and remove the stone. PCNL usually requires a hospital stay and has more potential complications than either ESWL or ureteroscopy. In stones of 20-30 mm, ESWL is associated with poor stone-free rates (34%) compared to those achieved with PCNL (90%). ESWL is further associated with an increased number of procedures and need for ancillary treatments as the stone size increases.[90]Lingeman JE, Coury TA, Newman DM, et al. Comparison of results and morbidity of percutaneous nephrostolithotomy and extracorporeal shock wave lithotripsy. J Urol. 1987 Sep;138(3):485-90.
http://www.ncbi.nlm.nih.gov/pubmed/3625845?tool=bestpractice.com
Laparoscopic stone removal is another minimally invasive method to remove ureteric or renal stones. However, it is still more invasive, requires a longer hospital stay, and has a much higher learning curve than ureteroscopy or ESWL. With the advances in ESWL and endourologic surgery (i.e., ureteroscopy and PCNL) during the past 20 years, the indications for open stone surgery have markedly diminished. Laparoscopic or open surgical stone removal may still be indicated in rare cases where ESWL, ureteroscopy, and percutaneous ureteroscopy fail or are unlikely to be successful; anatomic deformities preclude a minimally invasive approach; the patient requires concomitant open surgery, pyeloplasty, or a partial nephrectomy; or in patients with a large stone burden requiring a single clearance procedure.[48]Assimos D, Krambeck A, Miller NL, et al. Surgical management of stones: American Urological Association/Endourological Society Guideline. 2016 [internet publication].
http://www.auanet.org/education/guidelines/surgical-management-of-stones.cfm
[38]Türk C, Neisius A, Petrik A, et al. European Association of Urology. Urolithiasis. 2020 [internet publication].
https://uroweb.org/guideline/urolithiasis/
Stones during pregnancy
A symptomatic stone occurs in 1 out of every 200 to 1500 pregnancies with 80% to 90% of these occurring in the second or third trimester.[91]Semins MJ, Matlaga BR. Kidney stones during pregnancy. Nat Rev Urol. 2014 Mar;11(3):163-8.
http://www.ncbi.nlm.nih.gov/pubmed/24515090?tool=bestpractice.com
It has been reported that 48% to 80% of stones pass spontaneously during pregnancy.[31]Fulgham PF, Assimos DG, Pearle MS, et al. Clinical effectiveness protocols for imaging in the management of ureteral calculous disease: AUA Technology Assessment. J Urol. 2013 Apr;189(4):1203-13.
http://www.jurology.com/article/S0022-5347%2812%2905259-7/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/23085059?tool=bestpractice.com
[92]Burgess KL, Gettman MT, Rangel LJ, et al. Diagnosis of urolithiasis and rate of spontaneous passage during pregnancy. J Urol. 2011 Dec;186(6):2280-4.
http://www.ncbi.nlm.nih.gov/pubmed/22014825?tool=bestpractice.com
Pregnant women with renal colic that is not controlled with oral analgesia or with an obstructing stone and signs of infection (fever or urinalysis/urine culture showing a possible urine infection) should receive a ureteric stent or percutaneous nephrostomy tube. Of note, these tubes should be changed more often (every 6 to 8 weeks) due to concern for rapid encrustation as a result of the metabolic changes seen with pregnancy. If the patient has no evidence of infection, definitive therapy with ureteroscopy may be performed and has been demonstrated to be safe.[93]Semins MJ, Trock BJ, Matlaga BR. The safety of ureteroscopy during pregnancy: a systematic review and meta-analysis. J Urol. 2009 Jan;181(1):139-43.
http://www.ncbi.nlm.nih.gov/pubmed/19012926?tool=bestpractice.com
ESWL and PCNL are contraindicated in pregnancy.
Ongoing medical therapy and dietary modification
Oral alkalinization therapy with medications such as potassium citrate and sodium bicarbonate may be beneficial in dissolving uric acid stones and preventing uric acid supersaturation. It may be used for treating uric acid stones that do not require urgent surgical treatment, as well as asymptomatic stones. The ideal goal for alkalinization therapy for uric acid stones is to maintain the urine pH between 6.5 and 7.0. Potassium citrate is the first-line therapy. In patients with CHF or renal failure, extra care should be taken when prescribing alkalinization therapy. Alkalinization therapy also plays an important role in preventing calcium and cystine stones.
Long-term dietary modification is essential for preventing future calculi. This modification is centered on increasing fluid intake. At least 2 liters of urine output daily should be recommended to help prevent future episodes of stone formation.[94]Cheungpasitporn W, Rossetti S, Friend K, et al. Treatment effect, adherence, and safety of high fluid intake for the prevention of incident and recurrent kidney stones: a systematic review and meta-analysis. J Nephrol. 2016 Apr;29(2):211-9.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4831051/
http://www.ncbi.nlm.nih.gov/pubmed/26022722?tool=bestpractice.com
Decreased dietary sodium, protein, and oxalate should be recommended for stone prevention. Increased citrus fruit intake is recommended to prevent stone recurrence.[95]Pak CY. Kidney stones. Lancet. 1998 Jun 13;351(9118):1797-801.
http://www.ncbi.nlm.nih.gov/pubmed/9635968?tool=bestpractice.com
Normal calcium intake (i.e., 1000 mg/day to 1200 mg/day) is recommended.[95]Pak CY. Kidney stones. Lancet. 1998 Jun 13;351(9118):1797-801.
http://www.ncbi.nlm.nih.gov/pubmed/9635968?tool=bestpractice.com
Dietary calcium restriction can lead to less binding of calcium to oxalate in the GI tract, promoting hyperoxaluria and potentiating the risk for stone formation; furthermore, it could have detrimental effects on bone health.
Where specific metabolic abnormalities exist and are not responsive to dietary modification, specific preventive therapies may be required.[51]Pearle MS, Goldfarb DS, Assimos DG, et al.; American Urological Association. Medical management of kidney stones: AUA guideline. J Urol. 2014 Aug;192(2):316-24.
http://www.jurology.com/article/S0022-5347(14)03532-0/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/24857648?tool=bestpractice.com
[96]Gambaro G, Croppi E, Coe F, et al; Consensus Conference Group. Metabolic diagnosis and medical prevention of calcium nephrolithiasis and its systemic manifestations: a consensus statement. J Nephrol. 2016 Dec;29(6):715-34.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5080344/
http://www.ncbi.nlm.nih.gov/pubmed/27456839?tool=bestpractice.com
These include:
Uric acid stones: urinary alkalinization with potassium citrate or sodium bicarbonate
Hyperuricosuria, recurrent calcium oxalate stones, and normal urine calcium: allopurinol or febuxostat
Febuxostat should only be prescribed for patients who can not tolerate allopurinol or where treatment with allopurinol has failed, and who have been counselled regarding cardiovascular risk[97]US Food and Drug Administration. FDA adds Boxed Warning for increased risk of death with gout medicine Uloric (febuxostat). 21 February 2019 [internet publication].
https://www.fda.gov/Drugs/DrugSafety/ucm631182.htm
The double-blind Cardiovascular Safety of Febuxostat or Allopurinol in Patients with Gout (CARES) safety trial found that cardiovascular death and all cause mortality were significantly more common among patients taking febuxostat than allopurinol (4.3% vs. 3.2%, HR 1.34 [95% CI 1.03 to 1.73]; 7.8% vs. 6.4%, HR 1.22 [95% CI 1.01 to 1.47], respectively).[98]White WB, Saag KG, Becker MA, et al. Cardiovascular safety of febuxostat or allopurinol in patients with gout. N Engl J Med. 2018 Mar 12;378(13):1200-10.
https://www.doi.org/10.1056/NEJMoa1710895
http://www.ncbi.nlm.nih.gov/pubmed/29527974?tool=bestpractice.com
Treatment group did not differ with respect to a primary composite outcome of cardiovascular events.
Febuxostat should be avoided in patients with pre-existing major cardiovascular disease (e.g., myocardial infarction, unstable angina, stroke), unless no other therapy options are appropriate.[99]Medicines and Healthcare products Regulatory Agency. Febuxostat (Adenuric): increased risk of cardiovascular death and all-cause mortality in clinical trial in patients with a history of major cardiovascular disease. July 2019 [internet publication].
https://www.gov.uk/drug-safety-update/febuxostat-adenuric-increased-risk-of-cardiovascular-death-and-all-cause-mortality-in-clinical-trial-in-patients-with-a-history-of-major-cardiovascular-disease
Hypercalciuria and recurrent calcium stones: thiazide diuretic with or without potassium supplementation (potassium citrate or potassium chloride)
Hypocitraturia and recurrent calcium stones: urinary alkalinization (e.g., potassium citrate; sodium bicarbonate or sodium citrate can be considered if the patient is at risk for hyperkalemia)[100]Phillips R, Hanchanale VS, Myatt A, et al. Citrate salts for preventing and treating calcium containing kidney stones in adults. Cochrane Database Syst Rev. 2015;(10):CD010057.
http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD010057.pub2/full
http://www.ncbi.nlm.nih.gov/pubmed/26439475?tool=bestpractice.com
Hyperoxaluria: oxalate chelator (e.g., calcium, magnesium, or cholestyramine), potassium citrate, pyridoxine
Cystinuria: urinary alkalinization with potassium citrate, thiol binding agent (e.g., tiopronin which is tolerated better than d-penicillamine)
Struvite stones: urease inhibitor (e.g., acetohydroxamic acid), which is best reserved for complex/recurrent struvite stones in which surgical management has been exhausted.[14]Jung H, Andonian S, Assimos D, et al. Urolithiasis: evaluation, dietary factors, and medical management: an update of the 2014 SIU-ICUD international consultation on stone disease. World J Urol. 2017 Sep;35(9):1331-40.
https://www.doi.org/10.1007/s00345-017-2000-1
http://www.ncbi.nlm.nih.gov/pubmed/28160089?tool=bestpractice.com
Secondary care supervision should be employed as it can produce severe adverse effects such as phlebitis and hypercoagulability.
Most of these strategies are applied to children with nephrolithiasis, although there is a limited number of well-designed trials in this age group.[101]Kern A, Grimsby G, Mayo H, et al. Medical and dietary interventions for preventing recurrent urinary stones in children. Cochrane Database Syst Rev. 2017;(11):CD011252.
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD011252.pub2/full
http://www.ncbi.nlm.nih.gov/pubmed/29117629?tool=bestpractice.com
[102]Barreto L, Jung JH, Abdelrahim A, et al. Medical and surgical interventions for the treatment of urinary stones in children. Cochrane Database Syst Rev. 2019 Oct 9;10:CD010784.
https://www.doi.org/10.1002/14651858.CD010784.pub3
http://www.ncbi.nlm.nih.gov/pubmed/31596944?tool=bestpractice.com